-^CrossBow^-

I've yet to come across one that didn't have screws in the cart sleeve and I can safely say, I've seen the insides of a LOT of 7800s at this point. I'd be curious to know what revision 7800s these are being found in because I'm pretty sure I've worked on most if not all the variants and haven't seen any without the screws. In fact, I'm the one that usually cuts out the old masking tape that was used to cover the screws originally. But if the snap tabs on the sides were made a little larger to fit the space more, they wouldn't have needed to use the screws and could have kept the opening hollow to allow more 3rd party 2600 games to fit.

I'm not sure exactly which composite mod you have in place. The simple ones basically just tap the signal before it goes into the RF modulator and amplify it for normal TV signal use. But there are others like the UAV that reproduce a new video output signal from the various luma and chroma points off the 2600 itself. With a color missing, it seems something similar here where perhaps just one wire has come loose and isn't sending that part of the video to the composite mod board.

I'm not one of them as I was in band in high school so I know how it is pronounced hehe.

I will admit that there might be 2 or 3 that I've worked on where those screws are missing. But that is also because the plastic those screws used to screw into...is also missing. Done to allow tigervision and super charger carts to seat in fully.

It arrived without those screws? So someone has been inside this before then? I'm not sure the exact size but I might be able to find out later. However, even without them, with the top cover on, the cartridge sleeve should still stay in there pretty secure.

They only have one crystal in them that I've found. It is always near C2 and U10 the color chip since adjusting C2 directly impacts the video output.

Last few things I've sent or have been sent to me via USPS have actually been arriving a day ahead of their scheduled deliveries. So it would seem for the moment, that the USPS has their act together for packages going to the central US.

Nissan is obviously a sponsor LOL!

The GND point that I use is next to L6 and is part of the main ground. The +5 is all over the lynx 1 mainboard. In fact it is way more difficult to find other locations tied to gnd on the lynx than +5 as even the copper foil and RF shield is on the +5 ?! Anyway, I gave up on that lynx last night. Couldn't find any shorts from the AC/battery side to the power stage at all. It did have quite a bit of corrosion around U6 in places. So much that I removed U6 to clean it up and then soldered it back down before swapping it out and had it semi working until the AC adapter was supplied. And yes, you are correct, without the backlight tube inverter power board in place, the Lynx draws half the current it would normally require.

This is a known issue in the way the audio was done on your AV mod. All the basic composite mods seem to tap audio the same way and the way they are doing it is fine for normal carts and concerto but deviates from the proper mixing that the original circuit on the mainboard was doing. As a result the TIA audio is cancelled out when the DF cart is used. Current fix is to have the audio redone in a similar fashion as I do with the UAV installs. Essentially restore the audio components that were removed as part of the original AV mod and redo it in a manner that works with the DF cart and all other carts as well. It is unknown if stereo mods from the TIA that have been wired in will work properly with the DF cart since I personally don't offer stereo mods on the 7800 and therefore unable to test that. @seattlematt1976 I assume you are located in the US given your username?

@Stephen Moss This lynx has the power inverter section removed for the backlight and LCD section as it was supposed to get an LCD upgrade into it. So I've been taking my voltage measurements from the GND and VCC points where that board used to be attached. Yesterday I replaced out U6 from a spare Lynx 2 as I mentioned and that at least allowed me to run it off the bench supply set to 9v with those points I mentioned above reading at about 4.86v which is exactly where I would have expected it to be. Increasing the voltage on the bench supply to about 12v the reading stayed the same 4.84 - 4.87v. Near as I can tell the battery wire leads on the Lynx 1 are straight to the same traces that the AC adapter is plugged into so I've always used that in the past to feed the lynx 1 to simulate battey use etc. In probing U6 I don't recall which pins right now, but I was actually getting readings of 0v or -9v using the GND off where the high voltage section used to be located. But I can probe those pins using the main gnd.

I did purchase one of the new boards. But my plan is to initially swap it out with the one I have in my Intelly 2 now which is the older board design and what my first video pretty much already covered. However, I did get get in another Intellivision that I need to see if I can repair it and bring it back to life first and then see about putting one of these new boards into it.

Well, there is a bit of an update though no real answers. This morning I spent over 4 hours working on it going through the schematics etc. They all pointed to U6 in some way. So I replaced it from a spare lynx 2 along with replacing the zener again. Once I did that it was actually powering on and I could increase the supply on my bench PSU without the Lynx going into over volt and pulling down massive currents. In fact it was hovering at just under 500mA while operating and I felt pretty good about things. Starting putting it all back together and then powered it from the AC adapter, and this time it wouldn't power on at all? So I broke it all down and tried again. Nothing, it appears to just be totally dead at this point. It will have to go on a back burner and be replaced with another working but needs recapped Lynx model 1 mainboard. Perhaps when I've got some spare time I can come back to it and try and troubleshoot it some more.

Yeah I suggested more venting in an early post. Although I also stated that swapping out the 7805 with a DC-DC regulator would help quite a bit as well. But still requires more venting on the front sides to help with the 6502 and the other big chips to have someplace for that heat they give off to go. The 6502 especially gets hot and I've thought of sticking a heatsink onto mine to help draw that heat aware from the chip package.

Got a lynx 1 I've been working on pretty much all day at this point. Here is the basic issue with it: - Only works when input voltage is 8.8 - 9v from the battery or AC input section. If you go above 9.2v - 9.5v the Lynx will essential lock up and the current draw on my bench supply rockets to about 2A? - If you use the AC adapter (Measuring 14.5v without load), the lynx will not come up and. After a few seconds one of the RAM chips will be scorching hot along with the fet. Here is what I've done: - Replaced the ZD1 zener twice in case the first one wasn't working that I put in - Replaced the mosfet 2x in case the one I installed wasn't working right - Replaced both 3906 at Q4 and Q13. Q13 replaced twice because the first one developed a short internally when I first tested it from AC power. - Verified continuity with all the power stage components and with U6. No shorts found or breaks in the traces. I'm really stumped on this one. It will work with +5 sent straight to C39 to bypass the power stage and will read +4.87v at TP15 With the bench supply at exactly 9v the lynx comes up but I'm getting a reading of 8.3 - 8.5v from TP15 which, seems awefully high? It seems this Lynx is incapable of regulating its voltage properly. What else be sides the zener, fet, and 3906s is there that would control any of the voltage regulation?