[Heathkit] SB-102 Very little drive - Update

[Jim Shorney]

Hi Carlos,

On Mon, 6 Apr 2009 17:34:05 -0400, Carlos A. Archilla wrote:

>I discovered many off value resistors in the driver board

I hope you are using a little common sense if you are checking resistor
values in-circuit. You will often get erroneous readings from other
components in the circuit. Remember, in older gear, resistors are ofter
10% or even 20% tolerance. Carbon composition resistors can also drift
with age due to moisture absorption, and return closer to the marked
value after they are baked out. 

>If anyone knows of a different way, without taking the radio apart, please let me know.

Only replace as a last resort....?



>The low drive improved some with the resistor's change, but the real improvement came about after tightening the nut on the neutralizing capacitor mounted on the RF cage.

Check every screw in the radio, especially the ones that hold down the
circuit boards. These are ground points. Also check grounding
tabs/fingers on the coil shields.

73

-Jim


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