AV mod kit for Intellivision?

[ianoid]

Is this eBay link a good kit at a good price? It doesn't look as slick as some of the others pictured on the 'net, although I can't find any others for sale. And, Turkey.

 

Or can anyone recommend an AV mod for me to do myself? I'd prefer stereo output, even if it's duplicated mono, although I guess I could get a splitter cable for sound.

 

I have an original Intellivision unit with a bad RF that has a loose RF out plug resulting in an inconsistent picture. I figure I'll just AV mod it to avoid needing to replace the RF unit.

[+intvsteve]

I bought that mod kit ages ago. It's still on my 'todo' pile in the office.

 

Didn't someone here mention this was OK as a mod? Checking...

 

EDIT: Here's one thread: http://atariage.com/forums/topic/246735-av-mod-from-turkey-tips/?p=3391073

 

Sounds like "results vary".

[Greg2600]

I believe the one from Turkey is fine. I had a friend attempt to mod my system, but he couldn't get it to work properly with the TRRS (stereo AV, Composite) mini-jack I wanted to use. That's the AV cable I use for my other AV modded (non-RGB) systems. So I just stuck with RF.

[+grips03]

see the oshpark link in my signature

[mthompson]

I've used the one from Turkey, and it's quite nice. In fact, I plan to get another one for a second console in the near future. The sound is mono, but you can easily install two audio jacks and just wire them together rather than use an external splitter. That's what I did.

 

You can save a few bucks on his mod by ordering direct from his website: http://www.coolretroprojects.com

[+intvsteve]

I've used the one from Turkey, and it's quite nice. In fact, I plan to get another one for a second console in the near future. The sound is mono, but you can easily install two audio jacks and just wire them together rather than use an external splitter. That's what I did.

 

You can save a few bucks on his mod by ordering direct from his website: http://www.coolretroprojects.com

 

You can use this instead of more drilling and soldering, too. EDIT: At least, that's what I'll probably do, being so lazy I haven't installed the one I got years and years ago.

 

https://www.monoprice.com/product?p_id=7186

 

Or this if you want one long cord and two short ones:

https://www.monoprice.com/product?p_id=7187

 

Maybe this one, if the plugs are a standard distance apart - no need for patch cords, just one long one:

https://www.monoprice.com/product?p_id=7195

[ianoid]

These look more elegant than those breadboards, but I don't have a workbench stocked with parts, so I'd have to order all the parts. Wouldn't mind building it if I could get a kit with parts.

 

see the oshpark link in my signature

 

 

Thanks for the replies. I'll order the Turkey one, mainly because it's the only turnkey offering available. Usually I turn to Console5 for these things, but they don't have mods stocked, just cap kits.

[+grips03]

These look more elegant than those breadboards, but I don't have a workbench stocked with parts, so I'd have to order all the parts. Wouldn't mind building it if I could get a kit with parts.

 

 

 

Thanks for the replies. I'll order the Turkey one, mainly because it's the only turnkey offering available. Usually I turn to Console5 for these things, but they don't have mods stocked, just cap kits.

 

 

I can mail you one for $15 shipped. All parts are on the board. Just need to solder in.

or

I have a used one for $11 shipped. Shipping assumes US.

[ianoid]

 

 

I can mail you one for $15 shipped. All parts are on the board. Just need to solder in.

or

I have a used one for $11 shipped. Shipping assumes US.

 

Dang! I would have gone for it, but I already ordered the other one. Didn't realize an unpopulated board was not the only option!

[+grips03]

 

Dang! I would have gone for it, but I already ordered the other one. Didn't realize an unpopulated board was not the only option!

No worries. I try to post most of my projects on OSHpark for people to use for free. I only post stuff I've tested and ensure works, so sometimes I have a few spares. In this case I have two I'm not using.

[First Spear]

I am still open to buying an RGB-modded Inty...

[+grips03]

I am still open to buying an RGB-modded Inty...

see this thread.

 

http://atariage.com/forums/topic/266765-aquarius-rgb-interface-with-pixel-correction/

 

Bruce's board works awesome to Sony PVM. It does not work with OSSC. Pretty sure its the OSSC's fault. I get mixed results with XRGB2. i.e. works good to Samsung LCD TV, does not work to Sony LCD TV.

 

edit: Colors are slightly off, but that is easy enough to change resistors to get it to look right. I plan to test this more after I complete my other projects. Most likely in April or May.

[+-^CrossBow^-]

I've used the AV kit from Turkey several times. I've always gotten good and consistent results. But I've only installed that kit into standard 2609 intellys and my Sears unit. The kit looks great on my CRTs and also on my LED HDTV. However, be warned that ordering that AV mod board you need to have patience. Last time I placed an order, was for 3 board because of the wait time before I get them. Took 1.5 months from the shipping notification before they were in my mailbox. Good thing the customer's Intellys I was modding were most patient as well!

