atg
Member
Hi all,
I have a 5151 monitor here which just arrived in the mail, and has visible lines on the screen which are too bright. I have tried adjusting the knob on the front as well as the pot for "SUB-BRT" on the side of the logic board. I think maybe the amplifier IC is bad or there is a dead cap in either the brightness or h-blank circuits.
I took a picture of the first time I tested it. There are some vertical blocks from something on the IBM branded MDA card, which ended up going away, but I don't have a pic of it without those.
If anyone knows where I should look (which caps to replace / check), etc., that would be great!
https://imgur.com/a/Q5uWrgL <-- here is the pic. I couldn't get it to upload to the forum
Edit: I should say, I checked the values of the pots which I had adjusted, and they seem to be in the correct range of 100K each
I have a 5151 monitor here which just arrived in the mail, and has visible lines on the screen which are too bright. I have tried adjusting the knob on the front as well as the pot for "SUB-BRT" on the side of the logic board. I think maybe the amplifier IC is bad or there is a dead cap in either the brightness or h-blank circuits.
I took a picture of the first time I tested it. There are some vertical blocks from something on the IBM branded MDA card, which ended up going away, but I don't have a pic of it without those.
If anyone knows where I should look (which caps to replace / check), etc., that would be great!
https://imgur.com/a/Q5uWrgL <-- here is the pic. I couldn't get it to upload to the forum
Edit: I should say, I checked the values of the pots which I had adjusted, and they seem to be in the correct range of 100K each
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