RSGB Tonight @ 8 - How Repeaters are built, planned, commissioned & used: Steve Morton, F4VTF, G8SFR

[Music] [Music] [Applause] [Music] [Applause] [Music] [Music] [Applause] [Music] so [Music] [Music] [Applause] [Music] [Applause] [Music] hello and welcome to tonight at 8 from the rsgb repeaters have been with us in the uk for almost 50 years and most radiometers have used them at some time or another but how do they work and what does it take to put one on the air tonight we're pleased to have with us the etcc data manager steve morton g8 sfr so a warm welcome to tonight at 8 steve can you give us a quick overview of what you'll be covering this evening good evening everyone yes i hope to give you a brief introduction for those that aren't familiar apart from the sort of operational point of view about what actually goes to actually put together a repeater um how they're put on air what's involved in keeping the thing running and some other background about atcc excellent well before steve's presentation a reminder that if you're watching this on monday the 27th of september then this is live and you can add comments and ask questions on either batc or youtube at any time during the presentation or straight afterwards please include your first name and call sign if you have one within each message and also please note that you can make this video stream fill your screen on most devices usually by double clicking on the picture or pressing the full screen button but now it's time to go back to steve to find out all about repeaters well thank you david and uh again welcome everyone am g8sfr steve forever radiating and um as tammy put me i'm a very tall person as well or a very tall fellow i think he was when she came up with my french kill sign so what do we have about the history of repeaters as david implied that they have been with us for over 50 years i think the first one was sometime i don't know exactly when sometime in 1971 with gb3pi uh at cambridge and that's still on air in one form or another i suspect it's not the same site but um it certainly covers the same similar sort of area and since then of course things have expanded rapidly and through the 80s 90s and even more recently and they've spread from sort of two meters onto sort of other bands from as low as sort of ten meters six meters um seventy sevens twenty three sims and what have you the network is also expanded in terms of how they're interconnected a lot as well now um currently we've got licensed although not all of them on air of course um about 700 repeaters in in uk it's quite a feat sort of keeping a check on them all but we do our best to do that so what is a repeater for those that don't really fully know it it's basically a device hopefully sat on a hilltop somewhere typically that helps connect the users that they can't hear each other you know in this example here we've got a a vehicle one side of the hill and a sort of a portable user the other side of the hill now normally they wouldn't be able to hear each other because of this mountain that's in the way that i've beautifully drawn and the repeater helps people get into communication with each other by one transmits to the repeat and the repeater relays that signal uh to the other users so the repeaters are listening on one frequency transmitting on another and the users are doing the same but in reverse as it were and so they can talk to each other uh relatively easily via the repeater the repeater doesn't really do a great deal i keep cause it enhances the the area in which you can communicate considerably because particularly if it's a well-cited repeater and if it's got internet connectivity as well then of course you know you're going sort of out of region um even out of country even so what actually forms a repeater now given a block diagram of a relatively simple and straightforward here we'll start on the left and work our way across so in my example here we've got a single antenna although they could be two antennas one for the transmit one for receive because remember the repeat is having to do the receiving and the transmitting at the same time um there's no sort of ptt sort of going on and off sort of thing in between overs as it were it's trying to do this thing at the same time so initially um and i've drawn a little simple spectrum diagram here of there's the received signal there's the transmit signal so it has to go we i've drawn in a sort of a bandpass filters basically just keep all the nasties out of the way as much as possible um then we have a thing called a cavity duplex that basically brings together it's another form of filter but it brings together the receiver and the transmitter um together into a common um which we've shown here and what that effectively does is it basically um filters out the transmitter on the receive leg and the oops the receiver is so the receiver is only going to see the incoming signals and hopefully not not much of the transmitted signal that's the idea of that i will briefly mention this ferro isolator because not many people will have come across them um what that basically does is any signals that are coming down the feeder from the antenna potentially get into the transmitter mix with the transmission and then come back out again whereas the isolator basically short circuits stuff that's coming down the antenna and it basically only allows signals to go up the antenna from the transmitter the talk's not long enough to fully describe all of those things but it's like a magnetic um thing that has a direction of flow and signals going in one direction go into the dummy load signals going in the other direction find the way out so the the receive leg down the bottom here that has its own band pass filter as well and that's maximizing the received signals shown here on the left hand side and there's a little pip if you like of where the transmitted signal would be and then that goes into just the receiver which in this case i've drawn it as if it's an analog one so it has ctcss which is a continuous uh tone that it's listening for it's got the actual audio coming out of it and it's got the swap swatch that then goes into the controller the controller decides is this a valid signal or not um has the signal been there too long and all sorts of other features like um idents and timeouts and all that sort of thing and that then in turn controls the transmitter it turns it on relays the audio through sends the ctcss signal to the transmitter for the it to then transmit and we go round the loop sort of thing um there is also hidden here of course other ancillary things that could be coming into the um controller like you know that potentially might be um if the um repeater is battery powered as some of these hilltop ones are if the battery goes low of course it can signal that on the transmitter that um we're on low power or something and and change the output power if need be to sort of guard against that or if there's a mains failure on site for instance it might um try and preserve itself but all that looks that's a very sort of simplistic view of it admittedly and um it can take quite a bit of setting up as you can imagine particularly the filters the filters can be very very sensitive to even small adjustments and if you want the repeater to perform at its best then um the filters really need to be done on site because just transporting them can um shift them in frequency just slightly because remember this thing's trying to transmit a sort of a hefty signal on one frequency and receive on another and they might be only sort of 100 600 kilohertz away or whatever depending on the band in terms of percentage of the frequency it's fairly small so they are fairly critical a lot tighter in frequency separation compared to commercial repeaters which typically are much wider in spacing um hence and we'll come to this in a second the actual cost of the filters can be quite high from a from a group point of view so what else have we got