Intellivision III Help

[Gabe8273]

Hello all, this is my first post here!
This morning I bought an Intellivision III and a Colecovision (no controllers or cables for the Colecovision) for 40 dollars.

I hooked up my Intellivision and inserted a cartridge, and I'm only getting a black screen on startup. I opened it up and found out the reset button was stuck down and that a mouse chewed through the player 1 controller wires, which I fixed. Still a black screen. The light comes on, and one time I got a pink screen when using my copy of Frog Bog. I have tried alcohol and electric cleaner to no avail. Any ideas on how to fix it?

[mr_me]

You can start by checking the voltages coming to the mainboard.  Some guides can be found at the link below.  The INTV System III should be the same layout as a Mattel 2609, if yours isn't let us know.

 

https://console5.com/wiki/Intellivision

 

 

 

Edited September 6, 2022 by mr_me

[walldog1]

17 hours ago, mr_me said:

You can start by checking the voltages coming to the mainboard

Yes, it is always good to start with the basics. Poor power, poor performance.

19 hours ago, Gabe8273 said:

Still a black screen. The light comes on, and one time I got a pink screen when using my copy of Frog Bog

I have run into this quite a few times. It is usually one of the 3 heat-sinked IC Chips. STIC chip would be 1st to check on my list, followed by 9600 System RAM chip. Occasionally, the CPU chip has caused similar problems. But with a 47 year old PC Board, I have seen all kinds of things mimic a bad chip. Bad solder joints are sometimes the cause as well. As for the mouse problems, that makes me think about checking all wiring very closely for any other tiny bites that might cause a problem.

 

As an ASE Certified auto tech of 25 years, mice have made me a richer man. The wire manufacturers use a vegetable oil in the making of the the wire outer sheath. And they also love that warm engine when you get home and park it during cold weather. Then they need materials for their nest, so more car parts damage.

19 hours ago, Gabe8273 said:

Any ideas on how to fix it?

How is your DC electrical theory knowledge? Can you read electrical schematics? Do you have a good DVOM, frequency counter or a DSO? mr_me gave you a good website for most everything electronic at Console5. Or just go to the Wiki site directly as Console 5 is just directing you there.

 

I would be 90% sure of a bad Chip as I stated above. But some boards have been a true adventure to get working, so.......... good luck!

[+-^CrossBow^-]

I just had this happen with one I bought as not working for parts only and after checking the voltages on the power board and everything there checking out. Replacing the 3906 Transistors near the CPU made it fire right back up again and is one of the components I replace out anyway on any sent to me for servicing.

 

 

[mthompson]

Replacing those two transistors fixed my Intellivision that had a black screen. I detailed my troubleshooting here: 

 

[walldog1]

54 minutes ago, -^CrossBow^- said:

I just had this happen with one I bought as not working for parts only and after checking the voltages on the power board and everything there checking out. Replacing the 3906 Transistors near the CPU made it fire right back up again and is one of the components I replace out anyway on any sent to me for servicing.

 

 

Gabe8273 also mentioned getting a pink screen once or twice. So I would lean toward the STIC chip, but definitely check out those 2 3906 transistors while in there as well as the three 10qF Caps and the 47qF Cap if needed. Common failure parts!!!!! But previous owner may have changed them already in a attempt to fix. I always test and measure transistors and caps for performance before condemning them.

[+-^CrossBow^-]

3 minutes ago, walldog1 said:

Gabe8273 also mentioned getting a pink screen once or twice. So I would lean toward the STIC chip, but definitely check out those 2 3906 transistors while in there as well as the three 10qF Caps and the 47qF Cap if needed. Common failure parts!!!!! But previous owner may have changed them already in a attempt to fix. I always test and measure transistors and caps for performance before condemning them.

Makes sense...but as they are cheap parts and I'm already in there, I change it out anyway to be sure as a preventive measure. I'm really looking to see about ordering some small sinks for the TO-92 package as I know they exist but not sure how much good it would actually do. I know you have installed small fans to help with cooling them on systems you have serviced and refurbished?

[walldog1]

2 hours ago, -^CrossBow^- said:

Makes sense...but as they are cheap parts and I'm already in there, I change it out anyway to be sure as a preventive measure.

