Matsushita TM202-G Issues (Pole Position)

Joined
May 21, 2016
Messages
89
Reaction score
19
Location
Victoria, British Columbia, Canada
I have a pole position upright that has an issue with the monitor at the moment, a Matsushita TM202-G. It's blowing the fuses and R809 is burning up when plugged in. I tested some of the diodes and I think that D802 and D803 might both be bad. I'm getting good voltage, 123v AC or thereabouts.

The issue started when I was working on the power supply. I took it out to do some work, and I think the ground from the monitor may not have been making a good connection when I turned it all back on.

I was wondering if anyone else has seen something similar, and what other parts, if any might be bad in this scenario?

Also, where is the best place to buy replacement fuses? These are supposed to be slow-blow fuses?
 
I have a pole position upright that has an issue with the monitor at the moment, a Matsushita TM202-G. It's blowing the fuses and R809 is burning up when plugged in. I tested some of the diodes and I think that D802 and D803 might both be bad. I'm getting good voltage, 123v AC or thereabouts.

The issue started when I was working on the power supply. I took it out to do some work, and I think the ground from the monitor may not have been making a good connection when I turned it all back on.

I was wondering if anyone else has seen something similar, and what other parts, if any might be bad in this scenario?

Also, where is the best place to buy replacement fuses? These are supposed to be slow-blow fuses?

i stock about every slow blow/fast blow/axial leaded, etc. fuses. i also have cap kits and parts for this chassis if you need.
 
i stock about every slow blow/fast blow/axial leaded, etc. fuses. i also have cap kits and parts for this chassis if you need.

Thanks, I ordered some fuses and a cap kit from you. I didn't see the diodes there, so ordered them from Digikey, I'm hoping that's all that is wrong with this monitor and I can get it back up and running soon!
 
I think the ground from the monitor may not have been making a good connection when I turned it all back on.

I assume you are talking about the ground strap connected to the frame? If so, that is/was not your issue. You don't even need it for the monitor to work.
 
I assume you are talking about the ground strap connected to the frame? If so, that is/was not your issue. You don't even need it for the monitor to work.

I think the ground on the power supply might have been not making a good connection. Anyway, the monitor is burning up r809 every time. I don't know what the issue is though, I've changed out a few parts with no success, always r809 catches on fire.

:(
 
I think the ground on the power supply might have been not making a good connection. Anyway, the monitor is burning up r809 every time. I don't know what the issue is though, I've changed out a few parts with no success, always r809 catches on fire.

:(

What've you changed? There could be a bad flyback, hot, transistor etc... The list goes on.
 
please provide a list of what has been changed.

First thing, Why is R809 going up in flames. You are using a proper fusible flame proof resistor right?


I've only seen R809 fail because D802 had failed. I've only fixed that issue twice and both times a new D802 was all it took. No idea why it failed.

You say it is blowing both fuses? If F002 is blown then probably something is shorted.

Last time I had something like this D554 was bad. Just replace the HOT with something like 2sd870 or get a new D554, I don't know if i have anymore, I forget what i used. Once i realized a 2sd870 worked I just used that.
 
please provide a list of what has been changed.

I changed out R809, D802, D803 and Q802. And R808 since I accidently desoldered that thinking it was R809.

First thing, Why is R809 going up in flames. You are using a proper fusible flame proof resistor right?

Hmm, probably not, I'll look into that... I don't think what I bought is. Even if I were to get a flame proof resister, I guess there is still an issue that's causing it to go up in flames?

I've only seen R809 fail because D802 had failed. I've only fixed that issue twice and both times a new D802 was all it took. No idea why it failed.

I did replace D802, but I may not have the correct replacement part. The monitor manual says it's a TVSRM25, but I couldn't find that exact part. What would a suitable replacement be that's available?

You say it is blowing both fuses? If F002 is blown then probably something is shorted.