so what is required to put a repeater on air um quite often i get asked this question what forgot to do to put a repeater on air well first of all you really need you have to demand in the area it's no good um sort of suddenly having this brain wave one friday evening saying i'm going to put a repeater on there whoosh it's a bit more involved than that um you obviously need demand in the area that you want to serve with europe so it's a good idea to get some idea of the actual area you're going to cover you know is that covered already by a similar repeater um maybe not exactly in the same town but in this similar sort of area um do you have sufficient funds available um these things do cost quite a bit and it can be a bit of a shock if we sort of say there you go get on with it and then they go oh didn't realize it was going to cost that much um a suitable site one that you can gain access to which is a bit of a sore point i suspect under covey conditions because a lot of people not been able to get to site uh for various reasons particularly if it's on a hospital or site or or similar so a suitably accessible site and the the problem with that is is the cost of sight these days is can be quite prohibitive unless you um got a fairy godmother sort of in the wings as it were um and this is where i come in i suppose suppose the availability spectrum in your area again you might find a suitable site you might not be covered terribly well in your area but to add another repeater in your area is difficult and all the resting and i've got my famous quote of the radio spectrum is already packed and unfortunately they've stopped making any more of it i didn't invent that one someone else did but it always chuckles me when i i see it um for an nov to be issued it has to be a full licensed uh person so you need us if you're not a full licensed holder yourself you need to find one that um that is and willing to take on the responsibility for the repeater you can do help in the background with technical stuff and you know doing all the other ancillary things but there is a responsible person in the form of a full licence holder is the key if you like to um get in the actual nov issue because it won't be issued otherwise and time it's time elements if the repeater is cited at your house for instance remember you are potentially losing the use of the band that that repeater is set in whilst the repeater is going to be filtered fairly well and would most probably cope with you operating reasonably close to it without too much hassle uh your own receiver unless it's filtered as well will not get on terribly well with this repeater blatting up and down in the background sort of thing and so that can put people off the fact that they can no longer use two meters for their favorite uh pastime or or 70 sims or whatever band it is and so i come to supporting your local repeater group because again money and we're being realistic in a way and i asked my fellow committee members for some guidance on this one as to you know how much do these things cost to to put together because i'll be honest i've not actually put a repeater on there but there you go so radios and kayaks you know that's a starting point isn't it we all need that to to put any signal out they're often donated anyway the people helps might have sort of spur kick lying around or some spare lengths of decent coax and you are talking of at least sort of um rg213 you are 67 that sort of thing not rg 58 and similar a decent antenna will cost you um most probably in excess of 100 pounds because don't forget these things if they're on an exposed site they are going to be subject to fairly high winds particularly in winter icing can be a problem and some of the normal amateur commercial antennas have been known to fail um quite so quickly in service then they get water inside them all or similar might be fine on your own sort of house slow down sort of thing but sticking on an exposed site where it's being buffeted constantly it might have all sorts of side effects those duplex filters i was talking about they can be quite expensive particularly for narrow spaced repeaters so if we're talking 70 sems that's the sort of 1.6 meg split 2 meters 600 kilohertz but there aren't no wide split 2 meter ones on 77s we do have 7.6 and 9 meg spacing available which makes it a little bit um cheaper in terms of being able to buy something off the shelf um rigging unfortunately unless it's just your site if it's a commercial site you're going on to the site owner will insist on you using um their riggers or commercially commercial riggers that are full they have you know full risk assessments and full safety um requirements and all the rest of it because they're if they're adding an extra antenna onto the mast they will have done some form of assessment of extra wind loading and that all that sort of stuff so they want to want it done properly and okay you're only going to do that in the initial phase but that can be quite expensive um sort of even as a one-off sort of thing then there's the sort of ongoing um costs of site rental um with the with the the advent of mobile phones and whatever farmers and the like have suddenly got aware of how much their small plot of land is worth on a hilltop and command rents more so than ever before um electricity costs quite often that is included in the site rental or they don't even bother to ask you for it the rsgb can provide third party insurance at 10 pounds a year um per repeat i think that is and if you have some form of internet connection sometimes that's included in site rental i've been told particularly if you get a favorable company or organization and as it says at the bottom there companies are often quite generous in um providing sites uh much lower rent if it's a uh an amateur repeater they're not gonna sort of sting you for you know the full commercial rate they'll give you a slightly lower rate but they might still insist on the commercial rig a bit and whatever you might not get away with that but or you might get away with it in terms of well we'll do a reduced rate but you'll have to wait until the guys are on site doing something else a similar height to where your antenna is going or lower down or whatever obviously a lot of these things can be nibbled down a bit if for instance you're able to put up a mast yourself maybe on the same site but in a separate building or something like that um you know each case really is an individual case but i have to sort of think in a broad sense of saying well what's the sort of typical what's the worst case if you like so internet connected repeaters you know whilst the internet connection at the site is one thing they all connect to some form of system somewhere and these have become um quite popular especially in recent in the last couple years or so and the the actual various systems and there's lots of different ones now different reflectors and different types of server and what have you they're all connected through so you get a mixture of services or mixture of repeaters all connecting into a common um source if you like and they cost money to run you know typically 10 pound a month or thereabouts if you've run your own website you'll know sort of typically what that might cost to run then of course without these servers become your repeater becomes effectively a standalone it's just basically only for the local people i can hear it and and get into the thing so it potentially becomes a lot quieter so i this is a favorite of mine unfortunately you i'm going to bend people's ear a little bit with this one might upset a few people but if you've got a repeater please use it um not you the keeper but you the user there are so many repeaters in my experience that appear to be underused i was back in uk in the sort of london area in august for about three or four weeks the first part of that was doing the wonderful covid isolation bit and i happened to have a handheld with me and i was amazed at