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Atari 7800 SVideo UAV Mod

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Atari 7800 Modding Adventures

 

Welcome to my adventures in modding my Atari 7800 for use on ZPH! I'll be installing TBA's UAV mod for some nice, clean svideo output.

 

Step 1: Test my Atari 7800's, joysticks, carts and Concerto Cart!

 

Systems: I have two (three actually, one's in a box but I'll leave that one there) Atari 7800's and both of them work great along with the power supply for both of them. The second one is great for a backup in case I destroy one in the process. The second one didn't turn on the first time I tried and is a little rougher looking so I'll be modding the one that turned on first try. The output from both is crystal clear on my 1702 Commodore monitor.

 

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Joysticks: I have three 7800 joysticks, two of them work well but the third one has a finicky left button. I've marked that joystick so I can take a look at it later and fix it. One of the working joysticks, the metal plate has come unstuck, any advice on what to use to stick it back on?

 

I'll be ordering a Super Twin 78 as soon as the borders open up again, the shipping to Canada from the US for bigger packages like that is just way too crazy, I can just hop over the border and back again and save a ton on shipping.

 

Carts: I tested out Galaga and Xevious on cart, and both work great! The picture output is awesome for RF and the sound is great too, total success. 🙂

 

Concerto: Here comes the exciting part, the Concerto works great(ish) too!

 

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I first tried a 2GB card in the system but it didn't show a directory listing.

 

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This is a known issue and is being worked on. Larger cards are being reported as working so I grabbed a 16GB and it showed the files I put on it, hooray!

 

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Of course I had to try Popeye as the first homebrew and it looks amazing! I haven't got the Pokey donor cart (PAL Ballblazer in a crushed box) yet so there wasn't any music but I could hear the rest of the sounds and it played awesome.

 

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I next upgraded the firmware to the newest 0.93 (0.94 is a test firmware to slow down access for slower cards). There are some issues with navigating folders that freeze up the cart quite often, but they're being worked on and should be fixed in the next firmware.

 

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Here's some fun screens from Concerto for those of you who'd like to check them out.

 

First it shows the loading screen that says Concerto 1.0, then it flashes through a whole bunch of colours and boots up to a screen that lets you know it's still in work in progress. The cart also shows an error screen when you don't have an SD card in it, which is great for testing purposes just in case it's the card that's the problem and not the cart.

 

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A note of interest is that after you update from firmware 0.92 to 0.93 it changes the date from Copyright 2015 to Copyright 2020!

 

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Now that I know I have everything working great it's time to prepare for the next step... opening it up and start the modding!!

 

- James

 

Edited by ZeroPage Homebrew
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Part Two: Prepping the Audio and UAV Board. Time to start the soldering! Eeep!

 

Audio:

 

Although audio is not part of the UAV mod kit, it still needs to be done otherwise you won't be able to hear any sound. I was able to follow @-^CrossBow^- 's excellent video and instructions to buy the correct resistors and capacitor and get to piecing it together.

 

I had to buy way more than necessary but hopefully I can use them in future projects? Try to refrain from making fun of my soldering job on all of this, I can barely solder two wires together, hahah.

 

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And here it is soldered to the board in the correct place! I tested the phono plug out attached to the negative lead and it works great, super clean sound. Although when I attach the ground, the picture on the display goes fuzzy... maybe I'll just leave that off? That doesn't seem right...

 

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Oh yeah, here's me disassembling the 7800 and taking off the RF shield. It was quite stubborn to remove but I got it off! I read a number of posts about leaving it off after doing mods. Some said that it doesn't matter, some say put it back on but none of them say DON'T put it back on so I'll be putting it back on just in case. BAD RF, stay in and out of the 7800!

 

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Here's where all the connectors will eventually be soldered onto from the UAV board. Get ready for some blotchy soldering Mr. 7800!

