Nanao ms8 29 monitor shuts down

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MostroVeneno
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Nanao ms8 29 monitor shuts down

Post by MostroVeneno »

Hi my friends,
I wanted to ask, my astro city monitor shuts down after 2 secs and an audible click. I measured at f902 the right voltage, one probe to the fuse and one to the frame monitor, is that right? And measured 94v, i adjusted the pot +B adj and changed, so i think the regulator is properly working. I've read this can be the HOT, i tried measuring it but i don't know if I'm doing right. I didn't desoldered and tried on diode mode if i could read 2 legs, the other being base. So....i don't really know what I'm doing but i would really like to get my first cab working. Anyone have advice about this?
Many thanks in advance!
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Re: Nanao ms8 29 monitor shuts down

Post by MostroVeneno »

Anyone can mention why would the monitor shut down if getting proper b+ voltage at f902?
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Re: Nanao ms8 29 monitor shuts down

Post by MostroVeneno »

I swapped LA7832 from another chassis, and decreased B+ adj almost to the lowest. I got this image, and strange noise...[attachment=0]20190810_210412.jpg[/attachment]
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grantspain
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Re: Nanao ms8 29 monitor shuts down

Post by grantspain »

you have no deflection and it looks like a bad yoke from the photo
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Re: Nanao ms8 29 monitor shuts down

Post by MostroVeneno »

Thanks @grantspain for the reply, where can i start to fix deflection problem ?
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Re: Nanao ms8 29 monitor shuts down

Post by grantspain »

first you check for any cracks or broken tracks on the chassis, in particular around the flyback
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