how little traffic there was through some of the local repeaters there i did manage to talk to a few people but not as many as i thought it would there we go so put out the occasional call through the repeater just to let you know others know that you are about sort of thing and if you do hear someone call through the repeat do you know respond to them even if it's just a quick signal report and as we all know um some of the bands that we operate on aren't exclusive to us um spectrum as i previously said is in big demand and if we don't use it we'll lose it potentially i'm not saying what or where or when but it's always a potential threat if somebody goes monitoring our actual usage and sees that in a typical 24-hour day a repeat is only active for say an hour or so in total then it all adds up and potentially we um stand to lose things which is a bit sad i know we've done very well to hold on to what we've got now if it wasn't for all our efforts to do that i quite often see my main um job if you like is looking after simplex internet gateways now these are similar if you like in some senses to repeaters except they don't actually repeat they're only so your local user that goes through a simplex gateway isn't repeated by the thing it only it listens to for for people and repeats it via the internet and simply the internet gets repeated on radio i did all quite a longish talk for the northwest fusion group um a few months ago now i don't attempt don't attempt to write down that link just do a search on youtube for northwest fusion group and you should see uh my face pop up somewhere on their channel they've done quite a few uh videos on gateways and repeaters and ian does a great job of explaining these things better than i can to be honest with you but i did a little um live stream with them a few months back explaining how i go about um assigning frequencies for um simplex internet gateways um mainly because we were i was having to turn down too many in their area which was a bit dis dis chuffed for some people but once i'd explained the actual nature of how we go about um assigning uh channels for gateways um people were calmer and had a great better understanding of it you know it's it's a whole different ballgame in a way and setting up a gateway is it's a different set of challenges um compared to repeat with anyone who's set up a package station will understand you've got sort of various elements you've got the computer to set get set up you've got the interface between that and the radio to set up and then the radio to the rest of the world and servers and all sorts of stuff that not even i understand to be honest with you i just treat my my expertise is in this sort of frequency assignment and spectrum management side of things or spectrum mangling of side of things if you like um so as i say that that's a whole different area really really beyond the realms but i thought i'd just mention it tonight really to um say that there is more to um this sort of game than just repeaters so what does etcc do this is the official line we actually receive and scrutinize look through with a fine tooth comb all the actual applications or proposals for analog and digital repeaters gateways package systems and what have you um i like after see all the incoming stuff for gateways and um packet which is about 400 odd um novs currently i get involved in the frequency assignment of all the repeaters that come through as well once um a proposal has been finalized we've we've got the thing into shape and it meets the standards that are laid down by ofcom we then um once the things all agreed with it we then forward that onto ofcom for them to process now that might be a finalized nov that's sent to them or it might be a proposal that needs clearance via the the primary user in the case of say 70 sems or one of the other bands um and that can take some you know several weeks or months even in some cases and so we have to make sure that everything is sort of buttoned up and all okay before we finally send the thing through and occasionally we do liaise with ofcom and other parts of rsgb and user groups and all that sort of thing we represent the the actual committee at rallies and clubs and summer events and event like this for this evening what we don't do is we don't police the bands that's not our remit that's down to um ofcom to look after the bad boys as it were so we we don't go around sort of uh knocking on people's doors or anything like that that's uh somebody else's job now long long time ago i found this book lurking in my bookshelf um the international fm guide sounds for a grand title doesn't it but in that it had all the details and i'm showing on the right hand side here a typical page for gb3pi no less and it had all the details of how to operate news um each individual repeater that was on earth at the time and it also gave listings as well for uh repeaters in other countries around the world that was quite surprising i can't some in those cases it was just a listing and in some cases it had frequencies as well but this book this particular copy that i've got i think dates from about 1987 um well there abouts a little while after i first got to put it that way but um these days you would um go to the internet of course you know it's most fully replaced it's beyond published books and whatever because things change so rapidly so if you want to find out more you can go to uk repeaters.net where you will find lots of listings of voice repeaters data and sim gateways and what have you listed there in frequency order and all the rest of it you can even on some of the listings put in your own qra locator and get hit the sort of calculate button or whatever it is submit button and then it actually calculates the distance to each repeater and if you then sort it via distance order you'll get to find out what's the nearest ones to you or if you're hearing a repeater and you want to know roughly where it is it will give you some idea what the nearest town is and an approximate distance it's not that accurate but it'll give you a fairly good idea of how far the thing is away we have a guide to repeater licensing which sounds uh it's a great cure for insomnia at night reading through that it runs to several tens of pages and i sort of put help put the thing together again that link is long linked but you will find we'll obviously post links to this further later on um it does have a step-by-step guide to filling out the application form if you're putting in an application for a repeater a simplex gateway or a package system or whatever they all use the same form but in slightly different ways i suppose but what i've done is i've done some screenshots of different sections of the form that you have to fill in and then there's explanation notes underneath each screenshot sort of thing there's a there's about six or seven sections i can't remember and well going back in time there used to be a an mpt document which is dating back to when um the days of the radio comms agency and before that even it was the mystery posts and telecoms hence mpt and they put together like a standard or best practice for radio site engineering and subsequently that document's been taken on board by the federation of communication services or fcs and they've sort of updated it it's a really good document to read through and if you look at that address there to fcs.org uk slash best hyphen practice it's got lots of good tips um on putting together radio systems particularly on shared sites so not just shared with other amateur users but other commercial users as well and the sort of practices you need to adopt um before you consider it before you even think about doing game but it's got lots of um detailed stuff and it's very practical as well of course rsgb.org and that is it from me so any questions over to you david thank you very much steve and as you say we're going to add those links onto the youtube channel in the next few days um so that