 

 

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UAV Board:

 

Okay, now onto the UAV board. I've already soldered on the green watchamacallit so I can just screw down the wires onto the board, such a great idea and will make life a lot easier.

 

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Next is to do some much more fine soldering into the marked holes on the board. I chose to go with all yellow wire, because why not. After I took the picture of the underside of the board, I noticed how terrible the soldering was and redid some of them, so they actually look better than this now. One had almost no solder and one had too much. Could be worse!?

 

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Next I soldered on the +5V and ground to the board, that went a lot better and seem to be very solid.

 

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Next post will be me actually soldering the ends of the yellow wires onto the 7800 board where all those tiny resistors are, very scary times!! 😞

 

- James

Edited by ZeroPage Homebrew
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James, be sure to reach out to me if you have any questions regarding the UAV installation. I've done quite a few of these and can pretty much do them in my sleep at this point.

 

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13 hours ago, -^CrossBow^- said:

James, be sure to reach out to me if you have any questions regarding the UAV installation. I've done quite a few of these and can pretty much do them in my sleep at this point.

Thanks so much Crossbow! Your video tutorial and instructions have been a great guide for the install so far. Just got the rest of the parts I need to complete the mod and I'll be working on it some more tonight and tomorrow so I'll let you know if I run into any snags that I need some guidance with.

 

- James

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BTW I do advise leaving the RF shielding in place. But as I'm assuming you are leaving the RF Modulator intact and working given that you added in the extra resistors for the audio out. Just have to keep in mind you might have to remove some portion of the RF shield to allow for your output wires to come through whichever side you place the RCAs and s-video jacks on.

 

When you finalize your wiring, I would just use the same ground for both the audio and composite and run that to the ground point on the green terminal block next to the trimmer. But use a different ground from your s-video to the other ground next to the Maria Col In on the green terminal block. That should help with the issue you observed when you tested your audio earlier.

 

** Just noticed yours doesn't have the extra timing circuit. So confusing as it appears your 7800 is from the end of April of 1988 so it is a later made unit but without the extra circuit components being populated. So you are likely good to go for full compatibility with most of the entire 2600 library as well. Nice!

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3 hours ago, -^CrossBow^- said:

BTW I do advise leaving the RF shielding in place. But as I'm assuming you are leaving the RF Modulator intact and working given that you added in the extra resistors for the audio out. Just have to keep in mind you might have to remove some portion of the RF shield to allow for your output wires to come through whichever side you place the RCAs and s-video jacks on.

Thanks for the advice, I will now definitely be leaving the RF shielding in place. I will be keeping the RF Modulator intact, it's always better to have more options of output especially if it's not causing any issues. I'll cut a small part away in the RF shielding for the wires to go through.

 

3 hours ago, -^CrossBow^- said:

When you finalize your wiring, I would just use the same ground for both the audio and composite and run that to the ground point on the green terminal block next to the trimmer. But use a different ground from your s-video to the other ground next to the Maria Col In on the green terminal block. That should help with the issue you observed when you tested your audio earlier.

Thanks so much, I was wondering about the best configuration for the grounding. 🙂  I'll let you know how it goes with the video interference I saw on the RF.

 

3 hours ago, -^CrossBow^- said:

** Just noticed yours doesn't have the extra timing circuit. So confusing as it appears your 7800 is from the end of April of 1988 so it is a later made unit but without the extra circuit components being populated. So you are likely good to go for full compatibility with most of the entire 2600 library as well. Nice!

Very interesting, I seemingly chose the right one of my 7800's to mod by accident then! Is there a comprehensive list of variations of 7800's along with compatibility issues I can check out?

 

- James

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17 minutes ago, ZeroPage Homebrew said:

Very interesting, I seemingly chose the right one of my 7800's to mod by accident then! Is there a comprehensive list of variations of 7800's along with compatibility issues I can check out?

