Is My Intellivision Sick?

[bishb25]

Hi All,

 

 I picked up an Intellivision 2609A off ebay as untested with a bunch of games. Everything works, but I've noticed a few anomalies. In Donkey Kong levels 1 & 2 the center ladder is glitched. In B-17 Bomber the gunner positions have unnecessary characters displayed in the field of view, and the sky is pink making it really hard to see the enemy fighters. Some levels in Burgertime have ladders with large gaps, but you can climb them just fine. I've never had an Intellivision before and am wondering is my console damaged or are these normal glitches for these games. 

 

Thank you

[mr_me]

Light blue, which is used for sky in a few cartridges, can look pink on newer televisions.  Otherwise the bad tiles are not normal, my guess is a faulty stic chip.

[+-^CrossBow^-]

12 hours ago, mr_me said:

Light blue, which is used for sky in a few cartridges, can look pink on newer televisions.  Otherwise the bad tiles are not normal, my guess is a faulty stic chip.

Possibly but could also be a faulty Hi or Low RAM chips for the video too. But trying out a different STIC would be the first thing as that is usually in a socket (on both models) so it can quickly be swapped with another to test for this.

 

The hi | lo RAM on the other hand, is soldered directly to the boards on both models unless it has been replaced in the past.

 

[Ben_Larson]

It could be a bad STIC chip as others said.  But don't go trying to find a replacement just yet because first you'd have to get the RF shield off the board which isn't exactly simple.

 

That's because the way it's designed is fairly idiotic - the two halves of the RF shield are soldered on.

 

So you'd need a good soldering iron (i.e. 60+ watts) plus a screwdriver to pry with, or else a dremel.

 

It's a real pain.

[mr_me]

4 hours ago, -^CrossBow^- said:

Possibly but could also be a faulty Hi or Low RAM chips for the video too. But trying out a different STIC would be the first thing as that is usually in a socket (on both models) so it can quickly be swapped with another to test for this.

 

The hi | lo RAM on the other hand, is soldered directly to the boards on both models unless it has been replaced in the past.

 

Yes, first I thought the stic was doing something strange because the ladder tile is offset by less than eight pixels.  But it's not, some ladder patterns are drawn to the right others to the left.  I'm now thinking the stic is okay and would first look at the 16-bit system ram chip.

Edited December 11, 2023 by mr_me

[walldog1]

3 hours ago, mr_me said:

8 hours ago, -^CrossBow^- said:

 

Yes, first I thought the stic was doing something strange because the ladder tile is offset by less than eight pixels.  But it's not, some ladder patterns are drawn to the right others to the left.  I'm now thinking the stic is okay and would first look at the 16-bit system ram chip.

I agree. Also, some of the INTV 2609's use 8-bit system for the Hi-Lo RAM chips as you are probably aware of. I am still not aware of what determined which INTV's got the 8-bit or the 16-bit system....maybe manufacturing date???

[mr_me]

3 minutes ago, walldog1 said:

I agree. Also, some of the INTV 2609's use 8-bit system for the Hi-Lo RAM chips as you are probably aware of. I am still not aware of what determined which INTV's got the 8-bit or the 16-bit system....maybe manufacturing date???

They all have both 16-bit and 8-bit ram.  The gram is 8-bit and stores graphics patterns.  The 16-bit ram stores the background graphics attributes of the 240 background tiles.

[bishb25]

Wow, Thanks for all of the replies.

 

From what I've read the consensus appears to be bad RAM? So, am I going to have to start buying up intellivisions until I find one with good chips, or is there a source for chips I haven't found yet?

 

 

[walldog1]

2 hours ago, bishb25 said:

From what I've read the consensus appears to be bad RAM? So, am I going to have to start buying up intellivisions until I find one with good chips, or is there a source for chips I haven't found yet?

You can find these Hi-Lo RAM chips on eBay and other sources. And yes, 8-bit ram are 22 pin and marked GTE3539.  Four bit ram are 18 pin and marked AM9114. This is what I mistakenly referred to a few posts ago about 8-bit & 16-bit. Make sure to order sockets for the corresponding number of IC Chip pins as well.

 

The tracings going to these chips run in between the legs of the other RAM so be careful as you remove the solder and IC chips from the board.