people can click on them and refer to them but if you'd like to ask a question of to steve and you haven't already done so then please do it now on either youtube chat or batc messaging and please don't forget to include your first name and your call sign if you've got one and actually just mentioning something like that special mention i think has to go to a gentleman called matthew fowler who put a note on there that he passed his foundation license today so um well done congratulations from all of us here at the rsgb matthew and we hope you enjoy the hobby so steve let's get on to our first question we've got a question now from sean finch who says can a repeater have joint holders unfortunately not no it's the actual um nov is under one person's on it's a notice of variation on a call on a license therefore it has to be one named person now in terms of canopy joint there has to be a named person that's authorized to turn it on or restore it to power if there's been a shutdown of some case now whilst that's a named person that person can delegate it to someone else but as long as they're they know that it's been turned on the other person just doesn't turn the thing on just because oh i found it switched off i'll turn it back on again sort of thing so now unfortunately it's actually attached to one person's license therefore it has to be only under that person's license and not someone else's also it can't be a club call sign it has to be an individual's full license yeah i was just going to actually ask you that steve um just extending it slightly could it be a club or an entity like that but it has to be an individual person basically yes who's basically taking responsibility for it i guess yeah okay um now we've got a question from tom mm6 irq says does the rsgb compile any statistics on operation costs from upholders of repeater novs we haven't um done it as an exercise but i'm sure if people were willing to sort of send in the the details we would be quite happy to sort of put it together and put it together as sort of a report that we could put on the website at some some stage it's not something i've thought about i must admit but so yeah it then it might give um others more sort of reflective cost of you know you did this survey in 2021 and 2023 that the prices have gone up or gone down or whatever okay thanks um sean finch has come back with another sort of part b to his question as well does a site relocation need a full new application yes it does because so many things change and it's if it needs to be re-cleared um then i'm sure they don't want to take the existing repeater off air sort of whilst we're getting clearance for the new site sort of so yes it needs a full application okay thank you now the next question comes from eng0 vgs from the north west fusion group says there's quite a responsibility in running a repeater you're responsible for the traffic through it and it's worth stressing that that you're sure that you really want to do it steve is what he says yes yeah totally great okay um it's quite i'll say it can be that that's where the time element comes in because you are expected to as the nov holder you are expected to monitor it from time to time to the best of your ability not necessarily at night obviously because you're asleep but i think the nov says you'll make a reasonable effort to monitor the traffic through your repeater reasonable being the operative word there will let ofcom's lawyers decide whether you were reasonable or not so if there was someone playing music and not being identified or abused or something like that on there ultimately you're kind of responsible for at least trying to do something about that yes okay um there's quite a few people chatting on here by the way enjoying your talk steve as i'm sure you'll agree i'm just gonna it's lovely to see also lots of people watching from all over the world in fact as well i've got a question now from carl clark why do you think that we do not have more aprs coverage not just gateways but transmission good question um it could be that you know people have lost interest in it maybe i don't know it's it's definitely a thing that's died down compared to when i first got involved in packet radio back in the late 90s you know what things have moved on people have gone and went away from packet and sort of voice sort of came along and sort of took over from it in terms of interest um basis we can only react really to the sort of demands i think back to the 90s we used to have uh six or seven different uh packet channels we're down to sort of three now so and that's really we're sort of reacting to the demand for spectrum and what have you we have to reuse what spectrum we have um obviously in the case of aprs of course it's just two frequencies so of um 144 800 and 433 800 where it's not available but uh you know i don't know i don't honestly know people maybe it's the difficulty in sort of setting up that type of station because there's a few extra hoops to jump through isn't there in terms of the actual technical side it's a bit easier on in some respects i suppose but um compared to what it used to be like i think um we must be blessed here in norfolk because i can speak from personal experience because i run at what's called a digipeater which is an aprs repeater as you know and there's several of us here in norfolk and we do do it by radio but i realize that that's you know that's not going to be everywhere but i think we've pretty much covered norfolk with our norfolk aprs group certainly packet overall not just aprs but packet radio in itself is not fragmented but it's in small clusters of activity if you look at our listings you will see that scotland has quite its own little network of stations several of them together and then it's it's sort of isolated areas as you said norfolk is fairly well covered for aprs and what have you but it there's no real limits on them there's no sort of so much there isn't as much of clashing of um operations with with pakis you know it will sort itself out if it's a busy channel and because we're using just two frequencies of the spectrum we've got a question now from steven mcbain is there a process for the transfer of an nov to a new keeper where the old keeper is medically unable to sign it over he's he says this because he's waiting for a response from our local rep but thought that he'd ask you now yes it's a difficult situation that we've we have had this problem um to deal with several times over even when a keeper has passed away which is rather sad when that happens of course and of course then you don't we do have a change of keeper process um so if the both parties are alive and kicking and talking to each other and what have you that is fairly simple and straightforward one the actual existing keeper kicks the thing off names the new incoming keeper and then we take over from there and we make sure that the incoming keeper is happy to take on the responsibility he's not just been sort of landed with it unannounced and once it then gets transferred into the new keeper's name we go back through the application and tidy up a few bits and pieces on that like the close down list and stuff like that and then a new um what then happens is once both sides of it are agreed i either the outgoing keeper is happy to hand thing over and the incoming one is happy to take it on what goes to ofcom is the new nov and the new keeper's name and a second nov in the previous keeper's name now that's fine i realize when everyone is compos mentos and everybody's happy and all alive and kicking whatever but what about the situation that you've just described there where one of them is either incapable or not quite you know medically um not quite with it sort of yet we have used in that situation where the person has a i can't remember the name of it now where somebody takes responsibility like a guardianship of their affairs normally this would be their bank account and their health is this a power