Marconi Mark VIII - Color Studio Camera : Getting it working

[austvarchive]

I've finally been getting around to setting up one of my Mark 8 studio cameras from marconi. So far the CCU and main PSU seem to be working ok but when turning the actual camera head on, the fuse in the main PSU blows each time.

The suspected problem is in the internal PSU module in the camera, which i replaced the main power transistors and capacitor but the problem still happens

I wondered if anyone here has experience with these cameras and may know what to try next? My knowledge of electronics is very basic.

My CCU's appear to be missing the apeture corrector boards as well, i am told it will still work, just the images wont be as sharp. Also i seem to be missing the extender board in my camera, and instead the board is labelled "geometry corrector"

I have a leitch SPG-110p to provide the pulses but the color bars from the coder are coming out in inverted colors...i am not sure if my equipment is faulty or i have just set it up wrong as i havent a manual for it

If anyone has suggestions or can help with getting this cam going, i would be grateful for some assistance

[austvarchive]

photo of the camera

[ppppenguin]

The Marconi camera expert is Paul Marshall who posts here occasionally.

Assuming you are working in PAL, inverted colours are likely to be due to a reversed PAL switch. I don't know if this camera takes its PAL sequence from the burst blanking sequence or a separate PAL square wave. Or is it late enough to lock to colour black rather than use a full set of pulses?

[BrianSummers]

Hi

I have sent you a long email with some thoughts.

I like the MkVIIIs and they are mendable and worth persevering.

Brian Summers

[obtv]

hi Brain I have just joined the forum did you get you Mk8 going I worked on the old beast for 18 years I maybe able to help.

[BrianSummers]

I did indeed get my MkVIII Working it's one of several that I have, I'm sure Austvarchice would appreciate your thoughts.

Brian S

[austvarchive]

i certainly would love to hear from you, my email is [email protected]

[XDCAM]

Can anybody please tell me where to find the 1A14 Board on the Mrk8 camera please ?According to the test screen I'm missing this(Focus Current /Voltage) .Have you got a circuit of this also please ?

[NewVista]

Did all Mark VIII's produced have 30mm tubes ?