 

So yeah...good AV board, but you will have to wait quite a while to actually get it in hand. All three times I've ordered them...it was at least a month wait with the last order taking the longest to receive.

 

I've got one of this boards left on hand currently and 2 others from another vendor I've not actually tried yet. But they look to be built on the same schematics. The one from the Wiki page I believe that Joe originally developed.

[Ikrananka]

see this thread.

 

http://atariage.com/forums/topic/266765-aquarius-rgb-interface-with-pixel-correction/

 

Bruce's board works awesome to Sony PVM. It does not work with OSSC. Pretty sure its the OSSC's fault. I get mixed results with XRGB2. i.e. works good to Samsung LCD TV, does not work to Sony LCD TV.

 

edit: Colors are slightly off, but that is easy enough to change resistors to get it to look right. I plan to test this more after I complete my other projects. Most likely in April or May.

 

 

Any update on this? Does it still not work with the OSSC with the latest firmware (v0.81)?

[+grips03]

We were told it will never work with OSSC by the OSSC team.

[Ikrananka]

We were told it will never work with OSSC by the OSSC team.

 

Oh well, looks like I'll stick to a composite mod then. Do you know what the best composite mod is? Looking at the retrofixes, coolretroprojects and your oshpark board, they all seem to be based on the Intellivision wiki schematic and so I suspect they'll all produce the same quality output. Or are there differences amongst them that I'm missing?

[+grips03]

I think they are all the same. Mine is more for the DIY type person. If you have less time and more money then other ones should be fine.

[rmzalbar]

It looks like the same design as the Joe Zbiciak schematic on the Intellivision wiki, with a minor difference of a 680R substituted for 660R, and a much bigger change of 47R substituted for 22R.

 

I installed the Retrofix one, which is also reference design except with the 680R instead of the 660R (which really makes little difference.)

 

However, on my 2609 (Intellivision I) I had awful video on both LCDs and my real CRTs, with the wrong colors overdriven to the point where everything was compressed up into some neon green nuclear waste zone, with blurry colors bleeding everywhere. So today I decided to play with the resistors and was able to get normal video with the following two changes:

 

I first replaced 680R with the reference 660R which brought some improvement, and then replaced the reference 22K with a 10K (actully I piggybacked an 18k so the exact value is 9.9K but that's close enough). This made a huge difference and brought sharp video with correct colors for all my LCDs and CRTs. I do not know why the reference design was so poor for my unit. I should have hooked it to an oscilloscope, but I've never looked at a composite signal before so I would have had to learn what was acceptable first.

 

Anyway.. I also replaced the modulator as mine was getting its sound mixed into the video (Astrosmash test..) so now I have great composite and great RF.

Edited January 20, 2020 by rmzalbar

[+Lathe26]

2 hours ago, rmzalbar said:

It looks like the same design as the Joe Zbiciak schematic on the Intellivision wiki, with a minor difference of a 680R substituted for 660R, and a much bigger change of 47R substituted for 22R.

 

I installed the Retrofix one, which is also reference design except with the 680R instead of the 660R (which really makes little difference.)

 

However, on my 2609 (Intellivision I) I had awful video on both LCDs and my real CRTs, with the wrong colors overdriven to the point where everything was compressed up into some neon green nuclear waste zone, with blurry colors bleeding everywhere. So today I decided to play with the resistors and was able to get normal video with the following two changes:

 

I first replaced 680R with the reference 660R which brought some improvement, and then replaced the reference 22K with a 10K (actully I piggybacked an 18k so the exact value is 9.9K but that's close enough). This made a huge difference and brought sharp video with correct colors for all my LCDs and CRTs. I do not know why the reference design was so poor for my unit. I should have hooked it to an oscilloscope, but I've never looked at a composite signal before so I would have had to learn what was acceptable first.

 

Anyway.. I also replaced the modulator as mine was getting its sound mixed into the video (Astrosmash test..) so now I have great composite and great RF.

Do you have a photo of the changes you made?  I bought the same RetroFixes one and am also getting significant color smear.  I've been looking at it on the

oscilloscope and noticed that the board adds a fair amount of rounding off the edges of the input signal (adding a modest RC curve).  I don't know if that's the root cause but changing the resistors like you did might help that issue. 

[rmzalbar]

8 hours ago, Lathe26 said:

Do you have a photo of the changes you made?  I bought the same RetroFixes one and am also getting significant color smear.  I've been looking at it on the

oscilloscope and noticed that the board adds a fair amount of rounding off the edges of the input signal (adding a modest RC curve).  I don't know if that's the root cause but changing the resistors like you did might help that issue. 