There used to be a 7800 FAQ here at AA. But at the moment, the page appears blank. I suppose someone should mention that to Albert. :roll: 

 

Digital Press still has a copy of it, but the formatting is hosed. Still, the info is in there. It's probably woefully out-of-date, relative to what developers know about it now.

 

Good luck with the soldering! Just remember to heat the connections, and let them melt the solder. I'm half-considering adding a UAV mod to my 7800, so I'm interested to see how this turns out.

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2 minutes ago, Nathan Strum said:

There used to be a 7800 FAQ here at AA. But at the moment, the page appears blank. I suppose someone should mention that to Albert. :roll: 

 

Digital Press still has a copy of it, but the formatting is hosed. Still, the info is in there. It's probably woefully out-of-date, relative to what developers know about it now.

archive.org to the rescue, thanks for the pointer to the old location so I could look it up! Possible 2600 game incompatibilities is a fairly short list that includes Robot Tank, Decathlon, Space Shuttle, Time Pilot, Kool-Aid Man and the Supercharger.

 

2 minutes ago, Nathan Strum said:

Good luck with the soldering! Just remember to heat the connections, and let them melt the solder. I'm half-considering adding a UAV mod to my 7800, so I'm interested to see how this turns out.

Thanks! My skills are slowly improving and if it all goes sideways I can just ship it off to you... right? Hahah, just kidding. This seems to be a fairly straightforward and simple(ish) mod, I'm just fearing pulling the Pokey from Ballblazer for the Concerto cart but luckily that's a separate task from the mod.

 

- James

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On 12/20/2020 at 5:16 PM, ZeroPage Homebrew said:

Joysticks: I have three 7800 joysticks, two of them work well but the third one has a finicky left button. I've marked that joystick so I can take a look at it later and fix it. One of the working joysticks, the metal plate has come unstuck, any advice on what to use to stick it back on?

Actually, no 7800 joystick has ever worked well, but that's beside the point. ;)

 

Best has 7800 repair kits. I need to order a couple because both of mine are completely shot. For re-adhering the metal plate, first use an adhesive remover to get rid of all remaining adhesive residue. I use Bestine. Then, get a small jar of contact cement, and follow the instructions. Epoxy would also work, but is way more permanent.

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35 minutes ago, ZeroPage Homebrew said:

archive.org to the rescue, thanks for the pointer to the old location so I could look it up! Possible 2600 game incompatibilities is a fairly short list that includes Robot Tank, Decathlon, Space Shuttle, Time Pilot, Kool-Aid Man and the Supercharger.

I have an '84 system, so I think mine is fully compatible. I don't know if I've ever actually checked it though.

35 minutes ago, ZeroPage Homebrew said:

Thanks! My skills are slowly improving and if it all goes sideways I can just ship it off to you... right? Hahah, just kidding. This seems to be a fairly straightforward and simple(ish) mod, I'm just fearing pulling the Pokey from Ballblazer for the Concerto cart but luckily that's a separate task from the mod.

Well, if you completely hose it, you're always welcomed to ship it to me if you don't mind the extra expense and time. ;) I've got a couple more of John's consoles here, including his 7800 which appears to need a new RIOT. I need to get around to fixing that one of these days.

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22 hours ago, Nathan Strum said:

Actually, no 7800 joystick has ever worked well, but that's beside the point. ;)

Somehow Atari managed to consistently bungle every controller design after the cx40.

 

IMO either the Seagull 78 and a Genesis controller is the way to go, or just modify a genesis controller with the connections and resistors required for 7800 two-button operation. Sometimes people modify an NES pad, but that's a bit more work since you can't reuse the cable. The 7800 Europad is probably a distant option to any of those, but still better than the proline controller.

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2 hours ago, ZeroPage Homebrew said:

S-VIDEO MOD COMPLETE! Update coming soon...

Pics or it didn't happen. :P

 

Also, shouldn't the title of this thread be: "Atari 7800 SVideo UAV Mod"?  :ponder: 

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26 minutes ago, Nathan Strum said:

Pics or it didn't happen. :P

Soooooooon, so much that I have to prepare for tonight. Never mind that I'm in crunch mode for the Homebrew Awards too! Hahah, I take on too much sometimes.

