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Tuning eye help needed!
5/17/2001 7:37:57 AMBrad
I have a 1940s Magnavox console radio/phono. The
problem I am having is that although I am getting some
deflection, the tuning eye deflects by only a couple
of degrees. At no time does it deflect to less than a
90 degree angle. I have heard that an open resistor
can cause the shadow not to deflect. Could this be the
cause of my problem? The magic eye tube is 6U5, and
the radio and amp chassis numbers are CR188 and AMP101
respectively. Thanks in advance.
5/17/2001 9:07:42 AMNorm Leal
Hi Brad

An open resistor could cause the problem or lack of AVC voltage. There is usually a 1 meg resistor built into the socket between pins #2 and #4. It may have gone up in value. Measure resistance between these pins.

Poor alignment or weak tubes can cause low AVC voltage. Measure voltage on pin #3 with a VTVM or digital meter. This voltage will vary and should be -10 volts or more negative on a strong station. The radio may require an antenna to get the eye to deflect very far. A 6U5 requires -22 volts to close.

Norm


: I have a 1940s Magnavox console radio/phono. The
: problem I am having is that although I am getting some
: deflection, the tuning eye deflects by only a couple
: of degrees. At no time does it deflect to less than a
: 90 degree angle. I have heard that an open resistor
: can cause the shadow not to deflect. Could this be the
: cause of my problem? The magic eye tube is 6U5, and
: the radio and amp chassis numbers are CR188 and AMP101
: respectively. Thanks in advance.



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