The last time I plugged it back in, after replacing the diodes, the fuses didn't blow (I didn't realize you needed slow-blow fuses, and I don't believe that's what was in there before I started working on it.) On the topic of fuses, I noticed that one side of the board says F001 is 4A, the other side says 3A. The manual says 4A. Some previous owner had 3A fuses in there for both F001 and F002, and they didn't look like slow-blow to me, they had a very thin wire.

Last time I had something like this D554 was bad. Just replace the HOT with something like 2sd870 or get a new D554, I don't know if i have anymore, I forget what i used. Once i realized a 2sd870 worked I just used that.

This chassis has an 2sd870 on it actually. It's possible you have worked on it, since the person I purchased it from had some work done on the boards by you. :)

Thanks for the help!
Shawn
 
Last edited:
These are the replacement parts I bought listed below. I searched around for equivalent replacements and I thought these were appropriate. Does anyone know if these will work, and if not, can you recommend appropriate replacements?

(what the manual stays -> what I bought)

D802 TVSRM25 -> 1N4001
D803 TVSRM1ZM -> 1N4757A-ND
Q802 2SC1473PNC -> 2SC1473RACT-ND
 
TVSRM25 is the zener and 1N4757A would work NOT the 1n4001

TVSRM1ZM should be a 1n4007 NOT a 1N4001. so that is not correct

the 2SC1473 is correct.

I actually had that reversed. I did have D802 as the zener and not D803. I'll try a 1N4007 for D803, and also the correct fusible, flame proof resister in R809 and see how that goes.

Thanks!
Shawn
 
The continuing saga of trying to get this monitor chassis fixed!

I've got the correct parts in for R809 and D803 now, and correct fuses now.

When I turn on the system, I have no neck glow and the large white resister, R802 the 20W 200 ohm resister gets very hot and starts smoking.

Fuses don't blow, and it looks like R809 is still intact.

Has anyone seen that, and what's the likely issue there? Does that resistor need to be replaced? Q801, the 2SD692 ?
 
I found this post regarding a very similar problem, but I don't know if the OP ever did get it figured out.

http://forums.arcade-museum.com/showpost.php?p=2581829&postcount=4

Replacing Q801 might be worth trying it sounds like. That's an 2SD692. It seems difficult to find some of these parts though. Does anyone know where to find this part on-line?

I've seen some on alibaba, just not sure of ordering anything from there.
 
I'm still trying to get this monitor working again.

At the moment it's blowing R809. I've replaced quite a few of the parts in this circuit, but still having that problem.

I've replaced:

Q801
Q802
D802
D803
R811
R809
R808
R804
R807
 
I'm going to replace the HOT (Q551) as well, just ordered some 2SD870's for that purpose.

Is there a proper way to test this part? I am getting continuity between either leg and the case, and also between both legs too.
 
Figured I'd keep documenting the fun journey of trying to fix this monitor, and on the off chance someone has seen the behaviour and what is likely the next step.

Originally the monitor blew a fuse, but it was not a slow-blow type. Replaced it with a slow-blow and then R809 blew. Replaced quite a few parts to try and fix that, but R809 kept blowing.

I have just replaced the HOT (and R809 again), plugged it in, and I did get a picture but the monitor was behaving strangely, there was neck glow, and a picture (not that great of a picture, some roll at the top and some other issues-but the game was playable and color was good.) Then the whole monitor would die, no picture, no neck glow. It did this a couple of times, intermittent picture/neck glow.

Finally, R809 blew again.

I'm wondering if the flyback is bad/going bad? And possibly it's blowing the HOT and in turn blowing R809? Are the symptoms consistent with a bad/intermittent flyback?

I may try a replacement flyback, and if that doesn't fix the monitor, call it quits and try to get some sort of replacement monitor (most seem to recommend trashing these Matsushitas anyway.) Finding a replacement doesn't seem to be easy in my area.
 
Got an Matsushita blowing F002 and was wondering if you ever resolved your horrible situation......
Thanks
Jeff
 
Back
Top Bottom