 

26 minutes ago, Nathan Strum said:

Also, shouldn't the title of this thread be: "Atari 7800 SVideo UAV Mod"?  :ponder: 

 

Aerial Unmanned Vectrex?

Auto Mangling Vipers?

 

Updated!

 

- James

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Part Three: Soldering the 7800 Board!

 

Here we go, the scary part of the journey! The next step of the UAV mod was to solder all those yellow wires to the Atari 7800 board on the resistors. There were seven of them and they were pretty much all in a row, skipping one. I made sure to double and triple check each of the wires and where they were going before soldering them down because I definitely didn't want to re-do this part if there was a mix up.

 

The resistors are pretty small so I made liberal use of the magnifying glass and put on the smallest tip of the soldering gun. For my skill level, I didn't think I did badly. It's definitely far from good but they all seem to hold solid under a decent tug and none of the wiring or solder is touching each other.

 

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Drilling Holes:

 

Next up is drilling the holes in the case for the three connectors: s-video jack, headphone jack and composite RCA jack.

 

First up is the s-video jack. I looked up a number of mods and where they placed their outputs but I thought that a good place would be pointing downward on the right hand side of the case. Putting them up high enough, with the s-video towards the back should give enough clearance for the cables coming out.

 

I bought the s-video connector at the same place that @Nathan Strum bought the RGB mini-din as the construction was ROCK solid and already pre-wired.

 

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I figured that the size of the thread that needs to go through the case was about 1/2 inch and then marked off the spot where I wanted to drill the hole. I started with a small drill bit and then worked my way up.

 

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It fit very nicely! BUT..... to get the nut on there was going to have to cut away some of the plastic beside it so I could thread it on. So a LOT of filing later...

 

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Next up was the hole for the headphone jack. They accidentally shipped my four pronged headphone jacks instead of three, I didn't need a microphone portion, but it will work the same regardless.

 

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And lastly, the hole for the RCA jack:

 

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WIRING THE OUTPUTS

 

Wiring up the UAV power and ground and the RCA jack was the next order of business. The RCA jack only had two wires going to it and it's the easiest to test whether it's working or not. This is when disaster struck!!

 

I don't have pictures of this unfortunately but when I was wiring the power and ground to the UAV board to test the RCA jack, I poked the power and ground through the two +5 and ground rails that run down the middle of the 7800 board. They went in fine but when I powered up the system, NOTHING... it didn't turn on. I turned it off and on a number of times and still nothing, except once in a while I could see the power light flicker on for a second. Hmm... very weird.

 

I traced all my wiring and everything looked good when my hand touched a part near where the power comes in and OW! it was burning hot!! I then thought that wiring was somewhere touching something it wasn't supposed to. I unplugged the power immediately and started looking all over. I then lifted up the board and removed the bottom RF shield and saw two shiny bare wires sticking through the board DEFINITELY long enough to both be touching the RF shield. I don't think it's a very good idea to have power and ground both touching the RF shield?? Hahah.

 

I snipped the excess wires off and BOOM, a picture!! I didn't actually destroy all my work, phew! This not only verified that the UAV board was wired correctly (so far) but also confirmed that I wired up the RCA jack to the correct spots on the board as well. The green standoff was incredible for securing the wires, all I had to do is make sure to find a small enough screw driver! It's such a tiny screw!!

 

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Next up was connecting the already tested audio and then the s-video wiring.

 

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I then took the system downstairs to the ZPH broadcast room because the C64 monitor doesn't have s-video (it kind of does, but it's a proto s-video that's not compatible). I plugged it into my Framemeister and all it would do was flicker between no picture and a terrible black and white picture that I could barely make out. Hmm... I took it back upstairs, checked all the wiring against the instructions and a wiring diagram of an s-video connector. Looks all good... Chroma, Luma, Ground... hmm... I take out all the wiring and put it back in the green block just in case there was a bad connector somewhere.