There are different quality grades of these 3906's as we once discussed before. That is why I measure. A few times the 3906's in there were much better based on their HfE readings. I think it was Console5 that was selling very poor 3906's. Their new ones measured close to what I consider the cut-off point and consider them bad. So I went to eBay and found a different brand and they had a much higher reading.

 

New isn't always better sometimes. 25 years as an automotive tech taught me that!

[walldog1]

2 hours ago, -^CrossBow^- said:

I'm really looking to see about ordering some small sinks for the TO-92 package as I know they exist but not sure how much good it would actually do. I know you have installed small fans to help with cooling them on systems you have serviced and refurbished?

Yes, the fans definitely help out. The Logic Board is actually poorly designed for heat dissipation as it mounts upside down in the case. The heat sinks on the 3 chips actually don't help much either as heat always rises and the heatsinks are under the IC Chips when installed.

[+-^CrossBow^-]

I actually ordered some 2907A from Mouser and have been using those for at least the past year.

 

18 minutes ago, walldog1 said:

Yes, the fans definitely help out. The Logic Board is actually poorly designed for heat dissipation as it mounts upside down in the case. The heat sinks on the 3 chips actually don't help much either as heat always rises and the heatsinks are under the IC Chips when installed.

And nearly completely enclosed in a metal box that doesn't offer much in the way of proper venting/cooling through convection either. I've noticed the chips on the Intellivision 2 don't have heatsinks on them and also don't seem to get as hot. I wonder if they were using TTL on the originals and CMOS based on the newer? I also find it odd they were able to make the Intellivision II without any RF shielding on them. The NES, SMS, and even the Genesis all have complete RF shielding and came after the model 2 Intellivision. So I do wonder how the FCC let that go?

 

[walldog1]

24 minutes ago, -^CrossBow^- said:

I've noticed the chips on the Intellivision 2 don't have heatsinks on them and also don't seem to get as hot. I wonder if they were using TTL on the originals and CMOS based on the newer? I also find it odd they were able to make the Intellivision II without any RF shielding on them.

Interesting about the heat difference for the Chips..... It could be what you suggested or the fact they designed a better DC power supply. The LB is also better laid out and has fuses. I figured on the INTV I that they were using a lot more diodes & Zener diodes than on vs II. To me that looks like their safety system for current/voltage overloads in 1978 - 1981 for INTV I.

 

I have also read the heat specs for the 3906 transistor as even brand new ones get too hot to touch for long, even without playing a game and an open case. The new transistors read 225^oF (from memory) and the top temp operating range was maybe 265^o? But that temp was taking while idle. Add the case, increased load from playing a cartridge and I bet it gets pretty close to the Max temp range.

 

As for the RF shielding, I am pretty sure it was for protecting the logic board from interference, not to meet FFA rules. On the INTV I, if I tune in the picture and audio on a RF Mod without a case soldered on, then put on the case, I sometimes lose the desired settings I had previously set on that RF Mod.

[Gabe8273]

Oh man, I forgot that I made this topic. 

Quote

How is your DC electrical theory knowledge? Can you read electrical schematics? Do you have a good DVOM, frequency counter or a DSO? mr_me gave you a good website for most everything electronic at Console5. Or just go to the Wiki site directly as Console 5 is just directing you there.

I don't have much experience with that stuff, I'm just a 15-year-old retro game collector. Maybe my dad and I could open it up again and check the voltages.

[mr_me]

Checking voltages isn't a big deal.  The hard part after that is getting the metal shield off of the main board so you can inspect it.  Also, be careful with the flat cable feeding power to the main board, it can be delicate.

[SiberianSpForces]

On 9/6/2022 at 4:03 PM, mthompson said:

Replacing those two transistors fixed my Intellivision that had a black screen. I detailed my troubleshooting here: 

 

Our original Intelli black screens, so this is worth a shot. 

[walldog1]

On 9/19/2022 at 2:29 PM, Gabe8273 said:

Oh man, I forgot that I made this topic.

Being new to AA, click follow this topic and you will get an e-mail reminder every time someone adds a comment. I did not know that either when I first joined. FYI.

[walldog1]

On 9/20/2022 at 9:19 AM, mr_me said:

Also, be careful with the flat cable feeding power to the main board, it can be delicate

I agree! If cable looks in good condition yet, I always wrap some scotch tape or other tape of your choice around the ribbon portion to keep it from separating. When I repair the solder joints on both side of the Logic board during a overhaul, I then add a bead of hot glue gun to underside of ribbon at the PCB for support from flexing.

