Jump to content
Monk

Harmony Cart Interference

Recommended Posts

Or, if someone wants to crack open their 32-in-1 and take non-blurry pictures of both sides of the board, that might reveal something.

Share this post


Link to post
Share on other sites

Also, what make and model of television is everyone using? Just looking for patterns here - maybe certain televisions are sensitive.

Share this post


Link to post
Share on other sites

You might need to send the Harmony cart and the problem 2600 console to him to really find out what's going on.

 

I only HAVE problem consoles.. I can't afford to send them all, hehe.. but I wasn't talking about finding out what's going on, just about perhaps the possibility of creating some unofficial hack versions of Harmony Carts which wouldn't have the interference. Though you may be right - it might be impossible to create such carts if the problem isn't found first.

 

- Monk

Share this post


Link to post
Share on other sites

Also, what make and model of television is everyone using? Just looking for patterns here - maybe certain televisions are sensitive.

 

Yes, I have tried with four different televisions, and it has always been the same. (two panasonic, two philips)

 

Again the explanation-killer; why would a television be sensitive to Harmony Cart but not sensitive to original carts..

 

- Monk

Share this post


Link to post
Share on other sites

Or, if someone wants to crack open their 32-in-1 and take non-blurry pictures of both sides of the board, that might reveal something.

 

I could do that later on, I have really not much use for the 32-in-1, it doesn't have that many good games anyway. I could actually even send the whole cart to you, but I am not sure if I have your address or not - I think it might be on the envelope that you sent - could that be right? Well, I can look into it later on.. the post office isn't open until monday anyway in this country.. (I found out american post offices are open also in saturday! that's remarkable)

 

I plan to keep you informed in any case..

 

- Monk

Share this post


Link to post
Share on other sites

You might need to send the Harmony cart and the problem 2600 console to him to really find out what's going on.

 

I only HAVE problem consoles.. I can't afford to send them all, hehe..

You would only need to send one.

Though you may be right - it might be impossible to create such carts if the problem isn't found first.

Exactly.

Share this post


Link to post
Share on other sites

Again the explanation-killer; why would a television be sensitive to Harmony Cart but not sensitive to original carts.

Because the Harmony Cart is really a small computer (lots of components and circuit traces), while the original carts are very primitive (just a few components and circuit traces). Even though the game code you run via both are the same, it's the additional components and circuitry that can cause the interference. It's hard to say why your specific TV is more susceptible to it.

 

Some of the original carts have additional components & circuits which can cause interference:

  • Pitfall 2 has a co-processor known as the DPC.
  • Your 32-in-1 cart has additional chips beside the ROM which controls which of the 32 games the Atari sees when it powers up.
  • Games that are > 4K have additonal circuitry that controls what the Atari sees (it can only see 4K of the cartridge at any given time).
  • Other games have additional circuitry to handle addtional RAM.

 

near-final Harmony insides (from this blog entry)

post-3056-126301201125_thumb.jpg

 

4K board (unpopulated - it needs 2 additional chips and a capacitor):

post-3056-126301252194_thumb.jpg

Edited by SpiceWare

Share this post


Link to post
Share on other sites

I don't think *our* TVs are more sensible.

I have tested a Sony CRT and a Samsung LCD.

Monk has used two Panasonic and two Philips.

I don't know what TV zagon has used.

Perhaps *PAL* TVs tuners are more sensible?

Share this post


Link to post
Share on other sites

Perhaps *PAL* TVs tuners are more sensible?

Since they use difference frequencies all over, they have different resonance frequencies. But haven't we got reports from NTSC consoles too?

Share this post


Link to post
Share on other sites

Perhaps *PAL* TVs tuners are more sensible?

Since they use difference frequencies all over, they have different resonance frequencies. But haven't we got reports from NTSC consoles too?

Yes, but, if I am not wrong, connected to a PAL TV (capable of displaying NTSC like many European TVs).

