Head amp for a vidicon
 

Hi, I have been working on a Vidicon camera. I got to the stage of getting some simple hand waving images up in front of it but my RCA head amp died, and I am wanting a schematic for a head amp for it to make my own. I have a few head amp circuits I have used on a PMT camera, but i am not sure this is good enough for a weaker vidicon signal. Well I think its weaker, the PMT gives a nice signal right out of it. Has anyone got something handy I could have a look at.
http://www.taswegian.com/NBTV/forum/...=2564&start=30

Re: Head amp for a vidicon
 

Hi, somewhere on the web are details of the PTV vidicon camera which had a simple mosfet circuit as a head amp.
There was also one in the Mullard educational series of publications

PM me if you have no luck and I'll see what I can find

Ed

Re: Head amp for a vidicon
 

Seems it's normal practise is feed the target signal into a cathode follower, emitter follower or source follower.
From the TV camera museum:

http://www.tvcameramuseum.org/pdfs/p...rcuittvc1a.pdf

It's likely you have visited this site.

DFWB.

Re: Head amp for a vidicon
 

The last time I worked with vidicon/nuvicon tube cameras they had 3 long tailed pairs of fets mounted close up around the edge of the lens.
If we are lucky I might have a circuit diagram but if not I might have an old board for reverse engineering.

Re: Head amp for a vidicon
 

Thanks for the Saticon camera circuit i in fact tried a saticon a few years ago but failed i didn't know enough of what i was doing at the time .

http://www.taswegian.com/NBTV/forum/...&hilit=saticon

Re: Head amp for a vidicon
 

That's something i have not come across i was looking at this PMT head amp or pre amp ,i am fine with testing a few circuits to see what seems to work is best i was not sure how much was out there ...as i rather like image tubes and its some thing i want to master ,i have a few laying around and some more PMTs
which i manged to get up to 64 line reflection flying spot camera images shown here some tests me in there some where towards the bottom in one of the tests i think i for got the flip the images so some upside down like my son in the below one
https://www.youtube.com/watch?v=Bngl5qvgwaY
https://www.youtube.com/user/039dale...y=flying+spot+
I also like to try in the future a sstv version classic 8 seconds 120 line and perhaps a vidicon saticon version ..the are interesting things !

Re: Head amp for a vidicon
 

That is a very early camera.
The stuff I have got is a bit more modern and components were getting more affordable.
I have dug out a couple of photos from my hard drive.
There is one with the resistors laid flat to squeeze it in behind a big lens and another that has been suffering with a treatable case of blue tantitis.

They should be easy to reverse engineer if I have not already got a diagram.

Re: Head amp for a vidicon
 

The last vidicon camera I repaired used a Nuvistor as the pre-amp. I think it was about 1984.
Alan.

Re: Head amp for a vidicon
 

Attached should be the video circuit from the Mullard Educational CCTV Camera project.

Re: Head amp for a vidicon
 

I can just see a transistor more than likely a FET ,i have never seen a head amp on around the Target area like that !
Yes mines early 70s vintage for the deflection coils focus coil, the image tube i think is a bit later replacements for the early version of it .
Did you make this image tube camera ?
I would be interested in the head amp circuit if you could be bothered sketching up the circuit .
I have some newer image tubes which i also plan the turn into cameras so trying different ideas on the head amp side to see what works best .
Thanks for the photos tha's a idea i didn't think of for this camera ,i did mount a PMT head amp close to its output but didn't think of it here .

Re: Head amp for a vidicon
 

I have not heard of that one ! do you have the whole camera circuit just out of interest ? but thanks for the head amp video circuit part of it the transistor look to be easy to find a modern replacement ..this is a good one i wonder what tube it used ?

Re: Head amp for a vidicon
 

The camera I have been tinkering with was an old prototype that was given to me when the production model was discontinued.
It is like a bullet cam but more like a tank shell.

Re: Head amp for a vidicon
 

A B/W vidicon is very rare now to find here in Australia, in the early 1980's you could still get them ...then colour cameras started to come in.
I have not seen one like you have ! nice lens system on that beast !

Re: Head amp for a vidicon
 

That lens needs to be taken apart and rebuilt. The glass elements have worked loose.
I have several lenses including a fully motorized one.

Re: Head amp for a vidicon
 

I am glad other people have a interest these...not easy to get them going without schematics, was yours working from the start ?
I tried the PMT circuit for a head amp from a few posts ago it was a no goer i tested a signal in and it was 4 times the signal without this thing so that was a
waste of time i am sure its fine for a PMT but here its no good for what i need it to do.

Re: Head amp for a vidicon
 

The bits I was given were a couple of prototype units with a later circuit diagram with the head amp shown as a block. I can't remember if I have a circuit diagram for the head amp but I do have a couple of broken ones and quite a few boards that were production rejects.
The bits I am short of are lens mounting brackets and scan coils.
I have three sets of working boards with scan coils and only one good scan coil to lens mount. I could use a dead chassis with a C-mount thread on it.

Re: Head amp for a vidicon
 

Yes the scanning deflection coils are harder to find ! even on ebay tons of old image tubes but your lucky if you ever find a deflection coil for them so having a few as you do is rare .
So you have a a few bits to same model Vidicon but not working getting it to work is a satisfying challenge ~!

Re: Head amp for a vidicon
 

The mechanical parts are most likely less of a problem than getting scan coils but do come a close second for being difficult to get.

Re: Head amp for a vidicon
 

I noticed labguy has a design for he;s tiny IKE camera
http://labguysworld.com/IconoscopeCameraProject_007.htm
So i am giving this a go ,i finished it but have to add the transistors to the transistor sockets /.