Magnavox Odyssey Repair

[lgallair]

I'm trying to fix an original Magnavox Odyssey from 1972 that momentarily flips between static, black screen and garbled noise. Luckily I have a working unit to swap modules with. I identified the faulty module to be the "Horizontal Sync Generator". So, thinking it might be the two capacitors that are dried up, I replaced them with new ones of the same specs. This did not correct the problem. I performed continuity tests between the working and non-working modules and identified (what I think) is the faulty component. According to the schematic, the component is the inductor. The specs according to the schematic is 620uh. I measured the resistence and it's 15ohms. I looked up this component on mouser.com and digikey.com but could only locate a similar one on mouser (542-9220-18-RC). My question is, is this the correct part? It looks very different from what's on the module. But I'm thinking it's because the one on the magnavox odyssey is 40 years old and that's how they made them back then. Any help you have would be very helpful in getting this piece of gaming history back to working condition.

[Osgeld]

inductor is just a coil of wire and its not going to have much resistance, its not my first suspect, it appears just to remove noise coming in on the power lines in combination with the decoupling caps on either side of it, if q2 and q3 are getting power on the emitter (q2) or collector (q3) then there is probably nothing wrong with the inductor

 

as far as your question goes, yes that should work, it can handle 88ma and although I dont know how much current that module consumes I cant imagine it to be that much. And you are correct about age vs package, that thing is honest to god hand wrapped coil of wire on a core, glued to a phenolic board, then epoxy dipped... ah the good ole days ( you will see this, even today its not THAT uncommon, but they are nice enough to put it in a plastic box to make it look tidy)

Edited November 27, 2014 by Osgeld

[lgallair]

When I test the two leads of the inductor coil on the module that works, I get continuity. But on the bad module I don't. I soldered all the leads in case of cold joints but still nothing. I'll test for power at q2 and q3.

[Osgeld]

oh ok if your not getting a reading or voltage then yea something burned it up, I didnt quite catch that, I thought you said both measured 15 ohms but Im pickin up what your laying down now

 

if its blown get a few just incase it was not a freak accident and the cause is still lingering, you will rather spend an extra 1.30 and not need it than spend another 3 bucks on postage and wait an additional 3-5 days when you do lol

Edited November 27, 2014 by Osgeld

[lgallair]

Ok, I replaced the inductor with a new one and that fixed the horizontal sync module. What I get on the screen are the squares for player 1 and 2, the wall and the ball. Both players are working fine as I can move them up/down left/right. The wall can also be moved with the dial. the ball however, is acting strange. When you press the player 2 button it releases the ball because you can see it floating across the screen, but as soon as you release the button, it "studders" back and forth. It also goes right through player 1 and 2 ... No collision is detected. Any ideas as to what to check for? All modules from bad console work in good console. All modules from good console work in bad console but with same ball behaviour. Looks like a problem with the motherboard??.

[icemanxp300]

Care to help me? I'm a noob to this stuff as well. Just got one and all I get is a fuzzy black picture w/a white dot that I can move around.

[AtariBrian]

Care to help me? I'm a noob to this stuff as well. Just got one and all I get is a fuzzy black picture w/a white dot that I can move around.

Hi Ice , who's the best pilot ? Ice , why on earth did you pick up a Odyssey ?

[icemanxp300]

https://rochester.craigslist.org/vgm/4819822545.html

 

I nabbed this for $100 and it came with an enterprex Apollo 2001 as well.

 

I can easily double, triple, my investment if I decide to sell it.

 

edit: it's not what I was going for. I went for a $20 donkey kong 2 game and watch and ended up spending $180

Edited December 27, 2014 by icemanxp300

[lgallair]

I narrowed the problem with my odyssey to the cartridge connector. It appears not all pins were making a connection which caused the erratic ball behaviour. So I resoldered all the pins and voila, another odyssey saved from destruction.

[Uppy]

Glad you could save the odyssey! For future reference and a few members might not like me for posting this you can trade or sell trashed odyssey systems to Dick on ebay. His repair man uses trashed parts to restore odysseys. Ive unfortunately had to send him a couple of odysseys that where beyond repair but hopefully they helped for restoring a few systems.

[Glen's Retro Show]

Sorry to jump in. Is there any way to fine tune the video signal to newer TVs my Odyssey worked ok on one Magnavox TV I had that broke my symphonic TV shows the picture a little bit scrambled being a digital tuner there's no way to fine tune the oddities composite output on channel three or four if I open the Odyssey is there any part that can be adjusted and one of these boards that sinking of the video? basically I'm trying to fine tune the signal before it gets to the TV vs the older TV sets that had the fine tuning on them thanks if anyone has any suggestions and thanks to anyone who doesn't too :-)