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Old 05-12-2014, 07:01 PM
earlyfilm's Avatar
earlyfilm earlyfilm is offline
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Quote:
Originally Posted by radio nut View Post
Was just watching a documentary on the history of old trains and the screen is showing old film and as an the scene changes from one train to another and the background is a lot brighter it starts buzzing
OK, need a second test. Remove your antenna connection and short the set terminals while the set is buzzing. If the result is no buzz, then do the test that I proposed in the 9th post in your old thread.

http://www.videokarma.org/showthread.php?t=259882

This test did not pinpoint the problem before since there was another cause for the buzz then.

If this tests now reduces or eliminates the buzz, then the problem is signal overload.

The most obvious cause is too strong a signal.

It also can be caused by misadjustments of gain setting (including local / distant switch) or gassy tube in the tuner, IF, or sync tubes. Most Muntz sets did not use them, but if your Muntz has a tube labeled either AGC or AGC Keying, that is a real possibility. If it has keying, (and only if) then also suspect the tube that provides the signal that is keyed, which often is the video output tube.

James.
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Old 05-13-2014, 01:00 PM
radio nut's Avatar
radio nut radio nut is offline
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Join Date: Dec 2007
Location: Lima, Ohio
Posts: 836
Quote:
Originally Posted by earlyfilm View Post
OK, need a second test. Remove your antenna connection and short the set terminals while the set is buzzing. If the result is no buzz, then do the test that I proposed in the 9th post in your old thread.

http://www.videokarma.org/showthread.php?t=259882

This test did not pinpoint the problem before since there was another cause for the buzz then.

If this tests now reduces or eliminates the buzz, then the problem is signal overload.

The most obvious cause is too strong a signal.

It also can be caused by misadjustments of gain setting (including local / distant switch) or gassy tube in the tuner, IF, or sync tubes. Most Muntz sets did not use them, but if your Muntz has a tube labeled either AGC or AGC Keying, that is a real possibility. If it has keying, (and only if) then also suspect the tube that provides the signal that is keyed, which often is the video output tube.

James.
I did do that test, but I do not remember exactly the results. I THINK that all I got was snow and weak picture..... but no buzz....thanks for reminding me!
I will re test ans post results maybe this weekend.
Thank you again!
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