Trellot

Update:  Late in coming,  but I composite modded the above Atari 2600 Vader board and now it has perfect video and audio!  Gifted the system to my brother for his birthday with a selection of great games!
~ Trellot

Yes!  Just this last weekend I finally got this system working.  I was in the market for the 1.8mH inductor but was warned away from thinking that was the issue from Best Electronics.  They mentioned I should try replaicing the the two polystyrene sound capacitors on the board which I ordered and replaced.  Didn't solve the problem.  The problem morphed from having only static and not being able to play the games to having good video and sound after performing that short.  But then on games like PacMan Ms. Pacman and Jungle Hunt, etc., the game would perform a sound glitch and freeze or in Jungle Hunt's case would start the game at the aligators but you couldn't play.  So, I then decided to try swapping out chips but they were all soldered down on the main board, sigh!   I chose to pull all the chips and socket them for ease of use in the future and it paid off since it ended up being the last chip I socketed, the RIOT chip.  Now the system plays great, although I get a little buzzing noise every once in while during gameplay.  Not sure why that's happening?  I tried adjusting the sound coil and the rf modulator and it makes a little difference but the buzzing just sort of slips in now and then.  Overall, I'm happy the results!  I'll post a pic soon of the finished product!
 
~ Trellot

Yes!  Just this last weekend I finally got this system working.  I was in the market for the 1.8mH inductor but was warned away from thinking that was the issue from Best Electronics.  They mentioned I should try replaicing the the two polystyrene sound capacitors on the board which I ordered and replaced.  Didn't solve the problem.  The problem morphed from having only static and not being able to play the games to having good video and sound after performing that short.  But then on games like PacMan Ms. Pacman and Jungle Hunt, etc., the game would perform a sound glitch and freeze or in Jungle Hunt's case would start the game at the aligators but you couldn't play.  So, I then decided to try swapping out chips but they were all soldered down on the main board, sigh!   I chose to pull all the chips and socket them for ease of use in the future and it paid off since it ended up being the last chip I socketed, the RIOT chip.  Now the system plays great, although I get a little buzzing noise every once in while during gameplay.  Not sure why that's happening?  I tried adjusting the sound coil and the rf modulator and it makes a little difference but the buzzing just sort of slips in now and then.  Overall, I'm happy the results!  I'll post a pic soon of the finished product!
 
~ Trellot

Hi all,
 
I've recently purchased a 4-swtich 2600 Vader unit but I only get static noise, no sound at all from the unit.  Great video though!  Looking for some suggestions on how to resolve this issue if possible.
 
What I've done:
 
Cleaned mainboard top and bottom with alcohol and toothbrush Dismantled and cleaned all the switchs which now work great Electrically tested voltage regulator and power jack (all well within range) Noticed rust under the RF shield and the top and bottom plates had some rust on them which I've abraided away. Tried the sound adjusting coil but got nothing from that Tuned the RF Modulator without success Noticed a rusty base on the RF modulator box so I desoldered it and cleaned it all up (rust on the board underneath which I've also cleaned well) Resoldered the RF modulator but get the same static noise Replaced the sound adjust coil with another working unit (no dice). Should there be anywhere else that I need to look other than the RF modulator?  I've read that the TIA also manages sound as well?
 
Any suggestions would be appreciated!  As it stands now all is perfect except the static noise I get.
 
Thanks,
 
Trellot
 

The ones you indicated were?
- 78F1R8K-RC-ND
- M8172-ND
 
Yes, I will send Best a note on this.  Thanks Kamakazi20012, I really appreciate your time!
 
Regards,
 
~ Trellot

The ones you indicated were?
- 78F1R8K-RC-ND
- M8172-ND
 
Yes, I will send Best a note on this.  Thanks Kamakazi20012, I really appreciate your time!
 
Regards,
 
~ Trellot

Hi all,
 
I've recently purchased a 4-swtich 2600 Vader unit but I only get static noise, no sound at all from the unit.  Great video though!  Looking for some suggestions on how to resolve this issue if possible.
 
