Help with Sanyo 14" - B+ @170V and can't adjust

omac

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Help with Sanyo 14" - B+ @170V and can't adjust

Hi,

Long story short, I bought a robotron cabaret 15 years ago that only included the actual cabinet and this 14" Sanyo monitor. I recall the monitor did work back then , and I am just getting to it now after acquiring a robotron boardset. (Hobby was on hold for a while - raising kids )

First, this is a Sanyo monitor, the tube has the following id, 370ECB22, which came up as an Atari 14" monitor. Looking at the schematics, this is very close (maybe identical) to Sanyo EZ20.

When I power up the monitor, I hear the HV, but I get NO Picture. I have no heater voltage/neck glow either. Checking the B+ voltage it is 170V. I cannot adjust it despite tweaking the B+pot (VR601). The B+ should be ~105V. With the high B+, I assume it is going into HV shutdown, hence the no picture.

I am wondering if IC601 (LA5110) is bad (TR981 is good), but cannot even find a source to order one.

Any ideas on what may be wrong?

As well, I believe the original, monitor for this cabaret was 13", but this Sanyo seems to be a perfect fit but I will find out later this week, as I got my hands on a bezel. I want to restore this robotron, but haven't been able to source a local 13" monitor with shroud. If anyone has one plse PM me. But for the time being I am trying to get this monitor working.

Thanks
omac
 
first things first.

that monitor has been sitting for far to long and the caps are probably all dried up in it.

i have seen allot of sanyo's come back to life after a cap kit.

wile you have it out i would re-flow all the big resisters, flyback, diodes in the power supply section, all headers of any kind and the neck board.

i would start there and if it does not work then there are other things we can try.



Peace
Buffett
 
Thanks for the quick reply - I'll grab a cap kit from Bob and see where that gets me.

I did actually reflow the solder for the flyback, diodes, power resister and a few more places suspecting a cold solder joint, but no luck.

Thanks
omac
 
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