Share this post


Link to post
Share on other sites

Just to sure:

 

1. The same cart has been tested at different TVs AND consoles and combinations of those two.

2. When switching TVs or consoles ALL components have been switched at least once (e.g. video cable, power supply etc.)?

3. There were no interference differences when doing so?

 

All three right?

Share this post


Link to post
Share on other sites

I have tested each console with its video cable and its power supply on 2 TVs.

Interferences were identical.

Moreover, I have checked Monk's video, and Pitfall's interferences are identical (in the same screen position) to mine.

 

 

Share this post


Link to post
Share on other sites

I have tested each console with its video cable and its power supply on 2 TVs.

Interferences were identical.

Then logic indicates that it is not your hardware. And since by far the most people are not complaining, it cannot be a general Harmony design problem. Which only leaves a buggy cart.

 

Moreover, I have checked Monk's video, and Pitfall's interferences are identical (in the same screen position) to mine.

Which indicates that the bug is the same. Something specific in the production process of the cart might not be 100% reliable. After you or Monk send back the cart, it guess it should be rather easy to find the problem.

 

But all that's just based on my pretty basic understanding. :)

Share this post


Link to post
Share on other sites

Or, if someone wants to crack open their 32-in-1 and take non-blurry pictures of both sides of the board, that might reveal something.

 

Mines a CX26163P copyright 1988. The ROM on board is copyright 1991 tho

 

Pictures :-

 

post-21935-126304093688_thumb.jpg

post-21935-126304105442_thumb.jpg

 

I have some more closeup shots in multiple parts. Let me know if you need them.

Share this post


Link to post
Share on other sites

After some more investigation I have detected that the arrangement of the RF-cable is important.

If I straighten the RF-cable so that it doesn't have any loops I get the same interference reduction that I got from

wrapping the cart in foil and grounding it. If I coil up the RF-cable the interference increase.

 

I will Investigate some more, I have read several suggestions in this thread I haven't tried yet.

Like putting an iron-bead on the RF-cable and checking the shielding of the RF-unit in the Atari.

 

Perhaps it is just a matter of sorting out my RF-sensitive setup.

Share this post


Link to post
Share on other sites

zagon, if when you move or bend your cable the interferences change, the problem is in your cable and not in Harmony cart.

 

In this case so far only 2 Harmony carts have this thread's problem, mine and Monk's one.

Perhaps, as I and Thomas have written,

 

In this moment the results say it is an individual problem of our four carts (now only two carts).

 

Then logic indicates that it is not your hardware. And since by far the most people are not complaining, it cannot be a general Harmony design problem. Which only leaves a buggy cart.

Share this post


Link to post
Share on other sites

It's hard to say why your specific TV is more susceptible to it.

 

You mean why my FOUR (4) specific TV's -would be- more sensitive to it (and soon to be tested a fifth one, perhaps later on a sixth one too)

 

But otherwise, your explanation is very interesting, and that could of course be the case.

 

Though I have now tested a bit more, and found a curious phenomenon; the NTSC Atari produces a bit more interference than the PAL one! At least the interference is slightly visible in Cosmic Ark original cart with the NTSC version (but not enough to bother at all), but with PAL you really have hard time finding it.

 

Some original carts, however, produce this interference too, but it looks a bit different, and is less bothersome. For example KABOOM! does this with the NTSC Atari (haven't much tested with the PAL one because that one doesn't support paddles) ..

 

It's an interesting phenomenon in any case, and there have been many good explanations here. Now, if we could devise some tests to figure the truth out once and for all..

 

- Monk

Share this post


Link to post
Share on other sites

Perhaps *PAL* TVs tuners are more sensible?

Since they use difference frequencies all over, they have different resonance frequencies. But haven't we got reports from NTSC consoles too?

Yes, but, if I am not wrong, connected to a PAL TV (capable of displaying NTSC like many European TVs).