What I've done:
 
Cleaned mainboard top and bottom with alcohol and toothbrush Dismantled and cleaned all the switchs which now work great Electrically tested voltage regulator and power jack (all well within range) Noticed rust under the RF shield and the top and bottom plates had some rust on them which I've abraided away. Tried the sound adjusting coil but got nothing from that Tuned the RF Modulator without success Noticed a rusty base on the RF modulator box so I desoldered it and cleaned it all up (rust on the board underneath which I've also cleaned well) Resoldered the RF modulator but get the same static noise Replaced the sound adjust coil with another working unit (no dice). Should there be anywhere else that I need to look other than the RF modulator?  I've read that the TIA also manages sound as well?
 
Any suggestions would be appreciated!  As it stands now all is perfect except the static noise I get.
 
Thanks,
 
Trellot
 

Hi All,
 
I'm back at troubleshooting this Atari issue.  I ordered a few replacement parts from Console5:
7805 +5v Voltage Regulator 3-Pin TO-220 MC7805ACTG 5v 2200uF 16v Axial Nichicon VX Electrolytic Capacitor Atari 2600 VCS DC Power Jack NOTE: I was testing the Atari mainboard/switchboard with a game installed and power applied to simulate a full load to the system, then I remeasured the same points above.  Here's what I got:
Voltage regulator IN = 7.58v Voltage regulator OUT = 4.72v Power jack = 7.82v I also measured reset Pin-1 on the Micro Processor chip (R6507) and got 4.71v Once I get the parts I will start with the voltage regulator then go on from there.  But from the numbers above, would anyone know if this should be enough power to boot the board?  Crossbow above mentioned that his board wouldn't power on under anything in the 7v range unless he started high then lowered it.  Also, some material I've consulted suggests that the numbers are too low, below the 1/10th of a volt spread +/-, at least in the case of the VR IC.  I'll update again when I've swapped out the VR.  Should be a few days to a week before I get them due to the Easter break.
 
Thanks,
 
Trellot

Thanks rickr for your help on the pics, that was easy!

Alright fellas now I'm getting somewhere.  I replaced the 7805 voltage regulator and I'm getting 10-11 volts IN and 5 volts out under a full load.  The power jack also reads 10+ volts under a full load.  What I get now is a completely solid black screen.  Should I check the graphics chip for this?
 
Thanks,
 
Trellot

Hi all,

 

ISSUE: I have an old Atari 2600 REVB board, for the six-switch console, which outputs nothing, when powered on, to my mid-1990s Panasoncic Omnivision TV/VHS unit.  If I move the main board + switch-board around, while powered on, every so often the screen turns from the channel 2 or 3 solid blue look to a black screen with some buzzing noise from the speakers.  

 

Below are the debug steps I have taken thus far:

Thoroughly cleaned the main board really well to begin.  (there was some corrosion near the base of the 12-wire harness connections)
Pulled all socketed IC chips from the non-working board and tested them in a known good working unit and found that they all work fine (8021E, R6507, R6532). 
Electrically tested the UA78M05 voltage regulator on the switch board with power plugged in and the power switch turned On: (IN = 7.8volts; OUT = just over 5 volts). NOTE: This switch board works on my known good Atari board but with bad washed out colors; only Black and White seems clear on certain games. 
Electrically tested the power adapter on the main board with power On: (both power points read around 8.10 volts). 
Desoldered the 12-pin wire harness from the board and cleaned up the through-hole area really wetll, then ran continuity on all 12 wires which was good. 
Soldered the harness back on and checked continuity again which was good. 
Re-flowed solder on the on-board power adapter as well; got the same voltage readings of around 8.10 volts. 
Ran continuity checks on a lot of the traces on the back of the board and everything I checked seemed good.  (NOTE: I'm a Noob so this mean nothing  )  
Observation: when power is applied to the board I can feel the chips getting slightly warm so they appear to be getting power.
I'm using the same 9volt AC Adapter on the non-working Atari as on the working Atari.
 

At this point I'm not sure what to check.  I've thought about replacing the voltage regulator and the 2200 UF-16V big cap on the switch board but this switch board basically works on my known good Atari board which makes me think the issue is with the main board.  Any suggestions from the community would be greatly appreciated.

 

Thanks in advance,

 

Trellot