 

I took it back downstairs and it's still only flickering black and white, it looks terrible. I then look up s-video black and white and all it comes up with is irrelevant information. Hmm... okay, check over my wiring once again but it all looks good. I check over the s-video wiring diagram on the internet again and realized my mistake. EVERY SINGLE picture of the wiring of an s-video connector is from the perspective of a MALE wiring diagram, ugh... With a flat 2D shot of the pinouts I couldn't tell that it was male instead of female. I then switched out the Chroma and Luma, took it downstairs and saw the most beautiful sight... (check the 20201231 broadcast for the amazing quality).

 

CLEANING UP THE WIRING

 

I had to now put back on the RF shield so I needed a safe route cut through it at the right spot. I measured where the wires run by to get to the outputs to snip and bend away a part of the RF shield. It was quick and dirty, but it worked. I then taped up the wire around the opening so it wouldn't rub against the bare sharp metal and sever all the work I did. It was a nightmare positioning the RF shield back on to all the tiny little tabs, especially after bending the metal a bit to cut out the hole.

 

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RESULTS

 

I even impressed myself with the clean look of the outside of the case once it's all closed up! There's no visible cuts, the outputs are all nicely spaced apart (not perfectly even but not the worst) and very accessible. I do have some issues to resolve with the build that I need to address but I'll post these in another post below with some questions. Check out the final pics!

 

- James

 

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Part Four: Destroying a Pokey Chip

 

A month ago in preparation of getting everything ready I bought a Ballblazer cart off of EBay to bravely sacrifice its life so that its music can live on in the new Concerto cart. It arrive a few days ago, just in time, as I was getting everything in place for the first broadcast using my newly upgraded Atari 7800. The box was crushed so I got a decent deal on the game, I mean, I was going to take apart the cartridge anyway so I didn't care too much about the box, I just wanted a cheap working Ballblazer.

 

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So the game and sound worked great so I was ready to take it apart and remove the chip from the board. I VASTLY underestimated how difficult it is to remove a chip that's soldered onto a board.

 

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Taking a look at the underside of the chip there were 40 pins neatly soldered onto the board. Okay, that's a lot... So I got my soldering iron hot and had my manual action solder sucker ready.

 

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I went through each of the soldered pins one by one, heating it up and sucking the solder out. It took a LONG LONG time and I got it to a point where each of the pins looked really clean. I turned it over and tried to remove the chip. No dice, it didn't budge. I went through all the solder points again sucking out any remaining bits I could find. Tried to remove it again, not even a squeak. Ugh.

 

Now what... I look up some videos on how to remove chips from board and they're ALL using desoldering guns, I think I'm in trouble. Some others are using soldering wicks, which I don't have either. Hmm... so I look deeper into some videos on how to remove chips. I find one where they actually put MORE solder onto the connections warming them all up at once and then pulling the chip that way. Well, it looks like that's my only hope at this point.

 

I PILE on the solder heating up all 40 pins as best as I can. I manage to get a file underneath the chip and very slowly pry away the Pokey chip from board as I work away at the soldered connections. Of course piling on the solder has an additional effect of RESOLDERING things I just cleared out. It's a mess to put it nicely. The board is warped and the legs are splaying out like a squashed bug as I pry it away but the chip itself seems to stay intact.

 

It takes a LONG time to work the chip off of the board but I get it removed. Sadly there's a leg half snapped off and another that's completely come off. 😞

 

WARNING, GRAPHIC CHIP DESTRUCTION AHEAD...

