Slightly OT? 1701 Monitor question

[BBQedIguana]

I posted this question on the TPUG list, and I thought I'd put it here as well to see if you guys had any ideas. Not sure if this goes in Hardware or Other Systems, since it's about a 1701 and not a VIC specifically. ANYWAYS...

I was lucky enough today to find a 1701 monitor for free on Kijiji. Once I got it home, I tested it. The chroma/luma/audio jacks on the back work fine, but the video/audio jacks on the front don't. Since my VIC-20 would use those, it prompted me to open up the monitor. There's a tiny circuit board that holds the video and audio jacks, and that board appears to have rotted and cracked - a corner is completely missing, and several of the traces have broken. I can get audio to work if I wiggle the jack around a bit - only 1 of it's 3 traces are broken. But the video has 2 of it's 3 traces broken, and part of the board to boot!

Does anyone know if parts for 1701's can be purchased somewhere? Even if it cost me a few bucks, it would be worth it to save this monitor. Everything else about it works fine - the case is a bit scratched up, but functionally, this is the only problem I could find. There are some numbers on the circuit board in question:

JVCS75V0
CK10166-B01 (6/6)

Doing some Googling turned up nothing but VCR parts. I'm just wondering if anyone here knows a bit more about the 1701 than I do (likely!). In the end, I may just have to find a Commodore 64 to use with it.

Thanks!

Rick Towns
Barrie, Ontario, CANADA

[carlsson]

You could also do the S-Video modification to your VIC-20.

It seems the US company AG Tannenbaum think they can find you a 1701/02 service manual for $24. If it exists, perhaps someone already scanned it although I did not see anything on Zimmers FTP.

http://www.agtannenbaum.com/c_cat.html#COMMODORE

Look inside the monitor for other markings. From what I understand, all Commodore monitors are more or less rebranded. If you find evidence this 1701 is known under a different name, there is a small chance you could find information about the other model.

Someone might even have a working monitor to open and take pictures of. I suppose it might be one of your best options.

[BBQedIguana]

I've actually go my VIC working on a Sylvania TV using the proper A/V cables for the VIC - it's WAAAAAAAAAAAAAAAAY better than the old RF converter box I used as a kid. The picture is so nice! I might do the S-Video conversion at some point, but right now I don't even have an S-Video TV to hook it up to! LOL!

The 1701 is just for fun. If I can get it working, great. Otherwise it's worth what I paid for it (nothing!). If I can get it running with the VIC, I think a new paint job is in order... a VIC 1701 anyone? LOL!

[carlsson]

Luma + Chroma ~= S-Video, so you actually already have a display.

If you don't need it, before you paint it you could see if there is another user (group) in your neighbourhood who wants to have it. Those tend to be rather collectable. A few weeks ago I sold a 1702 for ~$75 which however may be a bit of an inflated price.

[6502dude]

The chroma/luma/audio jacks on the back work fine, but the video/audio jacks on the front don't. Since my VIC-20 would use those, it prompted me to open up the monitor. There's a tiny circuit board that holds the video and audio jacks, and that board appears to have rotted and cracked - a corner is completely missing, and several of the traces have broken. I can get audio to work if I wiggle the jack around a bit - only 1 of it's 3 traces are broken. But the video has 2 of it's 3 traces broken, and part of the board to boot!

If the board is physically secure enough so that jacks do not woggle when you push RCA plugs into them, then why not solder 22awg wire from point where you can pick up signal - to the jack (bypassing broken traces on PCB).

It may not be pretty as a repair, but it is simple to do and the results will not be visable when case is put back on.

[BBQedIguana]

That is exactly what I was thinking of doing! (Minus the 22awg wire specification - I'm no that smart! LOL!). But it turns out I might have a line on another broken 1701/02 monitor, and I may be able to combine the two!

As for preserving this one - nobody is going to want it. It's in very rough shape, case wise. I'd rate it about a 3/10. So painting it would actually be an improvement!

[BBQedIguana]

UPDATE: I found a guy on the TPUG e-mail list who had a 1702 he didn't want (blown picture tube) and I picked it up off him today. I had a closer look at my first monitor - it's a 1702 as well! DOH! Anyway, I opened his broken one and it had a pristine sub board that I needed for the A/V connectors. I transferred it into my monitor and wired everything up. I hooked it up to my VIC and got a picture - pretty sharp but there's some really bad colour issues...



Any suggestions? I played with all the knobs on the front, plus the 5 pots in the back (with back cover off) - that crazy rainbow display doesn't change. I wiggled the wires and various boards in the back (while being very respectful of all capacitors and metal surfaces!) and it never waivered or flinched. I'm thinking maybe it's the picture tube, or an issue with the "technical" business at the back end of the tube (stuff I have no clue about!). Anyway, if anyone knows what this issue is and if there's an easy solution, I'd be very appreciative! Thanks!

Rick Towns
Barrie, Ontario, CANADA

[gklinger]

Any suggestions?

Put on some Pink Floyd and enjoy the psychedelic colours.

[BBQedIguana]

Put on some Pink Floyd and enjoy the psychedelic colours.

LOL! Good advice there! Oddly, Omega Race looks just fine on it. Hehehehehe!

[6502dude]

I can't recall if 1702 has a degaussing coil around CRT.

However, degaussing is what is needed to clear rainbow problem.

If you have a bulk tape eraser handly, this can be used (or a hand held degaussing coil).

[BBQedIguana]

However, degaussing is what is needed to clear rainbow problem.

Ah, sweet! I used to have an old Dell 22 inch CRT that had a Degauss button right in it. Unfortunately, all I have is LCD's at home now (thought maybe I could degauss the CRT with the 1702 right beside it and get a 2 for 1 sale? LOL).

I'll check around and see if any of my techie friends have a degauss coil - I don't have a magnetic media wiper - no real need with all the optical media in use these days.

Thanks for the info, though! Hopefully that does the trick.

[English Invader]

How do tape games fare on your multi-colour VIC screen?

[6502dude]

maybe I could degauss the CRT with the 1702 right beside it

If you place crt faces very close together and then turn on the Dell monitor, then this may be enough to cure problem. The 1701 does not need to be powered on when you do this.
I think I have used this trick before for a monitor that did not have a built in degaussing coil.

[Mike]

Hi, Rick,

Any suggestions? I played with all the knobs on the front, plus the 5 pots in the back (with back cover off) - that crazy rainbow display doesn't change. I wiggled the wires and various boards in the back (while being very respectful of all capacitors and metal surfaces!) [...]

The voltages used in a CRT are in excess of 25 kV, and can cause an arc - and electric shock - without you even touching any metallic parts! It already suffices to come near a high voltage part. From a metallic tip at 25 kV, an arc easily bridges 25 cm to earth potential. What you did was extremely dangerous!

Service personell uses special equipment should it be necessary to test a CRT while it's on: earthed workplaces, isolating tools and probes.

Michael

[BBQedIguana]

If you place crt faces very close together and then turn on the Dell monitor, then this may be enough to cure problem.

Sweet advice! I don't have the Dell anymore, but we've got an NEC CRT in the basement - bet it's got one! I'll try that this weekend. Thanks!