Re: 465 Display Help Needed - another thought


Stan or Patricia Griffiths <w7ni@...>
 

billw101@aol.com wrote:

AShton, yes I have heard that same thing about the 465, however after
troubleshooting I am further able to describe the problem. The
transition of the trace either falling or rising is poorly defined
and instead of one sharp edge I see almost a centimeter of blur. I
have been through the video output amplifier from one end to the
other but I still have the symptom that any capacitance such as a
scope lead hung on either vertical deflection output causes the
amplifier to go into high freq. oscillation and the trace becomes a
fog. I will press on but there is definitely something wrong with
this thing.

Bill
Hi Bill,

I would take a close look at the input FET's to make sure they are the
original type. Sometimes they will short or open and the repair techinician
will use whatever FET is handy and not bother with the correct part. This
can cause all sorts of oscillation problems and stuff like you are seeing.

Stan
w7ni@easystreet.com

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