[+-^CrossBow^-]

20 hours ago, walldog1 said:

I agree! If cable looks in good condition yet, I always wrap some scotch tape or other tape of your choice around the ribbon portion to keep it from separating. When I repair the solder joints on both side of the Logic board during a overhaul, I then add a bead of hot glue gun to underside of ribbon at the PCB for support from flexing.

My local electronics store actually has these flat ribbon power cables. Now, they are 6 conductor vs the 5 needed, but it cuts easily. Even though they are new, after a few bends back and forth, even they can start to separate. I sometimes will wrap kapton tape around them at the base where they are soldered to the board like @walldog1 stated as it helps strengthen that part of the ribbon cable and help prevent separation of the layers.

 

[Walter Ives]

On 9/6/2022 at 4:13 PM, -^CrossBow^- said:

I also find it odd they were able to make the Intellivision II without any RF shielding on them. The NES, SMS, and even the Genesis all have complete RF shielding and came after the model 2 Intellivision. So I do wonder how the FCC let that go?

The FCC radiation specifications applicable to the original Intellivision were very tight, because before video games and home computers nobody cared and the FCC erred on the side of caution in adopting them. When video games and home computers came out the manufacturers asked the FCC to review the standard. The FCC's job is to enable technology, and adapting its standards to the changing world is part of that charter. By the time the Intellivision II came out the standard had been revised and the new configuration was able to meet it without the full shield. The Intellivision II was actually not completely without shielding: the RF circuitry in the Astec modulator is fully encased.

Furthermore, the GI chip set was on the slower side and its signal level transitions were not particularly sharp, so they generated fewer harmonics. The later consoles you list used substantially higher-speed logic, faster clocks and may not have used a separately encased modulator.

 

On 9/6/2022 at 3:55 PM, walldog1 said:

The heat sinks on the 3 chips actually don't help much either as heat always rises and the heatsinks are under the IC Chips when installed.

To the contrary, they help a lot. Heat doesn't travel very well through plastic. By epoxying metal heat sinks onto the plastic packages the heat from the die only has to travel a short distance through plastic to reach that part of the heat sink right above the die, which then conductively distributes it efficiently across its whole area. Most of the heat leaving the heat sink is radiative (σT⁴) and the little photons carrying it don't know up from down and so go whichever way they d*mn well please. Within the tight quarters of the shield, heat transferred to air molecules hitting the heat sink dissipates by thermal diffusion, which also operates equally well in all directions.

 

On 9/6/2022 at 6:01 PM, walldog1 said:

As for the RF shielding, I am pretty sure it was for protecting the logic board from interference, not to meet FFA rules.

Nope. The RF is non-ionizing and so doesn't particularly affect pigs, so the Future Farmers of America rulebook is unsurprisingly silent on the subject [ https://ffa.app.box.com/s/z6bkjdmqd7e329a58a27e5xn1fzcqeqq ]. The Federal Communications Commission, on the other hand, cared quite a bit because it didn't want you generating snow on the TV set in the apartment immediately above yours.

[+-^CrossBow^-]

43 minutes ago, Walter Ives said:

The FCC radiation specifications applicable to the original Intellivision were very tight, because before video games and home computers nobody cared and the FCC erred on the side of caution in adopting them. When video games and home computers came out the manufacturers asked the FCC to review the standard. The FCC's job is to enable technology, and adapting its standards to the changing world is part of that charter. By the time the Intellivision II came out the standard had been revised and the new configuration was able to meet it without the full shield. The Intellivision II was actually not completely without shielding: the RF circuitry in the Astec modulator is fully encased.

NES, SMS, Genesis,...all had fully encased RF modulators in them. In the case of the NES, the RF modulator box also housed the power regulation. I remember the first time I opened up my Jpn Model 1 Megadrive and was shocked that it didn't have any RF shielding inside it? Then again, it doesn't have an RF modulator on it either and is strictly AV output. 

 

And, the intellivision II uses the same model/type RF modulator as the model 1 did. That aside, I'm still more curious why later made Intellivision II consoles don't have the fuse installed on the mainboard off the main power input where it is silkscreened? I add a small 2A pico fuse back in that spot on Intellivision IIs that come to me that don't have it installed and have a straight lead jumper in its place.