 

 

 

 

 

PXL_20210101_001811047.thumb.jpg.c128b1d04e9e17a61b065619b66d026f.jpgPXL_20210102_013812441.thumb.jpg.982a73aee2f3734d52fecf8353039527.jpg

 

So very, very sad. I not only destroyed a chip but I also wouldn't have Pokey sound for the stream. I decide to just go ahead with the broadcast knowing I'll just let people know there's not going to be full sound. 😞 

 

So today I emailed Best Electronics in hopes of buying "Bests New Atari Custom made CO12294 Pokey Chip". Not sure what 'custom' means but if it works just like a Pokey chip then I'll be good with it until I can get a Pokey One or a Hokey etc.

 

- James

Edited by ZeroPage Homebrew
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Part Five: Question Time

 

There's still some things left to do for the mod so here they are:

 

 

1) Heat Shrink Audio Connection: No real question here, just something I need to do. I didn't have any heat shrink tubing while doing the mod so the audio is still hanging out inside the case with exposed wires, not ideal. I've ordered some heat shrink and will apply it over the exposed areas when I get it.

 

PXL_20201228_034406887.thumb.jpg.2449e76a793263cfcf1301cc2ce02d9c.jpg

 

 

 

2) Securing the UAV board: The UAV board is just hanging out inside the case and not secured to anything. I tried to secure it with double sided tape but I couldn't get it to stick to the UAV board as it wasn't really a flat surface. I tried to looking it up on the Internet but couldn't find the right search terms to get any results.

 

QUESTION: What can I use to secure the UAV board to the Atari 7800 board?

 

PXL_20201231_064131358.thumb.jpg.ab88734cdbc30bea4aa5599ebaf0cebe.jpg

 

 

 

3) Grounding the Audio: I *didn't* ground the audio during the install. Partly because I was rushed for time and the one time I did ground the audio it interfered with the RF signal and put a bunch of noise in the video. The composite and s-video seemed to look great without grounding it and the audio also sounded great too.

 

QUESTION: Should I ground the audio connector even though everything seems to work great?

 

PXL_20201231_075825318.thumb.jpg.a5e736757f099d51822d05ecf301b1f3.jpg

 

 

 

4) Protecting Wiring: The hole I cut/folded in the RF shield looks dangerous to me and I can see it easily cutting through the masking tape and then the wires after enough shifting around of the console.

 

QUESTION: What is the best way to clean up the cut in the RF shield and wrap up the wires to minimize the danger of severed wires?

 

PXL_20201231_082630784.thumb.jpg.e33e84f51974d2dcd9a8ab3f1c96cf7f.jpgPXL_20201231_082624868.thumb.jpg.73e2b66cb081e4ea9a930c61005f0617.jpg

 

 

5) Pokey Chip: As you saw in the post above, I completely destroyed a Pokey chip due to ignorance and incompetence. RIP Pokey chip. I've reached out through email to Best Electronics but I've heard they're unreliable at best in terms of responding plus I don't know if they even ship to Canada.

 

QUESTION: What are the best ways to buy a ready-to-install Pokey (or compatible) chip and is it easy to install it into the Concerto Cart?

 

PXL_20210102_013812441.thumb.jpg.2f905fb9e7a2a0fb1635a049085d91c3.jpg

 

 

 

Hopefully you (@Nathan Strum & @-^CrossBow^-) might have have some suggestions or ideas for me to pursue for help on these issues? 🙂 Thank you so much!!

 

Also, thank you again @-^CrossBow^- for your instruction sheet and install video that resulted in an successful modding experience, even for an amateur solderer!

 

- James

 

 

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I'll second the charge against Best Electronics. Very unresponsive. Their s-video mod crapped out on me not too long after they shipped back (although the composite still worked fine) and I never heard from them again.

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Yes the audio connection should be grounded. I've not noticed the audio causing any interference with anything but even if it only affects the RF, do you really care at that point too much?

 

On the output wires and the RF shielding what you need to do is fine some small files to smooth out the edges of the cut you made. In addition to that you should put some shrink tubing around the output wires right where they go through the opening as additional protection for them. However, there was a much easier way to do this. That section just to the right of where you made the hole? Well, you can get a good set of pliers to grip that section with and then bend the metal up and down along the seam and it will eventually break off very clean in most cases. That is what I do on my installs for clients. 

