Sanyo 20EZ help - DKong

[Mattspad]

I have now removed the chassis and the flyback has the black gunk on top...I guess I need to replace this also!.....and the sound board with gunk coming from caps may explain why I have no sound (just clicks)

Nah that black shmooze does nothing, don't replace the flyback unless your monitor is totally dead, or it's internally arcing and that's commonly how sanyos fail if they do. The symptom you'll see is the image flys off the screen and you hear a click then it snaps back then it flys off again and you hear the click and it just keeps doing that. Others will disagree but there's only 3 monitors you should replace the flyback regardless if it's working and thats the g07 because the flybacks like to explode, and k7000's and sharp xms because the cases for the flyback usually fail and they have an extremely high failure rate.

You've got several blown caps on that sound board. Use vinegar to neutralize the acid. Typical sanyo cap explosion, yes that explains the lack of sound.

 

[RetroCJT]

I have now removed the chassis and the flyback has the black gunk on top...I guess I need to replace this also!.....and the sound board with gunk coming from caps may explain why I have no sound (just clicks)

The sound board gunk is definitely bad caps as that looks like electrolytic fluid that has dried and crustified. As for the flyback, I know way back on old TV sets the flybacks used to be "potted" in wax to help insulate them from arcing internally and protect other components from high voltage arcing out. I am not sure if the more "modern" flybacks still used wax, but from my experience working on older television sets, that looks identical to wax leakage.

If the picture looks good after a cap kit, I would not bother with replacing the flyback. Even with wax leakage, a factory Sanyo flyback will be infinitely better than what are available for replacements these days.

 

[RetroCJT]

Nah that black shmooze does nothing, don't replace the flyback unless your monitor is totally dead, or it's internally arcing and that's commonly how sanyos fail if they do. The symptom you'll see is the image flys off the screen and you hear a click then it snaps back then it flys off again and you hear the click and it just keeps doing that. Others will disagree but there's only 3 monitors you should replace the flyback regardless if it's working and thats the g07 because the flybacks like to explode, and k7000's and sharp xms because the cases for the flyback usually fail and they have an extremely high failure rate.

You've got several blown caps on that sound board. Use vinegar to neutralize the acid. Typical sanyo cap explosion, yes that explains the lack of sound.

This

 

[Fenneys]

The sound board gunk is definitely bad caps as that looks like electrolytic fluid that has dried and crustified. As for the flyback, I know way back on old TV sets the flybacks used to be "potted" in wax to help insulate them from arcing internally and protect other components from high voltage arcing out. I am not sure if the more "modern" flybacks still used wax, but from my experience working on older television sets, that looks identical to wax leakage.

If the picture looks good after a cap kit, I would not bother with replacing the flyback. Even with wax leakage, a factory Sanyo flyback will be infinitely better than what are available for replacements these days.

Thanks for this I will hold off on the flyback for now

 

[Fenneys]

This

Appreciated

 

[Fenneys]

Nah that black shmooze does nothing, don't replace the flyback unless your monitor is totally dead, or it's internally arcing and that's commonly how sanyos fail if they do. The symptom you'll see is the image flys off the screen and you hear a click then it snaps back then it flys off again and you hear the click and it just keeps doing that. Others will disagree but there's only 3 monitors you should replace the flyback regardless if it's working and thats the g07 because the flybacks like to explode, and k7000's and sharp xms because the cases for the flyback usually fail and they have an extremely high failure rate.

You've got several blown caps on that sound board. Use vinegar to neutralize the acid. Typical sanyo cap explosion, yes that explains the lack of sound.

Appreciate it

 

[Fenneys]

An update to assist others...

the monitor is now nearly fully working after the below actions:

• Full wash and clean of chassis
• Full cap kit - several blown and leaking
• Full cap kit and transistors on audio board
• Replaced pots on the neck board - two were difficult to turn
• Replaced degauss circuit cap/diodes - wasn't working
• Reflowed several areas of the board - checking every area for cracks / cold solder joints
• B+ checked and placed at 108V - holding steady
• Degaussed with wand
• Moved yoke and rings
• Connected TPG
• Full recap of Nintendo power supply (all voltages now correct) - several blown caps