[mr_me]

The 16-bit system ram is a custom IC part RA-3-9600, at location U2 on the main board.  It's socketed, so no soldering, but as others have said you'd have to get through the metal shield.

 

The graphics patterns themselves look correct so I think the gram is working.  It seems to be displaying the wrong pattern at the same locations which is why I'm suspecting the 16-bit system ram is at fault.

[+-^CrossBow^-]

5 hours ago, mr_me said:

The graphics patterns themselves look correct so I think the gram is working.  It seems to be displaying the wrong pattern at the same locations which is why I'm suspecting the 16-bit system ram is at fault.

Good point..the sprites at least look correct so that does more or less indicate the Hi Lo RAM is likely okay. So yeah, the 9600 IC would be the next in the mix at that point. 

 

the RF shielding for the model 1 isn't that bad really. What I do is use a solder sucker or my desoldering iron to suck up the bulks of the solder on each tab. After that I come back with a small flat blade screwdriver and carefully start to separate the two shields using my iron to heat up the tab and work my way around from there.

 

However, the model 1 Intellivision is one of the few consoles where I do NOT reattach all of the RF back in place. I usually keep the larger section that is black removed and only reattach the smaller silver shield.

 

 

[Sinjinhawke]

That is what I do as well.  Still a royal pain but totally manageable.  The Intellivision 2 definitely wins for accessibility.  

[HunterZero]

I agree to try swapping the RA-3-9600 system RAM chip first. That seems to be the most likely IC to fail in my experience. That is, if you can find a 2nd unit to provide the part needed for the swap, and decide to crack open the sarcophagus RF shielding!

 

Try a few more games, and see if you get any other symptoms if you can.

 

- J

Edited December 14, 2023 by HunterZero

[bishb25]

Well,

 I bought a parts console off of ebay.  It has a broken controller. I'm hoping that is the reason why it was decommissioned and not something else wrong. Here's hoping what I need from it still works.

 

As far as making the repairs, I do have basic soldering skills, tools, and have assembled & repaired my PC's & laptops before. 

 

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Try a few more games, and see if you get any other symptoms if you can.

I can't think of any other games with noticeable problems. Space Armada, Battle Tanks, Lock n Chase and others all appear to work fine. Oh, As I was typing I just remembered River Raid has graphical glitches in some spots where the water meets the land. Mouse Trap has a visible wall in the bottom right of the maze that isn't a real wall. The mouse and cats pass right through it.

[bishb25]

Good News and Bad News,

   The good news... The parts console arrived this morning. I tested it and except for the broken controllers it works perfectly. It's an older model 2609 S/N 094150. The controller with the broken shell works, but the keypad on the full controller doesn't work. If I can find a replacement shell, I think I can fix both controllers.

   The bad news... The new console works so well I don't want to tear it apart to fix the glitched one.

I guess I'll put the controllers from the glitched console into the new one and have one fully functioning console while I look for affordable parts.

Something Interesting... If I play a game that was glitched in the old console and play it in the new console, then put it back in the old console the glitches will go away for a while but will come back after extended gameplay.

 

 

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Try a few more games, and see if you get any other symptoms if you can.

I did find a sprite glitch in Frogger. The yellow cars will "drag" a yellow frog face behind them doubling the length of the cars and causing a frogpocalyps. 

[HunterZero]

Definitely just swap the intact controllers from the glitching console to the good one for now, no point tearing into a working console logic board. The controllers plug in to the edge of the logic board, so easy to swap without desoldering anything.

 

Just be VERY careful of the 5 pin ribbon power strip when lifting the logic board to replace the controllers.

 

- J

[bishb25]

On 12/20/2023 at 11:37 AM, HunterZero said:

Definitely just swap the intact controllers from the glitching console to the good one for now, no point tearing into a working console logic board. The controllers plug in to the edge of the logic board, so easy to swap without desoldering anything.

 

Just be VERY careful of the 5 pin ribbon power strip when lifting the logic board to replace the controllers.

 

- J

Yup, already done. Right now, I'm just looking for a controller and the right chips. 

[bishb25]

A generous member here sent me an RA-3-9600 chip. I replaced the one in my glitching console and so far, none of the graphical anomalies have returned. My son and I have played Burgertime, Donkey Kong, & Frogger for several hours glitch free.