 

I don't have a concerto but my understanding is that there is a socket for the pokey, so the replacement should just go right into the socket. Naturally you have to pay attention and put the notched ends matching. In the future, to remove IC chips like this, you need to first add more solder to each pin. Yes add solder as it helps to melt the solder on the whole pin when you then try and use at minimum a manual solder pump or better, find someone with a de-soldering iron such as myself or someone near you to get the chip out safely.

 

@Nathan Strum where do you get those S-video jacks? I'm always in the market for replacements and new styles to use and I like the way that one looks.

 

 

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3 hours ago, ZeroPage Homebrew said:

It takes a LONG time to work the chip off of the board but I get it removed. Sadly there's a leg half snapped off and another that's completely come off. 😞

 

WARNING, GRAPHIC CHIP DESTRUCTION AHEAD...

 

PXL_20210101_001811047.thumb.jpg.c128b1d04e9e17a61b065619b66d026f.jpgPXL_20210102_013812441.thumb.jpg.982a73aee2f3734d52fecf8353039527.jpg

 

So very, very sad. I not only destroyed a chip but I also wouldn't have Pokey sound for the stream. I decide to just go ahead with the broadcast knowing I'll just let people know there's not going to be full sound. 😞 

Yeah... probably should've practiced on something else first. Like removing a ROM from a Pac-Man cart. You can always practice soldering skills on junk electronics.

 

I recently acquired a proper desoldering gun, but even a cheap desoldering iron will work (like this one). I used one like that for years.

 

The chip might be salvageable... depends on where that pin broke off, and if there's any metal left to solder to. You have my mailing address if you want to throw it in an envelope. ;) 

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2 hours ago, ZeroPage Homebrew said:

1) Heat Shrink Audio Connection: No real question here, just something I need to do. I didn't have any heat shrink tubing while doing the mod so the audio is still hanging out inside the case with exposed wires, not ideal. I've ordered some heat shrink and will apply it over the exposed areas when I get it.

 

PXL_20201228_034406887.thumb.jpg.2449e76a793263cfcf1301cc2ce02d9c.jpg

Heat shrink tubing is tubing. So you have to put it over the wire before soldering it.

 

However, you can still use it as insulation, by slicing it open and using some electrical tape to close it back up.

 

Quote

QUESTION: What can I use to secure the UAV board to the Atari 7800 board?

 

PXL_20201231_064131358.thumb.jpg.ab88734cdbc30bea4aa5599ebaf0cebe.jpg

Good question... I'm going to be modding John's 7800 in the coming weeks (now that's a train-wreck of a console - through no fault of John's). I guess it depends on how permanently you want to mount it, and where.

 

I'm likely going to make a small standoff out of some scrap plastic to elevate it above the main board, and use some Scotch outdoor mounting tape to anchor it down somewhere where there are no traces or chips. Or maybe the underside of the RF shielding. This stuff does NOT come back off once it cures though. Not without adhesive solvent.

 

Quote

4) Protecting Wiring: The hole I cut/folded in the RF shield looks dangerous to me and I can see it easily cutting through the masking tape and then the wires after enough shifting around of the console.

 

QUESTION: What is the best way to clean up the cut in the RF shield and wrap up the wires to minimize the danger of severed wires?

 

PXL_20201231_082630784.thumb.jpg.e33e84f51974d2dcd9a8ab3f1c96cf7f.jpgPXL_20201231_082624868.thumb.jpg.73e2b66cb081e4ea9a930c61005f0617.jpg

Electrical tape. Wrap it around the cut edges of the metal, and over the wires where they pass through. Don't get the cheap generic stuff. Scotch 33+ is probably best for wrapping the metal because it's pretty thick. But Scotch 35 comes in pretty colors!