Still to do

• Replace pots on adjustment board and HHold on chassis (struggling to hold)
• Still some small adjustments to do with purity/yoke rings to fully dial in
• PCB out for repair, audio still not working and several sprite issues

Thanks for all the help as always
Sean

 

[nerdygrrl]

An update to assist others...

the monitor is now nearly fully working after the below actions:

• Full wash and clean of chassis
• Full cap kit - several blown and leaking
• Full cap kit and transistors on audio board
• Replaced pots on the neck board - two were difficult to turn
• Replaced degauss circuit cap/diodes - wasn't working
• Reflowed several areas of the board - checking every area for cracks / cold solder joints
• B+ checked and placed at 108V - holding steady
• Degaussed with wand
• Moved yoke and rings
• Connected TPG
• Full recap of Nintendo power supply (all voltages now correct) - several blown caps

Still to do

• Replace pots on adjustment board and HHold on chassis (struggling to hold)
• Still some small adjustments to do with purity/yoke rings to fully dial in
• PCB out for repair, audio still not working and several sprite issues

Thanks for all the help as always
Sean

Great work! These can be intimidating to work on if you have never done it before.

 

[Mattspad]

Excellent work, another day another DK!


Time to start on pcb repair. Good place to start is removing all socketed chips with an ic removal tool don't use a screwdriver. Clean the legs carefully with a fiberglass pen or file, there's several methods but be careful not to bend or damage any legs. Put them back in. If that doesn't fix it you could have bad sockets, bad eeproms, bad cpus, bad ram, or bad ttl chip somewhere

 

[Fenneys]

Great work! These can be intimidating to work on if you have never done it before.

Thank you - we learn something new everyday!

 

[Fenneys]

Excellent work, another day another DK!
View attachment 861955

Time to start on pcb repair. Good place to start is removing all socketed chips with an ic removal tool don't use a screwdriver. Clean the legs carefully with a fiberglass pen or file, there's several methods but be careful not to bend or damage any legs. Put them back in. If that doesn't fix it you could have bad sockets, bad eeproms, bad cpus, bad ram, or bad ttl chip somewhere

Thank you - Already sent it off to Starbase Alpha...... would have been happy to do sockets etc...just if I had bad eproms I dont have the tools to resolve.....just a waiting game now!

 

[Mattspad]

Good call, I would've recommended you send it off to someone experienced if the basics didn't work. When it comes to game pcb repair it's quite a step beyond monitor or power supply repair and you have to be extremely good at soldering to not lift traces on the game pcb. It also requires special tools, training, and lots of experience. Better safe than sorry, can't wait to your game running!

 

[Fenneys]

Good call, I would've recommended you send it off to someone experienced if the basics didn't work. When it comes to game pcb repair it's quite a step beyond monitor or power supply repair and you have to be extremely good at soldering to not lift traces on the game pcb. It also requires special tools, training, and lots of experience. Better safe than sorry, can't wait to your game running!

Its on it way Home now after being fixed by Ray..issues below (so it was a mixture of monitor and pcb issues)..

Green stuck on - broken leg on Q10
No sound - broken leg on Q3
Tiles wrong and duplicated - bad LS157 on video PCB at 2S
No digital sounds - bad 8035 sound CPU
Replaced all original IC sockets

 

[sfspanky]

Its on it way Home now after being fixed by Ray..issues below (so it was a mixture of monitor and pcb issues)..

Green stuck on - broken leg on Q10
No sound - broken leg on Q3
Tiles wrong and duplicated - bad LS157 on video PCB at 2S
No digital sounds - bad 8035 sound CPU
Replaced all original IC sockets

Ray is the best. Love supporting him and sending my business his way

 

[nerdygrrl]

Thank you - Already sent it off to Starbase Alpha...... would have been happy to do sockets etc...just if I had bad eproms I dont have the tools to resolve.....just a waiting game now!

Would you mind PM'ing me their info? I can't seem to find them in the member list.

 

[rod90]

yaryar

 

[Fenneys]

Board received back from Ray and now working (just a resistor to swap out on the sound board due to distorted buzzy sound)

Thanks everyone for all your help..another original donkey kong survives!

 

[Fenneys]

R383 fusible resistor replaced on sound amp pcb…now sounds perfect!!!…