of attorney that's the word i was looking for yes so apparently if someone's got a power of attorney then we can take it from there and if need be we've even had submissions done via a very short video call or a video message type thing um just basically to prove that they are the the person involved and what have you if you've got that situation in hand at the moment then contact your local atcc rep or the etcc chairman both available via repeaters.net and they will help try and help you as much as they can to sort through that issue worst case comes the worst what will most end up happening and this is the sort of worse situation is the nov doesn't get renewed and the thing just sort of times out after the three years is up so um then of course it goes back into the melting pot and you can start again but you don't want to do that because it's a lot more aggro starting from scratch compared to being able to transfer it from one person it's just another occurs to me steve yeah i just wonder if there's a possibly a case and i don't know whether you'd be able to do this maybe someone a repeater keeper could actually name somebody who in the event of them becoming incapacitated because they're ill or because sadly they're passed away just someone to take the the mantle and and um take a bit of responsibility for the repeater while it's being transferred yes what you they can do of course is that in they can put together some form of statement or document in the case of my incapacity i give the um go ahead for the this nov to be transferred to this named person or whatever and then lodge that with the power of attorney or whoever it might be um it's sorry suddenly it's a more occurring fact these days because we're all getting older the amateur population in general is getting older so it's it is happening more and more often unfortunately okay well thank you whenever i see um silent keys pop up on rsgb news i must be i do sort of quickly scan down the call sign list on the gateways and things to see if they're one of my customs as it were yes it's a sad thing but it happens okay well thanks for explaining the position on there um we've got quite a few comments and things and nice to see the chats in between people we've got a comment from mm0xet not really a question but just says that gb3ag has a storno radio fitted uh the repeater box was built in 1974 as in and as still in use even with a 1750 hertz tone cheers gary they said that's lovely to see isn't it now our new licensee today who passed his uh foundation again today matthew fowler says thanks for the lovely welcome can i digit personal digital hotspot uh brackets 10 milliwatt power type for gatewaying dmr to the internet linked networks be run by a foundation license holder no sorry oh dear he's obviously done his homework don't be able to ask a question like that i think yeah good for him to start asking that question yes gateways are the exception to the rule all other novs that you can ever think of and there are lots of them um are all worded with the word full licensee and including the gateway nov is like worded with the words full licensee now as i say there are lots and lots of different types of novs more than i cover i only cover a small segment on and i'm i i quickly think of people wallpapering their shack with them and they seem to collect them there's so many some people are issued with so many of them for different things most of them are repeaters but the odd the exception to the rule is gateway um novs although and although it doesn't say full and intermediate radio comms agency my old employer from years ago gave a concession in i think it was around about the year 2000 to let intermediates run um a simplex internet gateway initially it was on an attended only basis but that was broadened eventually to allow them to run the unattended ones as well subject to them providing the full um close down list and all the rest of it um ofcom agreed to let it carry on um for the time being if you like and they've never sort of muttered anything about sort of taking that away but unfortunately for foundation licensees you'll have to pass your um intermediate exam before you can do a gateway to do um relaying of dmr and what have you even at such low power the power doesn't come into i'm afraid it's the handling of third-party traffic and other such things now what one other exception there's always these exceptions and it's a bit of an oddball one we are allowed to issue foundation licensees and intermediates with receive only aprs gateways now you might think why are you issuing an nov when there's no transmitters involved it's simple signals that come into your gateway can reappear back out after they've gone through the internet out the other side on rf and therefore it's sort of best practice in a way that the root that these signals took were what via mb7 stations so in other words ones that held an nov i know there are people out there that don't necessarily agree with that approach but we don't stand in the way of people that want to do it with an mb7 call sign on a receive only basis and what what do they use something as simple as an rtl sdr receiver you know all these little tiny dongle things i've got one kicking around my drawer here somewhere um that literally is a usb stick which you plug an antenna into with some magic software on a raspberry pi or similar it can listen on 144 800 and grab the frames and relay them to um aprs.file in finland i think it is so there are quite a few of those around and um as i say we have we do issue those as mp7r so are being received um just to make sure it's clear is that they don't transmit sort of thing when people see them come up in listings and things or on maps or simple stuffs like that well there we are matthew there's somewhere to go and dare i say as well it might be a good incentive to be start thinking at some point about your intermediate but enjoy your foundation first um a few other questions now sean finch has come back and said is a circulator actually required or is that a recommended item to add into the tx path it's only a recommendation but you'll find on some commercial sites it's uh you know you will you know you'll sign some form of agreement to go on a site and one of the things they expect you to use is circulating because basically what it's doing is it's stopping into mods being generated on site and on a very large busy site the number of frequencies being transmitted at the same time is you know can multiply upwards quite rapidly and all the enter mods again it's just like a comb you know you see three transmitters come on and there's all these little like hairs come up from the sort of bottom of the spectrum it's actually becoming a problem for amateur only sites as well now because if you think about you could could have a couple of 70 sems transmitters one for analog one for digital and you might have a sort of a two meter one and if we've not been careful and the two seventy sems ones are six hundred kilohertz apart when the two meter one transmits at the same time as the two seventy sevens ones you've got a signal popping up 600 kilohertz away from the 2 meter transmitter no matter where it is and it sort of deafens itself as it were yes i made that mistake once never again we check against that one there okay but yeah it's only a recommendation but you might find on some commercial sites and i've got picked that up from the fcs um guide that they'll insist on you having a circulator okay thank you steve uh stuart g3 ysx has says do you think we will see single frequency repeaters based on one of the digital modes such as dmr we do have them already there's one in stoke-on-trent where it's uses two time slots so it uses one time slot to receive on and it transmits on the other timeslot so it's single frequency but it does the sort of receive transmit to receive transmit and of course by being able to do that it um reduces the requirement for filtering it still has a