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I have a NAC with a Nanao MS9, just got the cab about a week ago. The monitor came horizontal (and worked normally in this position), but I carefully rotated it to vertical with another person, making sure nothing was damaged. First powerup after rotation the chassis clicked wildly and did nothing else so I powered it off and checked to make sure everything was seated, which it seemed to be. Next powerup there was no clicking and the monitor came on, but it started up overbright (nearly white, washed out), the highest brightness kind of concentrated in a thick white line near the left side of screen (or top if in horizontal). After 10 minutes or so the picture turns out normal and looks very good actually, great sharpness and bright colors, except for some red bleed when something is very bright (which I have mostly tuned out). I figure it just needs a recap and continue to use it like this. Now yesterday after turning it on I hear clicks coming from the chassis for a few seconds but the monitor starts up as it normally does and now every time I power it up the chassis clicks a few times but other than that no change, monitor still works normally after starting very bright. Any ideas what the clicking might be and if I should order any other parts in addition to the caps?
 
Clicking sounds like a relay.... What are you connecting to the monitor?
 
sounds like the flyback. It has pots on it for voltage which also controls how bright the screen is.
 
Clicking sounds like a relay.... What are you connecting to the monitor?
Normal JAMMA PCBs, games from the 80's and 90's.


sounds like the flyback. It has pots on it for voltage which also controls how bright the screen is.
I have already tried the screen pot, and have used it in setting up the monitor to look good. Screen pot doesn't affect the startup problem.
 
Here's a picture of how this monitor looks from a cold start. It's pretty distinctive, so I'm wondering if this points to any specific problem I can troubleshoot.

OAs6YjS.jpg
 
If you boot it with no video signal connected, do you see the same behavour?
 
I would start with caps and reflowing all solder joints. You are going to want that done regardless so it's a good starting point.
 
yoke wire and coil look normal?
 
If you boot it with no video signal connected, do you see the same behavour?
No, the screen is black without any signal. This does happen no matter what board I use though.

I would start with caps and reflowing all solder joints. You are going to want that done regardless so it's a good starting point.
I have caps on the way to me and I plan to reflow, I was just wondering if this could be a symptom of something else, and if I should order any other parts.

yoke wire and coil look normal?
I wouldn't know what normal is, not enough experience with CRTs. Here are some high res pictures:

https://imgur.com/a/F5XyT
 
Depending upon the type, your monitor could be auto dual frequency 15kHz 24kHZ. The relais might switch between the 2 resolutions. I have no experience with MS9 monitor chassis, but Hantarex ones use a different B+ voltage between the 2 resolutions. The image being way to bright could be an indication of an incorrect B+ voltage. It looks like the circuit detecting the video signal frequency is failing. The fact it doesn't tick and doesn't show a white line without video signal also points into that direction. The fact it works after a small period of heatup could indicate some capacitors are on their way out. Ripple on the supply rails can disturb the frequency detecting circuit.
So, I can only confirm, start with the capkit. It might fix the issue.
 
Ms9 has no auto frequency, but a connector you have to move from on position to the other.

But a cap kit would be a good start and check/adjust B+ after that
 
Ms9 has no auto frequency, but a connector you have to move from on position to the other.

But a cap kit would be a good start and check/adjust B+ after that
Where is the B+ test point and adjustment on this monitor? I have tried searching but can't find anything
 
Ms9 has no auto frequency, but a connector you have to move from on position to the other.

But a cap kit would be a good start and check/adjust B+ after that
just a correction here, there are in fact auto switching ms9s and manual switching ms9s. I have some of each.
 
Ms9 has no auto frequency, but a connector you have to move from on position to the other.

But a cap kit would be a good start and check/adjust B+ after that
just a correction here, there are in fact auto switching ms9s and manual switching ms9s. I have some of each.
Cool, thanks for correctimg me!
Which cabs have the auto switching? Only seen the manual in NAC’s, Cyberleads etc.
 
Ms9 has no auto frequency, but a connector you have to move from on position to the other.

But a cap kit would be a good start and check/adjust B+ after that
just a correction here, there are in fact auto switching ms9s and manual switching ms9s. I have some of each.
Cool, thanks for correctimg me!Which cabs have the auto switching? Only seen the manual in NAC’s, Cyberleads etc.
I can't say for certain. I know of a few versus city cabs (and own one) and all of them have auto switching ms9s chassis. The PCBs themselves are identical, but there are a few component changes obviously. They are easy to identify auto vs manual because they have a black relay where the jumper connector is on the manual. I likely have some photos on my phone already I can upload in a bit.
 
Just checked and mine does have that relay despite being in a NAC. Unfortunately the B+ test point is inaccessible with the monitor mounted vertically, so I'll have to test it when I pull it out to recap. Where is the pot to adjust the B+?
 
Ms9 has no auto frequency, but a connector you have to move from on position to the other.

But a cap kit would be a good start and check/adjust B+ after that
just a correction here, there are in fact auto switching ms9s and manual switching ms9s. I have some of each.
Cool, thanks for correctimg me!Which cabs have the auto switching? Only seen the manual in NAC’s, Cyberleads etc.
Both of my MS9-29 chassis (one in an Astro I installed as it didn't have a chassis in it when I got it, the other was already in my Cyber Lead when I got it) are auto switching. My Astro chassis also has auto degauss

The connectors for the frequency change are still there, there's just a relay on top instead of pins and a connector :)
 
Do you happen to know the type on the MS9 PCB?
Like MS9A or MS9S?
 
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