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New colecovision user, I really hope ;) - Both CVs are not working...


Eric M

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Hi

Some days ago, friends of mine gave me 2 CVs, one RevD version and the other... I've forgotten (I'm too old maybe )

Unfortunaltely, the CVs don't work. Oh yes, they are French PAL/SECAM (scart)


For the first one, when I switch it on, my tv screen switch to AV chanel but it's a wonderful black screen (when I switch off the lights of my room, I can see a kind of tiny horizontal blue line under or over the middle of the screen and that's all, cartridge insterted or not)
- I've tested the voltage and it seems to be ok
- I've cleaned the power switch too


For the second one, rev D, it's simple : nothing :(
The voltage seems to be good too
The TV don't switch to AV chanel (only snow...)
The power switch is working

I've seen on the net that it could be ram, sram, many sources...

Could you please help me researching the faults to have the chance having one or two working CVs ?
Tell me they are not dead ;)


Thanks a lot

I would love to test some games and create something on it, even if it'll be hard and very very long

See you



Eric, old retrocomputer user (amstrad, amiga, falcon,...)

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The voltage seems to be good too

 

 

I'm assuming you mean voltages, as it is a few to check. Do you mean that you checked at the plug which plugs into the console or also as well checked voltages in the console?

 

If not already check the power supply to make sure you have the +12V, +5V, and the -5V on the supply.

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My favorite is to connect directly to headphones the pin 7 of SN76489 (center pin of jack and the other to ground) while putting a Frogger cartridge, as it will start playing music immediately.

 

If it doesn't work, it will be harder to make it to work.

 

Here are some guidelines http://atariage.com/forums/topic/244910-power-on-a-cv-board/#entry3352318

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Hi

 

@ SignGuy81 > I have just tested the power supply and have :

black - red > 12.02v

black - blue > -4.95v

black - white > 5.19v

After this test, I've take off the powerswitch and I'm cleaning it

 

@nanochess > Unfortunately, I don't have frogger... Is it the one and only one game booting with music ??

 

Tanks again and stay tuned

 

Eric

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Hi

 

@ SignGuy81 > I have just tested the power supply and have :

black - red > 12.02v

black - blue > -4.95v

black - white > 5.19v

After this test, I've take off the powerswitch and I'm cleaning it

 

@nanochess > Unfortunately, I don't have frogger... Is it the one and only one game booting with music ??

 

Tanks again and stay tuned

 

Eric

 

Don't remember right now.

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Just because your power supply is reading the correct voltages doesn’t mean that it’s not the problem. The power supply is filled with electrolytic filter capacitors that could have failed leaving behind excessive RFI and ripple in your output voltages.

 

I have repaired about 5 or so CV power supplies and even in cases where the supply still worked their electrolytic's hardly ever checked in spec on my ESR meter so changing them out is definitely not a bad move.

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@thecrypticodor > I will try your advice

 

@SignGuy81 > I have checked the voltage from the motherboard and it's ok

 

I have cleaned the powerswitch and there is something on my snowy screen. You can see here : http://ericmcolleco.free.fr/CVs/cv_revd.mp4

On the video, from 0 to 9s, cv is off. From 10 to... cv is on

 

 

See you and thank you ;)

Edited by Eric M
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