bandpass filter because it's sites with several other repeaters in my of it but it doesn't need the very narrow bandwidth um cavity filters it just needs a simple bandpass filter okay thank you very much steve um graeme bohr i've just seen the question they've got quite a lot of questions still coming and i hope you're still okay oh yeah yeah an hour later for your course in france at the moment yeah um graham boris said what's the situation on remote close down he seems to recall that you had to specify that as well as the closed down operators yes right if we go back i've been doing this stuff for 27 years or so and if you go back that far in back in time we used to have to provide six closed down operators um any three available at all times or and all available within 30 minutes traveling time of the site and then no remote close down was permitted back then it all had to be get to site within 30 minutes and physically shut the thing down wonderful no end of problems doing that especially with when people moved house and didn't bother telling the keeper and they'd move from one end of the country to the other things got relaxed um i can't remember the exact dates of these things around about mid 2000s i think from memory where that requirement was dropped to four um closed down operators the three available at all times disappeared thank goodness and they sort of said you can have remote closed down if you want it's then gone further relaxed even more so and they've said well we've got the keepers details the additional close down operators is an option now we actually as a courtesy thing ask for at least one extra one in case the keeper is on holiday and out of the country or whatever or isn't available or can't be um contacted for whatever reason but by relaxing that part they've insisted on the um repeater or station being able to be shut down remotely from anywhere so outside of the coverage area not just inside the when we had it from within the coverage area you could simply use sort of dtmf tones on the receive frequency or something like that well that's okay but obviously it's useless for simplex systems because effectively it's potentially blocking itself out so what we recommend now to meet that requirement in the case of a remote site that doesn't have any internet connection to it something like a gsm controlled power socket and you can look these up on amazon though fairly freely available or in the case of it's if it's at a home site or you have internet connectivity available um a wemo um type power socket which uses just wi-fi to connect there's there's pluses and minuses to both type of systems with the wemo ones you need a smartphone basically to operate the thing with the gsm ones even an old nokia you just send a text message to the thing or you ring up the number and that toggles it basically turns itself off now so that's that's the situation fortunately in all of the history i have of being on atcc and dcc and all the rest of it the number of instances of being asked to turn off a system are fairly low very low in fact i can't remember the last time i was asked to um contact a keeper to get the thing turned off so it's best practice to be able to um include that facility to just for your own peace of mind if nothing else and it can help of course um if you're remotely monitoring um your transmitter via the internet or you're listening via the internet and you're away on holiday something and you do hear your repeater being abused or whatever you will be able to remote control the transmitter and turn the thing off remotely um not have to like ring up your friend who's saying no sorry i've got a dinner date tonight i can't go up to the site and all the rest of it or it's heavy snow here haven't you looked at the weather forecast i can't get up there or whatever no so the technology's there anyway and of course yeah because we're all interested in technology itself it shouldn't be too difficult not expensive either that's the beauty of you and it's available you know from your local amazon right um now this is from james m0za says that are there any duplex regenerative packet modes a node still active and also he mentions ian very much enjoyed your document from 1997. oh yeah yes there are no regenerative nodes around these days unfortunately um that's something i was in uh involved with back in about the late 90s in the kent area and there were several of them around they basically listened on a package frequency listened to the start of a packet and then restarted re-transmitting that packet having regenerated it more or less simultaneously so several stations could work via this sort of hilltop regenerative node they were sort of effectively replaced by the sort of digital repeaters we think of today in voice repeaters they're basically carrying out a similar function once they're open um and are sort of transmitting they're basically just re-transmitting a data stream digital voice data stream in this case now whereas i was doing it with 9k6 packet long time ago i've still got the kit i can send it to him if he's interesting just one off if i can ask a question as well just you now live in france as you said i think how different are things like repeaters and things in france are they very active repeaters more active than the uk or less or there's quite a lot of them they do some real oddball things they have linear transponders here so you go go in on one band and you appear on another band altogether and it'll take all sorts of signals um within the bandwidth of the thing as well until a few years ago digital voice was illegal here in france which was quite bizarre um and so d star or something like that yeah d-star was not you couldn't you couldn't run d-star or fusion or dmr or anything like that on the amateur bands it was quite bizarre and i have to say rsgb and the people in the community helped our french counterparts um get it legalized and it's now now widely used over here as well or it's spreading put it that way okay good thank you um so we've now got a question from keith m0kil um he says i spotted a crossband repeater 28 stroke 50 megs on the listings are these popular no that's the only one [Laughter] and you will note in that case it's between two amateur primary bands that's important because um there is a difference between amateur primary and amateur secondary bands in terms of getting clearance for these things that particular one does operate as a can operate as a full repeater on on each band but they can be cross-linked um on the actual within the sort of control side of things but i'm not sure if that's one stellar or not to be honest with you no it's still in the listing okay i think there's quite a few people trying to help matthew about with this question suggesting just summarizing for you because i know you can't see these questions yourself about they can do personal hot spots and things like that dav m0wdv has said the 70 centimeter band plan refers to 434.00 low power non-nov personal hotspot usage so if no nov is required for a personal hotspot surely an m7 could do this he says yes but as long it's a personal hot spot where only he can get in and out of the thing it's not for relay relaying other stations so if another station can get into it and be relayed by it it's no longer a personal hospital right i think therefore just for yourself as an nov yes so that sort of typical usage might be um you've got your antenna up on the roof and you just happen to be sat in your garden with your handheld sort of thing and you're talking to your friends that are on the way to you to come and have a barbecue or something similar like that but be careful about that because um the license is very specific if you look and i'm doing this from memory uh 10 6 and 10 powers 10 7 of the license 10 7 i think is the one that covers intermediates and foundational licensees where it says remote control of the station which effectively what a hotspot is um can only be done by