The Pye Mk6 broadcast television camera - as used by the crew of MCR21

[Music] this this camera the pie mark 6 from 1963 is the correct camera for our outside broadcast fan mcr 21 there are four surviving cameras they were all in the care of the national media museum and we managed to get them to de-acquisition one for us and this is it and by a remarkable coincidence it's actually one of the ones which was used on mcr 21 21-4 the fourth camera for mcr 21 now it's quite a big thing and it's interesting to decide where to start on such an explanation of this perhaps a good place is to start where the light goes in this is one of the lenses this is a three inch lens which is a very common size and it fits in there like that and the iris is driven by the iris motor there which drove all four lenses in the same iris setting so that when you change lenses there wasn't an apparent change in scene brightness so what happens next well the light goes in there and it falls upon the camera tube now you may think this is a big camera and this is why this is a four and a half inch image imageofrican tube and at the time it produced the very best black and white pictures that were obtainable at the front there is the image section in the middle is the target section then we have scanning and right at the back we have a electron multiplier there a dynode system which increases the output of the tube considerably but a big tube makes for a big camera put that down safely so when we look inside this chassis is a scan chassis and the camera is hybrid it's part valve and part transistor but i don't know if you can see it down here that is the scanning yoke which the tube fits inside and here we have the line scan for the camera and the line scan for the viewfinder viewfinder it's quite nicely made very traditional construction underneath the chassis are the components there's quite a lot as you'd expect the capacitors the resistors one of the things that i really like about cameras of this period is that each component has got its part number here we are three two one three one six and that's a very great aid to servicing on the other side this is the head amplifier that takes the signal from the tube amplifies it and sends it down the camera cable which plugs in there this panel deals with various pulse circuits and the cable compensation switch there one of the things when you have a very long cable you lose high frequencies and they control their compensates for that loss the smaller chassis there is a servo amplifier for the iris control in the camera control unit there's a large lever uh which controls the iris and um the vision control engineer would sit there on outside broadcast as the sun goes in uh he opens the lens as the sun comes out and he closes the lens like the line scan side it pops up to reveal underneath the individual components that bit of electronics there is for the viewfinder and there's a tube here with a fan motor at the end for cooling comprehensive talkback controls so the cameraman can hear the producer program sound and reply to either the producer or to the engineers this is a 7-inch viewfinder it gave a very bright sharp picture and one of the interesting features is this little row of illuminated indicators here the red one is obvious that's the cue light you're on air but the green ones there indicate which lens you've actually selected as an aid memoir the little door here at the back allows access to the rear of the tube and the tube is fitted in here it's difficult to get out but part of the yoke comes out and the tube can be fitted inside it and replaced this control here is that in shot is where the turret change crank handle fits so you once round to change each position of the lens that's missing we're probably going to have to have that manufactured now the focusing on this type of camera is done by moving the tube the lens remains fixed but the tube itself moves backwards and forwards and on this canaled device here is a free-spoked focus control so that you can move the whole assembly backwards and forwards and achieve pin sharp pictures well that's the theory anyway a lot of thought has gone into the design of the camera little things like here there's a socket here so that you can plug in perhaps an additional light power for your autocue or your soldering iron or even your electric blanket what else have we got on there would be the camera number camera 4 in this case and on the side would be the bbc logo we've yet to refit these they got detached at some point background to the front the four lens stations a cue light and a large cue light and if you put it on that way it's dim if you turn it around for 180 degrees it's bright additional outputs here for program sound and talkback cameras never stand alone there are always other people involved it might be a floor manager or somebody pushing the camera tripod and there's a pair of jacks here which the person can plug their headset in and the volume controls to adjust the program sound or the producers talk back two more sockets for auxiliary people this connector here is the main camera connector which goes off to the camera control unit an indicator there that parallels up the indicators on the back of the viewfinder so that the camera trolley pusher for want of a better word can see what lens is involved and finally there's a video output there which you might use for the autocue so you can power the autocue from the socket on the other side and take the video there and it would fit here and you would never know that the presenter was reading it well that i think uh is a brief guide to the pie mark six camera i forgot to mention earlier when we were talking about the tube that this is possibly the most complicated valve that was ever made it has an image section a target scanning and in there there's a dynode multiplier and they were hideously expensive no they were really hideously expensive and one of the things that broadcasters needed to know was how many hours the tube had done but you needed to know this for the warranty so i'm just going to pop that down trying not to drop it and here is an hour meter it measures the run time for the tube and this one is 2307 now i don't know if that's been round the clock once or twice even but in the years since it was made it was made in 1963 and it saw bbc service well into the 70s and then amateur service and then here we are today putting it back into use [Music] you

Channel: MCR21 - the life and times of a 1960s BBC OB van

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Id: 5eVLQcHxKdQ

Length: 10min 14sec (614 seconds)

Published: Tue May 03 2022