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Author Topic: So I found this G7000 in a basement...  (Read 4519 times)
Metrolf
Trying to get the cartridge in...
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Posts: 17


« on: April 07, 2014, 05:45:39 PM »

...and long story short, I want to bring it back to life Wink

An introduction:
I recently joined the forums in the hopes of getting some clues as to where to start. Seems like there's some people on here who knows what they're doing Wink I got some experience with electronics and modding already. Been a member of the Benheck forums for about 6 years and I've made a few portables, some RGB-mods etc. , and won a Arduino-competition somehow Cheesy Currently working on a bachelor in electronics as well, but after 7-9 months I haven't really learned much useful yet so a big applause for Norwegian schools isn't exactly in order. Basically just dipped my toes as of yet, so I'm hoping to start passing some exams soon...  Tongue

On to the heart of the matter:
Helped a buddy clean out his fathers moldy basement last weekend and found a Philips G7000 and 3 games, all in pretty bad shape. No controllers, no power supply. I've tried adding 5V 1A to it and hooked up the RF-cable to my old CRT, but no sign of life, gonna try to find a power supply with more amps. Ordered a Composite-kit on ebay in the hopes of getting it working someday, who knows, maybe it just the rf-adapter that's faulty. I'll cross the RGB bridge when I get to it Tongue As a best case scenario, I'm thinking I'll add a power switch, power indicator, and maybe a scart-out.
It looked like someone opened this at some point, but can't tell if anything has been done on the inside. I tried cleaning it roughly, pulled a dead bug out of one of the gamepacs, and removed an insane amount of hair from the cartridge connector and reflowed a few pins without really having any plan to what I was doing.  Tongue
As a first step, I guess I need some help finding out if the system is actually working.

I'll put up some pictures of the board:
« Last Edit: April 07, 2014, 06:11:27 PM by Metrolf » Logged
Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #1 on: April 07, 2014, 09:11:02 PM »

Just hooked it all up with a 5V 2A power supply, connected the rf-adapter straight to the tvs aerial plug and did a channel search. Nada Sad

I did try the multimeter on the pins going to the rf adapter and there was something going on. Can I connect the composite lead to a tv to at least check for signs of life?

What do I do? Does anyone see anything obviously wrong in any of the pictures? Is there a troubleshooting/repair-guide anywhere?
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Rene_G7400
Pedit5
I take the Videopac and leave the Canoli!
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Posts: 2519



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« Reply #2 on: April 07, 2014, 09:51:49 PM »

Have you checked the schematics of the G7000 yet?
You can find them on this page:
http://home.kpn.nl/rene_g7400/vp_info.html

The best thing to do is to check some frequencies (can be done without cart):
- the ALE pin (11) of the 8048 should be 394 kHz
- the HBL pin (7) of the 8245 should be 15.6 kHz
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Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #3 on: April 07, 2014, 11:04:24 PM »

Allright, thanks! I can probably bring the whole thing to the lab at school and make use of their oscilloscopes... I'll try it out this weekend.

Checked the 5+ to the rf-adapter and it was at 3,6v so I changed to a 9v source which put it at the desired 5v. Then I ran the whole test with the channel search again, still dead... Also checked the audio. Is it supposed to have an amplitude of 2,8v?
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Nognir
Attacked the Timelord
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« Reply #4 on: April 08, 2014, 12:12:08 AM »

A big "Hello!" from my side and I hope that you manage to fix the G7000. It will be worth fixing it! Smiley
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Real games need only one button
Rene_G7400
Pedit5
I take the Videopac and leave the Canoli!
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Posts: 2519



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« Reply #5 on: April 08, 2014, 09:42:11 AM »

Also checked the audio. Is it supposed to have an amplitude of 2,8v?

You could connect the audio output to an audio amplifier to check if there's any signal on it.
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Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #6 on: April 08, 2014, 10:03:12 AM »

Also checked the audio. Is it supposed to have an amplitude of 2,8v?

You could connect the audio output to an audio amplifier to check if there's any signal on it.


I was actually prepping a cable to do just that last night;) A small speaker didn't do much, will try my amp next!
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Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #7 on: April 08, 2014, 02:16:44 PM »

Instead of making a new post just for this, I'll just ask here:

I figured that I might as well get a controller for it sooner than later and since the official joysticks is pretty expensive, can I get one of these Atari-sticks http://www.ebay.com/itm/NEW-Atari-2600-5200-Commodore-Joystick-Controller-/371026532146?pt=US_Video_Game_Controllers&hash=item5662e79732, and just rewire/ make an adapter-cable?
Seem to recall reading somewhere that they worked the same, but with rearranged pinout. Is that correct?
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Rene_G7400
Pedit5
I take the Videopac and leave the Canoli!
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Posts: 2519



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« Reply #8 on: April 08, 2014, 04:32:07 PM »

If it's a joystick with just 5 switches inside without additional electronics, it should work with some rewiring.
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Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #9 on: April 08, 2014, 08:09:31 PM »

Also checked the audio. Is it supposed to have an amplitude of 2,8v?

You could connect the audio output to an audio amplifier to check if there's any signal on it.


I was actually prepping a cable to do just that last night;) A small speaker didn't do much, will try my amp next!

Just tried to amplify the audio directly from the board, and wow, that was a lot of noise, loud crackles and indistinct fuzz :/ So something is going on with it, but if that something is what it's supposed to be, I ain't sure... I'll try testing the frequencies, like Rene said, this weekend, while waiting for the Composite-kit.
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Rene_G7400
Pedit5
I take the Videopac and leave the Canoli!
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Posts: 2519



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« Reply #10 on: April 09, 2014, 09:34:12 AM »

If you can use an oscilloscope you can also check if any video signal is going into the RF modulator.
If there's no signal on the ALE pin of the 8048, you should check if there's a clock signal on pin 2 of the 8048 (5.91 MHz).
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Define
Attacked the Timelord
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Posts: 125



« Reply #11 on: April 09, 2014, 04:08:46 PM »

If you want it, i've got a good working G7000 that i'm going to sell and some cartridges. (got another one already)
But i can imagine you want to repair this one maybe first.

 
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Videopac 4 life
Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #12 on: April 09, 2014, 05:05:33 PM »

If you want it, i've got a good working G7000 that i'm going to sell and some cartridges. (got another one already)
But i can imagine you want to repair this one maybe first.

That's a great offer, however I will try to fix this one first, yeah. I realize the chances of it being beyond repair are pretty high, but I would probably enjoy fixing it just as much as just owning and playing one Wink It's a surprisingly cool system though, had only just heard about it on Classic Game Room on Youtube. I might take you up on your offer still, however I'm dangerously close to beeing broke right now Cheesy
« Last Edit: April 09, 2014, 10:19:56 PM by Metrolf » Logged
Rene_G7400
Pedit5
I take the Videopac and leave the Canoli!
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Posts: 2519



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« Reply #13 on: April 10, 2014, 09:31:29 AM »

If you need to replace the 8048 or 8245 ICs you'll need another G7000 console anyway.
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Metrolf
Trying to get the cartridge in...
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Posts: 17


« Reply #14 on: April 10, 2014, 12:59:16 PM »

Yeah, I realize that Undecided Would you say those chips are the most likely thing to be wrong with the system?
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