amateur bands it meant doesn't include via the internet whereas a full licensee and whichever way way around that those two paragraphs are says any means of any communications links as long as they're secure so it allows them to use amateur bands and any communication links which my interpretation my personal interpretation not an official interpretation um basically means internet mobile phone or whatever how did we get on there because we're not supposed to send encrypted information over the air are we as amateurs no we're not okay i don't know the answer either i'm posing the question so if it's a publicly available coding system i know so let's say you're using uh jesus fusion system or icom's d star system they're commercially available aren't they they're you can decrypt them i guess and you can decrypt them using sort of other means of doing you know you can have an sdr receiver that will listen to all um aor i think do an actual receiver don't they which will decode dmr d-star or fusion and a few others as well sort of thing okay thank you uh we've got uh john m7 bcc now says if a repeater has someone trying to interfere with its running and causing serious disruption to other users what actions can you do to bring the culprit or culprits to task i'm not going to suggest physical violence no there are procedures aren't there yes there are procedures and i must be honest i don't get involved in that sort of thing myself in terms of sorting out there is like an observation service part within um rsgb that they take reports of interference and abuse and you know band where peop our commercial station might be operating within an amateur band or whatever and they sort of take these reports and they interface with ofcom or whoever once they've built up the evidence that this is um not just a one-off instance or you know it's been reported by several people or whatever and then they they hand it over to ofcom who hopefully uh hopefully will take some action if they believe that whoever it is is breaking the terms of their license or the wt act or whatever okay and if it's a case of um foreign interference it's uh stationed in another country altogether a commercial broadcast station that suddenly wanders into one of the hf bands or whatever they will talk to the equivalent their equivalent of ofcom in that country and ask them to deal with it sort of thing okay so i'm admittedly my answer is a bit broader than just repeater interference but i think like you my recollection is the rsg we have a department though that deals with this sort of thing either oas or something like that be on the website so yeah if you do get um reports of anything like that or you experience it yourselves then um and it's not i think the general approach is not to react yourself to these just pretend they're not there and then they go away a bit bored because they're not having any impact or they don't think they're having any impact yes um jonathan nuttall says modulation and encryption are two different things uh digital modes are modulation encryption is hiding data or comms behind the modulation um other people stewart uh g3y6 saying that he believes that crypto authentication is allowed i guess we're getting a little bit off the subject repeaters now but but you know it's all interesting stuff it doesn't matter absolutely good yeah and sean finch has come back and said does a an fm analog repeater again need a new application if the keeper decides to run the repeater with an internet connection i.e hub.net etc no para 2 of his repeater nov okay states that he can connect the repeater directly to other communication sources or other networks i think it's it's worded out it's not particularly well worded or it's not particularly obvious in the nov what the actual para 2 means but it basically means he if the repeater is at a suitable site that can have an internet connection direct to the controller he doesn't need an additional nov to connect it to the internet if the internet connection is via a radio system i.e via an amateur band to say someone's home location and the internet connection is at that home location then yes an nov is required for that link and they'll come to me for that because i'll process the thing and in fact effectively you're on the repeater frequencies but the nov for that is specific for linking to that particular repeater it's not just a a general one where you can sing well connect to this repeater tonight and i'll connect to that one tomorrow night you if you wanted to have um links to two different repeaters for arguments say you'd have two novs more paper i'm yeah okay um i thought we were almost over the questions because they've gone longer than your presentation and by the way i should put in this point a moment ago we talked about repeater abuse in fact indeed any on-air abuse yeah and my colleagues at the osgb have come back when talking about the operating advisory service oh there you go and if you want to know details about that you go to this link it's rsgb.org forward slash oas so it's rsgb.org the usual rsgb web address and then oas which stands for operating advisory service so if you hear or experience any abuse and that sort of thing then that's the place to look for that so a couple more questions for you if i may ray m0ray says is it possible to chat through the packet lonnie uh link person to person l-o-n-n-y that was link person to person i used to do this years ago although to the annoyance of the local sysop system operator i guess when i used to live in the northeast and that's m0 roi it is no longer in existence it was turned off many year many years ago um there were a lot of these systems that were questionable in the legality um because prior to 2000 or 1999 maybe i can't remember which um connection of a station to the internet was not strictly within the terms of license now remember the license back then was the old br 68 as was and it was very worded very differently to what we currently have in our um lifetime license which is a bit clearer a little less loopholes in the thing and less gray areas but now lonnie disappeared long time ago i think in actual reality and i can't remember don't quote me on this i think the chap that ran the london end of lonnie which was london new york and fire and and nbc had an office in london and an office in new york i've just maybe i'm slow on the uptake i've just realized that lonnie stands for that london new york london new york and it was literally a packet link from center point in london via paris to um i think i can't remember what the building was in new york it might have been even been um in the world trade center or the world world trade center yeah maybe i don't know anyway whatever and yes you could link through lonnie as if it was just you know a point-to-point link and you went literally tunneled through this thing and you popped out the other end and you suddenly ended up seeing all these other packet networks with american golf science it was quite quite a novelty and of course before the internet that really would have been something unique wouldn't it yeah there were lots of variations on that um when it came to packet radio mailbox forwarding we of course we had satellite forwarding where um a couple two or three stations in uk were set up to collect the mail wait for a um satellite to come over and then they'd squirt their little bit of mail via the satellite and it would be picked up somewhere else in the world sort of thing roger g3 ldi in in your part of the world david used to run one of them yes but yeah i'll ask him about that then because that sounds fascinating so it was kind of center's packets and then cast almost and then resent yeah down to earth yeah and then there was an interesting variation tried um and i don't think this was documented or known about but i won't it won't give any names or call signs away but there was a system on a cross-channel ferry that used to go to the channel islands and steamer net