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Making a Camcorder Viewfinder Work

I've got a viewfinder from a broken old camcorder, and am trying to figure the pinout for it. The camera itself actually works, so I can power it up and measure things, but I have no oscilloscope.

There are 5 conductors, 2 of which are power. I'm pretty sure that one is horizontal sync, because I get the classic pattern of ~30 degree sloped lines moving slowly down the screen if I connect 2 conductors (I can't recall which just now) to a standard NTSC signal. I also get a fleeting distorted image for a couple of seconds before the pattern settles in.

What's the minimum equipment I'm likely to need to figure out what is coming out of each conductor from the camera? Also, does anyone know what I'd need to strip out the horizontal sync from an NTSC signal and put it on a separate conductor? Something cheap, small and not power hungry would be good, because I'm trying to use it as a poor man's head mounted display.

If it's any help, the viewfinder is from a very old Magnavox Easycam 8.

Ewan

Reply to
Captain Blammo
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Hmm, don't know muuch about Magnavox but my service manual for a Sony CCD-TR78, 88, 98, 99, 514, 590, 614, 714 814 shows a 5 conductor flex going to the viewfinder board VF-102 as 1- 5V, 2- GND, 3- Video, 4- tally, 5- NC. a lot of these are very simular. Hope that helps

Richard

Reply to
Richard

Hey Ewan, Took a quick look at another Sony I have in pieces. It has a 4 conductor cable going to the viewfinder. It follows the same layout as above and yes pin 5 is No Connection. In this case just not there. Pin

4 is Tally which actually is a video term for the little light that comes on when the camera is recording. (In a studio it's the little light on the top of the camera so the talent knows which camera to look at. It can also be turned off ) I put 5 volts from 1 to 2 (neg) and got the CRT to light up. If you open up the viewfinder you can find which pin goes to the LED that would be 4. I just use wires out of a Cat5 cable and shove them into the connector for testing. You could find one of the mating blocks (male) off some salvaged board (like junked VCR) and just cut out 4 pins mod it and plug it into this cable then you could solder your own cable up. Oh everything in this camera is NTSC EIA . Maybe I can play with it more tomorrow. Richard
Reply to
Richard

Funny you should mention it, I actually have a viewfinder from a Sony CCD-TRV22 as well, but it only has the four conductors going into the VF-102 board (Nothing on pin 5). Do you happen to know if scraping the surface off those cables is a good way to get at the conductors? I don't have the right connector to plug the end of the cable into. Also, does your manual mention what video format the viewfinder takes?

Secondarily, and please do pardon my ignorance here, I'm not well versed in the art of pinout parlay. What does "tally" mean? I assume that "NC" means "Not Connected".

Thanks for the info!

Ewan

Reply to
Captain Blammo

Maybe I can play with it

OK Ewan played with it a little this morning. Applying a standard line out video signal to Pin 3, OOhhh little tiny TV! but where's the sound? So that works as I thought 'cause I'd played with these before.

Richard

Reply to
Richard

Aha, well, I now seem to have the complete set of info for making it work. Thanks hugely, I'll try jamming some Cat5 wires in there and seeing if it works.

By the way, shouldn't the other conductor from the video cable be connected to something? Should I tie it to GND, perhaps? Either way, as long as it works, I'm happy.

Cheers!

Ewan

Reply to
Captain Blammo

Ewan, Hope this dosen't get posted twice. I posted last night but it hasn't shown up 18 hrs later. Yes that's right the ground is shared by everything. Use the solid wire as a temp thing and scab another connector to make a permanent connection.

Richard

Reply to
Richard

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