 

Quote

5) Pokey Chip: As you saw in the post above, I completely destroyed a Pokey chip due to ignorance and incompetence. RIP Pokey chip. I've reached out through email to Best Electronics but I've heard they're unreliable at best in terms of responding plus I don't know if they even ship to Canada.

 

QUESTION: What are the best ways to buy a ready-to-install Pokey (or compatible) chip and is it easy to install it into the Concerto Cart?

 

PXL_20210102_013812441.thumb.jpg.2f905fb9e7a2a0fb1635a049085d91c3.jpg

I've never had issues with Best, as long as you follow their instructions for e-mailing them, and are a little patient. One look at their website should let you know this isn't their day job, but I've always gotten what I've needed from them. (I've never bought one of their pre-modded systems so I can't speak to those, but they've been great for ordering parts.)

 

The chip they sell is an Atari POKEY chip. The "custom" you referred to means that is was an Atari custom chip. Not a Best custom chip. I'll be ordering my POKEY this way. (I still have to put in an order for a Concerto one of these days.)

Edited by Nathan Strum
Deferring to Crossbow's post regarding grounding the audio.
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15 hours ago, Nathan Strum said:

Yeah... probably should've practiced on something else first. Like removing a ROM from a Pac-Man cart. You can always practice soldering skills on junk electronics.

 

I recently acquired a proper desoldering gun, but even a cheap desoldering iron will work (like this one). I used one like that for years.

 I definitely should have practiced on something else. 😞  I was anxious to have it ready the for the show that night, so I just went for it, but didn't have the proper tools. I've now ordered a heat gun and soldering wick to help in the future.

 

15 hours ago, Nathan Strum said:

The chip might be salvageable... depends on where that pin broke off, and if there's any metal left to solder to. You have my mailing address if you want to throw it in an envelope. ;) 

It might be salvageable, the pin broke off flush to the chip so it might be challenging to make sure there's contact with the metal. I might just send it to you to see if it's possible to get it working!

 

 

Thank you both @Nathan Strum and @-^CrossBow^- for the great answers to my questions, I've also ordered some heat shrink tubing and the recommended electrical tape. I'm a little hesitant to use the outdoor mounting tape as I don't want it permanently stuck there, just stuck REALLY well, but removable.

 

I'll be doing a followup post when all the additional materials come in. 🙂 

 

- James

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16 hours ago, Nathan Strum said:

I've never had issues with Best, as long as you follow their instructions for e-mailing them, and are a little patient. One look at their website should let you know this isn't their day job, but I've always gotten what I've needed from them. (I've never bought one of their pre-modded systems so I can't speak to those, but they've been great for ordering parts.)

 

The chip they sell is an Atari POKEY chip. The "custom" you referred to means that is was an Atari custom chip. Not a Best custom chip. I'll be ordering my POKEY this way. (I still have to put in an order for a Concerto one of these days.)

 

Great news, Best got back to me about the Pokey chip! I guess I was able to evade their spam filters. 🙂 Now I just have to find an additional item to meet their minimum $20 for a Credit Card order.

 

- James

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Forgot to mention that what I use to mount the UAV boards is section of 3M velcro. I have the stuff that can hold like 10LBs or something crazy but I use it because I don't need much of it to hold the thing in place. I use like a half inch by inch piece on the BIOS or one of the RAM chips and then use basically a 1"x1" piece on the UAV itself on the underside. It won't stick 100% to the components that are on the underside preventing totally smooth surface, but if you solder the wires from the resistors to the UAV first, and then trim them all down to be flush with UAV PCB, then that part is smooth enough for the other side of the velcro to hold very well! Been doing that on all of my installs for about 4 years now. This way it holds exactly where needed and isn't coming loose on its own, but yet with some work and a slot hand, you can remove all of the velcro tape off the chips without much residue left behind if you decide you want to move the UAV to a different machine or remove it completely..etc.

 

 

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