that was it would pick up the mail or whatever um when it was in harbor in southampton or portsmouth or somewhere and of course it then did a four hour journey across the channel islands or however long it takes and then local mailboxes there would would collect the mail when it came into port sort of thing and then they'd send it back the other direction and then there was um postman pat forwarding in the form of i think up in some of the remote parts of scotland where someone would literally put um mail messages and bulletins onto a floppy disk and put it in the post and it was taken by the postman to the mailbox at the other end of the country brings a new meaning to packet mail then yes something like that yeah yes a lot of these have all this there is some hf forwarding still going on but it's very you know it's literally uh i think one station in catrium that still handles a lot of that sort of stuff uh paul if you're listening tonight hello um he still runs more or less a similar sort of network that he was running back in the um 2000s almost and he's his website gives full details of the links that were there and what still is there now sort of thing quite fascinating thank you yes um jonathan nuttall says if a repeater is down for an extended period can its nov be revoked before its expiry um we don't have the power to do that um we can we monitor um when someone reports a repeater as being offered so there's there's two two periods there's when the nov is first issued ofcom give us three months notice that the repeater should be on air within three months if it's not on air in three months they don't start jumping up and down and start banging doors down or anything like that but they do sort of think well is this thing going to come on air or not or has the application been put in to block someone else from putting a repeater on in that area so automatically we send out an emails um at the three-month period after it's first issued then if a repeater is reported as being non-operational or on low power or similar we monitor that situation and then again automatically we generate an email that goes out to the keeper after six months and they then get the option of no it's back up it's operational again sorry i forgot to tell you no it's not operational yet and that just basically resets the timer or sorry i can't you know this is just proving too much of hassle for me to get thing running again or the thing is broken and it's costing too much money or whatever and they this is a bit complicated because they call the counselling of an nov a second nov that doesn't mean you've got an additional one it's the terminology for saying to put your license back to as it was before you had an nov and unfortunately they called it a second nov okay so it's effectively cancelling out the original nov okay one last question i think for you now and you've well-earned break this is from sean finch he says this is his last question from me if a repeater wishes to have its currently licensed rf output raised can this be done and if so how there is a limit to how high we can go normally um and again you won't find this in the license anymore because the bit that was in the license under br68 days was removed but notionally we've worked on the basis of 25 watts erp for remote sites where possible now where a repeater is within an urban area or within a town that is normally reduced to sort of 10 watts because particularly a 77 repeater it's operating in amongst lots of low power devices you know key fobs and door openers and all that sort of stuff and a repeater has a lot of potential if you like to block the operation of those now whilst a low-power device has no legal um protection against interference um unfortunately your neighbors jumping up and down um can be a little bit off-putting to say the least or somebody turning up at your doorstep with a baseball bat in their hands saying you can take that thing off here because i can't get in my car in fact the key still works you know put the key in the lock and turn it that is beside the point but now if the problem we'll have though in most cases so if let's say we've set the power at say 10 watts and you say well 10 dbw that's that's okay but we'd like it a bit higher the problem will be one if it's on a secondary band we'd have to get the thing re-cleared again so we'd have to go through the operation again and it might get turned down even on the same frequency it has been um so it might be turned down completely so you'd be without a repeater altogether in that case you wouldn't be able to sort of come back on air again the other problem we would most probably have which is more likely before you can get to that sort of issue is in some areas we are so tight for spur channels i'm looking at you io 83 northwest of england not that i have anything against you i come from that area himself that virtually every channel two meters on 70 sems they're all in use somewhere and so increasing the power in that area is difficult because you know and i've done this with gateways where to try and you know add another one in i might have to move in frequency terms some of the other ones which works wonderfully in that local area but it has like a ripple effect you know you're passing on the problem to someone else further away sort of thing and you you then end up with a situation with you've solved one problem but you've generated one sort of 50 kilometers away which you can't solve um but if you've got a situation where you've you only put in for say 5 watts and you want to raise that to say 10 watts that might be per perfectly feasible but come and talk to us before you even consider putting in another application talk to your local rep talk to me talk to anyone on on ptcc about the issue and then we'll see you know is this possible we can have a quick assessment ourselves to look at the situation and say yeah we think that'll go ahead so yeah go ahead and put in in the case of change those sort of minor changes you can can normally just change the existing application and then we'll just generate the paperwork accordingly okay steve well thank you it's a huge range of uh huge subject and a huge range of questions that you've answered tonight so thank you ever so much for covering those and thanks to you as well at home for putting all these different questions to steve yeah thank you yeah it's been interesting brave of you putting up yourself for all these different questions on different aspects of repeaters but thank you very much indeed so thank that does conclude this webinar and thanks once again to steve morton and g8 sfr we hope you've enjoyed this tonight today and you'll be able to join us next time we'll be finding out about the journey and development of the exciting range of sbitex sdr transceivers now if you'd like to see details of that and other webinars or to send any comments or feedback to us please visit rsgb.org forward slash webinars now before we go just time to tell you that the rsgb is holding its 2021 online convention on saturday the 9th of october and you are warmly invited here's a quick look at what to expect [Music] and we really think there's something for everyone at this year's convention and hope you you can join us you can find out more details here at rsgb dot o r g forward slash convention i hope you'll be with us and a reminder that if you subscribe to the rsgb's youtube channel you'll be notified of all upcoming tonight at 8 webinars and the convention as well as other new videos and presentations from the society on a wide range of amateur radio topics so until next time this is david g7ip signing off and clear bye [Music] so [Music] so [Music] [Music] [Applause] [Music] [Applause] [Music] you

Channel: Radio Society of Great Britain

Views: 962

Rating: 4.909091 out of 5

Keywords: RSGB, Radio Society of Great Britain, radio amateurs, amateur radio, repeaters

Id: BqKiB4s94IQ

Length: 89min 25sec (5365 seconds)

Published: Mon Sep 27 2021