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Main => Monitor/Video Forum => Topic started by: mahkeymike on June 13, 2014, 10:18:28 am

Title: TATUNG type66 H size not adjusting.
Post by: mahkeymike on June 13, 2014, 10:18:28 am

I posted this in the touchscreen section with very little help so decided to post here.

So anyway, I got this tatung type 66 crt im trying to fix. caps seem to be replaced not long ago as most of them look really new. The only problem i have with one of them is the horizontal size wont adjust. I had another type 66 on hand so i swapped outthe circuit boards and while i can adjust the horiziontal size on this other board, I can not get the H/V hold to stop moving. Usually i can get them tuned in pretty easy but this one i cant so im going to assume theres something faulty with this circuit board aswell.

Now what i would like to do is figure out the issue with the H size and use the parts from the spare to fix it but i dont know what parts are the culprit for a non adjustable H size. Please help if you can.

Thanks.

Title: Re: TATUNG type66 H size not adjusting.
Post by: Ken Layton on June 15, 2014, 12:04:43 am

Merit type 66 monitor (made by Tatung) could have one of the following components bad on the main board:

Q1: type 2SC458 transistor

C1: 3.3 uf @ 50 volts
C2: 1 uf @ 50 volts
C3: 100 uf @ 35 volts
C9: 4.7 uf @ 50 volts
C12: 2.2 uf @ 50 volts
C15: 100 uf @ 35 volts

IC1: type LM358

ZD1: zener diode 24 volts

I'd check Q1 first.

Title: Re: TATUNG type66 H size not adjusting.
Post by: mahkeymike on June 15, 2014, 04:47:00 pm

Thanks Ken. I will start replacing them in the order you suggested till i find the culprit.