Didn't take a photo of the after, but I just removed both resistors and reattached them piggybacked to a 22k and an 18k to change the total values. Reducing the resistance of the lower resistor reduces the amplification of the second transistor by a lot. If you think the smear is related to RC filtering, you could try smaller values for the three 100uf capacitors in the video section, which are the upper two and the lower left. Joe Zbiciak page explains that smaller values (even as low as 4.7uf?) might even be better. I do think there's some room for improvement, as sharpness doesn't quite equal the RF output even after my changes.

 

The page also suggests that "smearing of solid areas might be fixed by a large (2000uf??!) capacitor between +5vdc and GND." I tried this, because I am getting some digital noise visible in solid areas while the Intellivision is accessing RAM, and it made no difference, so I removed it. The board and the patch wires are all running underneath the power supply board and its wiring, and I have a feeling that maybe replacing it with coax might help, so I'll try that tonight. If that doesn't do it, I'll hook up the scope and see if I can figure out where it's getting into the video.

 

Edited January 20, 2020 by rmzalbar

[+-^CrossBow^-]

I install the AV board by using velcro to the top of one of the main ICs that doesn't use a heatsink near the RF Modulator. This also allows the output wires to be kept short as I installed the AV jacks on the far back left of the console or far back right if you are looking at it from the front. I've always thought part of the noise issues are due to the placement of the A board near the power section and that transformer. So might try placing the AV board in other places to help clear up the noise?

 

[Greg2600]

On 2/6/2018 at 12:51 PM, Greg2600 said:

I believe the one from Turkey is fine. I had a friend attempt to mod my system, but he couldn't get it to work properly with the TRRS (stereo AV, Composite) mini-jack I wanted to use. That's the AV cable I use for my other AV modded (non-RGB) systems. So I just stuck with RF.

Figured I'd update this, but about a year ago I had Leo at Digital Press (Springfield, NJ) fix that mod for me.  He got it working so it now can use the same TRRS cable as my 2600, 5200, 7800 and Colecovision. 

[rmzalbar]

13 hours ago, -^CrossBow^- said:

I install the AV board by using velcro to the top of one of the main ICs that doesn't use a heatsink near the RF Modulator. This also allows the output wires to be kept short as I installed the AV jacks on the far back left of the console or far back right if you are looking at it from the front. I've always thought part of the noise issues are due to the placement of the A board near the power section and that transformer. So might try placing the AV board in other places to help clear up the noise?

I ended up replacing all wiring with 75-ohm mini coax. Of course, the impedance isn't so important on the input side of the amp, as the Intellivision output isn't even close to 75R, but the shielded wire should have helped anyway. It made no difference however. I suspect the noise I see when the Intellivision is "thinking" (looks like faint, marching checkerboard squares on large areas of solid color) is actually 5V power supply level shifting. If so, maybe running my own 5V regulator off the 12V line as some suggest with the solarfox mod might be the ticket there.

Edited January 22, 2020 by rmzalbar

[rmzalbar]

On 1/20/2020 at 12:10 PM, rmzalbar said:

Tonight I put a 75R resistor across the composite output and hooked up an oscilloscope to either side of that resistor, and compared it to the ideal definition. It's pretty close. There is negative DC bias of about 120mv (which is probably not very important) and it is still overamplified by about 117mv P-2-P (which probably does make some difference). I may go back in and tweak some more. Still, it looks pretty good as it is. One of my CRTs seems to drift just a little bit on color reference depending on what's on the screen, but nothing else does.

Edited January 22, 2020 by rmzalbar

[+-^CrossBow^-]

7 hours ago, rmzalbar said:

I ended up replacing all wiring with 75-ohm mini coax. Of course, the impedance isn't so important on the input side of the amp, as the Intellivision output isn't even close to 75R, but the shielded wire should have helped anyway. It made no difference however. I suspect the noise I see when the Intellivision is "thinking" (looks like faint, marching checkerboard squares on large areas of solid color) is actually 5V power supply level shifting. If so, maybe running my own 5V regulator off the 12V line as some suggest with the solarfox mod might be the ticket there.

Interesting,

 

About 2 years ago now? I replaced both the 7805 and 7812 with DC-DC converters. But it didn't impact the results from my AV mod at all. I can tell you that after modding several Intelly 2609 models that they tend to give the best results with these comp AV kits, but I've still seen variances in their output between them. I did one where some of the colors were a bit skewed like the dark blues looking more like lighter blue or even pinkish but on a CRT it looked just fine and only did this on LCDs. But my Sears SVA looks the same on LCD and CRT and has been solid. But I'm using the kit from the guy in Turkey in my personal unit so again, I'm not sure if that somehow makes any difference. 

 

So are you saying that better and more consistent results are gotten if you change out those two resistors? If so, I likely have those on hand and could just swap them out on the 2 retrofixes boards I have here for use in future installations rather then piggy back.