 

Well, not exactly; my TV's can show Amiga's and Dreamcast's NTSC picture just fine. But Atari outputs some kind of different NTSC Signal (so perhaps those TV's that I have can mostly display only PAL60, and not 'true' NTSC with color and audio). Someone told me that Amiga doesn't output a 'genuine' NTSC signal (though why does Amiga's NTSC work just fine in an american NTSC monitor with colors and everything then? They wouldn't make american NTSC monitors PAL60 compatible, would they? Then they could make it as easily a PAL/NTSC monitor (which it wasn't))..

 

So perhaps an european-made Dreamcast also produces only PAL60, even if I put an NTSC game in it. (meaning only the Hz-rate is changed, but the colors are still in PAL system)

 

So, the NTSC Atari has not really been tested with fully NTSC-compatible television yet (or perhaps I would need some special cable? I don't know yet, I can only theorize so far) - only my PAL/PAL60-televisions, which produce good picture quality but in grayscale only, and without sound.

 

Otherwise you are correct.

 

- Monk

Share this post


Link to post
Share on other sites

Just to sure:

 

1. The same cart has been tested at different TVs AND consoles and combinations of those two.

2. When switching TVs or consoles ALL components have been switched at least once (e.g. video cable, power supply etc.)?

3. There were no interference differences when doing so?

 

All three right?

 

Yes, except for me I haven't had the chance to try with different PSU's, because I only have two; one for the NTSC Atari, one for the PAL Atari (and for obvious reasons, I am not gonna switch those)..

 

But I have one more PSU at my disposal later on probably, so I can test that one as well. I am pretty sure it won't make any difference though.. because again.. how could the PSU determine that only some carts are effected, but some carts are not..

 

That 'cart complexity' theory is probably the best theory so far.

 

- Monk

Share this post


Link to post
Share on other sites

That 'cart complexity' theory is probably the best theory so far.

So far, as written by me and Thomas, the only proven theory is that it's an individual problem of our two carts.

I don't know how many carts Fred has sold (in particular in Europe) but *so far* you and I are the only persons with this problem.

Share this post


Link to post
Share on other sites

That 'cart complexity' theory is probably the best theory so far.

So far, as written by me and Thomas, the only proven theory is that it's an individual problem of our two carts.

I don't know how many carts Fred has sold (in particular in Europe) but *so far* you and I are the only persons with this problem.

 

It COULD be a problem in our Atari's too, you know. Though it's starting to be a bit unlikely.

 

How about THIS for explanation?

 

http://www.nature.com/nature/journal/v440/n7087/images/440982a-i2.0.jpg

 

(just joking actually, but something to humorously consider anyway (-: )

 

- Monk

Share this post


Link to post
Share on other sites

Then logic indicates that it is not your hardware.

 

What logic indicates that? Anything is still possible, you know. I guess we'll know more when I receive the other cart..

 

But you know, a buggy Harmony Cart wouldn't explain the same interference in 32-in-1 cartridge and Kaboom! original, for example. It's still there with those carts.. although not as bad with Kaboom! original as it is with Kaboom! Harmony Cart version.

 

- Monk

Share this post


Link to post
Share on other sites

Or, if someone wants to crack open their 32-in-1 and take non-blurry pictures of both sides of the board, that might reveal something.

 

Mines a CX26163P copyright 1988. The ROM on board is copyright 1991 tho

 

Pictures :-

 

 

I have some more closeup shots in multiple parts. Let me know if you need them.

Thanks for the pictures. The Harmony does have a few things in common. The first is large capacitors. Not sure how big those are on the 32-in-1 but the Harmony has a 4.7 uF cap. The Harmony and 32-in-1 also have series diodes. I think this might have an effect if the diodes were damaged or running near their maximum ratings. They are not running near ratings on Harmony but it might be possible that they are damaged.

 

I have encountered one Harmony with a bad diode that would program but not run on the 2600. The diode was dropping around 1.7v which is way more than it should. Maybe you two have bad diodes that are dropping just enough voltage to cause problems with power regulation but not enough to cause complete failure.

Share this post


Link to post
Share on other sites

What logic indicates that? Anything is still possible, you know. I guess we'll know more when I receive the other cart..

Mine. Maybe your's is different.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...