Hey fellas
I've owned this Astro City for about 10 years. In the last year or so, the monitor has developed an issue where it will power off while the cab is on. The issue went from being very occasional, to every use.
Now, the monitor won't stay on for more than 10 minutes, and that's only after it has been off for a while. It's more like 10 seconds between short power cycles.
Here is what I have done so far:
Changed all caps except the 3 large filter caps
Reflowed the connector on the neckboard
Swapped power supplies with another known good PSU
Beyond caps I am stumped. The monitor looks beautiful while it's powered on! Any ideas on what I can check?
Nanao MS8-29FSG Monitor Shutdown After a Few Mins...
- JAMMArob
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Nanao MS8-29FSG Monitor Shutdown After a Few Mins...
Last edited by JAMMArob on August 14th, 2016, 4:12 am, edited 1 time in total.
- JAMMArob
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Re: Nanao MS8 (Astro City) Monitor Shutdown After a Few Mins...
A few people have suggested adjusting the B+ voltage. I'm not too familiar with this process, or if it's even a good idea!
- grantspain
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Re: Nanao MS8 (Astro City) Monitor Shutdown After a Few Mins...
sounds like caps or bad solder but thats already all been done
b+ should be 94v,test at fuse 902 and a cap ground
b+ should be 94v,test at fuse 902 and a cap ground
- JAMMArob
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Re: Nanao MS8 (Astro City) Monitor Shutdown After a Few Mins...
Thanks grantspain. I measured DC voltage at a capacitor near the fuse (measured continuity to be certain the trace is in circuit). It's reading a fairly stable 93V before and after shutdown
Last edited by JAMMArob on August 14th, 2016, 3:33 am, edited 1 time in total.
- JAMMArob
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Re: Nanao MS8 (Astro City) Monitor Shutdown After a Few Mins...
Thoughts on changing out one (or all three) of the caps in the B+ section? Specifically C906, C905, C909
Last edited by JAMMArob on August 14th, 2016, 4:00 am, edited 2 times in total.
- PrincessPrinPrin
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Re: Nanao MS8 (Astro City) Monitor Shutdown After a Few Mins...
Considering the B+ is a DC voltage I would say you're not.JAMMArob wrote:Am I measuring this accurately?
- JAMMArob
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Re: Nanao MS8 (Astro City) Monitor Shutdown After a Few Mins...
Derp. I thought it was AC for some reason. I'm just trying not to die while working on it.
- JAMMArob
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Re: Nanao MS8-29FSG Monitor Shutdown After a Few Mins...
I think i'll send this guy off to the pros!