Advice on H6er Performance Issue Please

[BlimpPixel]

I have a heavy sixer (with M suffix) that I got just a couple months ago. I haven't used it much but it worked and looked really well when I did. Yesterday I had it on and things seemed to go wrong. The colors started changing, the image "vibrated", and sometimes it would just go wrong altogether and I'd just have ugly bars across the screen. It acted the same with different cartridges, and as far as I could tell letting it sit to "cool down" didn't change things.

 

I don't know if the issue is a complete mystery or if there's a most likely scenario that you guys can suggest. I'm hoping it will be the latter. I have a little experience with electronics; probably enough to fix what I'm told to fix but not necessarily enough to identify the issue myself.

 

Any help would be greatly appreciated! Thanks!

[zylon]

I would check for cracked solder joints at the voltage regulator, possibly replace it if the joints are good.

[BlimpPixel]

I have reheated up the solder joints on the regulator and cleaned up a few things, but no difference.

 

In addition to this one, I have another H6 that doesn't work at all. I checked that out, too.

 

At the regulator, I'm getting the following readings:

 

Wonky one: Pin 1 = 11.09v, Pin 3 = 4.88v, Pin 2 confirmed ground

 

Black screen one: Pin 1 = 11.88v, Pin 3 = 5.05v, Pin 2 confirmed ground

 

I'm not sure that either of these are too out of line. Thoughts, please? Many thanks!

[zylon]

The black screen one's readings are on the high side, possibly failed. Try re-seating the chips or swapping ones from the wonky one and see. You could also try swapping the switchboards between units to determine where the issue is.

[Hannacek]

I had a color problem on my heavy sixer. I replaced the 7805 regulator, and now it works perfectly. Just be careful because I lifted part of one of the pad on the pcb. It was only a small area, so I globbed on some extra solder to make a good connection.

 

 

If your chips are socketed, its a good idea to remove the chips, and make sure there are no problems. I like to clean the legs with a pencil eraser before I put them back.

Edited March 6, 2016 by Hannacek

[BlimpPixel]

It's not a great strategy, but I had some free time and wanted to brush up on my soldering skills so I went ahead and swapped voltage regulators between the two units. I was expecting their symptoms to be the same only reversed, but to my surprise, the black screen console still gives a black screen, whereas the wonky one seems to work great. I haven't had it on for too long to see if it will heat up, but either way I can at least say it's regulator-related.

 

I may order this "tune up kit" for both and just install all the components. Any other ideas? I haven't reset the chip yet as suggested. Not sure where it is but I'll investigate.

 

http://www.ebay.com/itm/Atari-2600-CX2600-6-SWITCH-TUNE-UP-PARTS-Voltage-Regulator-1-Amp-CAPACITORS-/311555817299?hash=item488a2c7f53:g:VfsAAOSwll1WxHyV

 

Thanks.

Edited March 8, 2016 by BlimpPixel

[zylon]

I'd also guess the TIA in the black screen deck has died. Swapping IC's can show if this happened.

[+DrVenkman]

I haven't reset the chip yet as suggested. Not sure where it is but I'll investigate.

 

 

I'd also guess the TIA in the black screen deck has died. Swapping IC's can show if this happened.

 

 

To elaborate a bit on zylon's post, the TIA is the 40-pin chip that is closest to the front of the main PCB. The other 40-pin chip, the one closest to the cartridge connector, is the 6532 RIOT (RAM, I/O, Timer) chip. The 24-pin chip in between is the 6507 microprocessor (basically, a little brother of the more commonly-known 6502).

[BlimpPixel]

I had it all apart for a good look. This is delving deeper into electronics than I've been before, so before I went prodding at anything I wanted to ask. Are the chips soldered onto the circuit board from the bottom or do they snap onto the bases they're sitting on (which is kind of what it looks like, but I'm not sure)? If the latter, are they just carefully removed with a little leverage?

 

Same question about the cable. I'd like to swap boards with the other console and see what that yields but didn't want to mess with the cable before I knew for certain how it disconnects.

 

Thanks again!

[+-^CrossBow^-]

Okay, the black screen one...try changing out the RIOT chip first. It is the one directly below the cartridge port and stands for Ram, Input/Ouput, Timing. Long story short if the RIOT is bad, then nothing else can initialize and it will cause the solid black screen condition. The changing colors you spoke of can be caused by a faulty voltage regulator but is also the result of a faulty TIA. As was said before, the first large chip below the cart port is the 6532 RIOT chip. The small one below that is the 6507 CPU, and the bottom larger chip is the TIA. While the TIA is responsible for the overall graphics generator in the Atari 2600, it is the RIOT that kick starts everything to the CPU. So you might give that a shot in swapping out.

 

And yes, the chips are simply pressed into the socket (bases as you called them). Use a small flat blade screwdriver to place into the small slit between the chip and the socket it attaches to on one side and twist gently to begin prying the chip loose. Do this little by little on each side until it comes free. Just be careful to not bend and break any of the pin legs off the chips in the process.

Edited March 8, 2016 by -^Cro§Bow^-

[BlimpPixel]

Thanks! And the cable? Does the white plastic end simply pry off as well?

[BlimpPixel]

Another update.

 

I took a look at the cable and decided it just pulls out, so I said a prayer and found I was correct. With the switch boards swapped I had the same results. Wonky console was back to being wonky on account of the previously swapped VR, but the dead unit was still dead. So I took it all apart again and pulled the chips as instructed, blew out the sockets with some compressed air, put it all back together, and it works great! I really didn't have high hopes, I'll admit, but that shows what I know. So we're in business at last, although I still need to order the tune up kit for at least one, but perhaps both just for the heck of it.

 

I really appreciate all your input! Couldn't have done it without you guys.

 

BTW, is contact cleaner safe to use on these systems? I don't see why it shouldn't be, but I wanted to ask.

[OptimusMaximus]

Does anyone here know how to purchase these chips? Best Electronics said he sells them in tubes? not by the each? And ebay... Anywhere else?????

thanks....

[BlimpPixel]

Hmm I've purchased them individually from Best. Either things have changed or there was some miscommunication.