HW-8 is Microphonic and need schematic.

[DARYLE BROOKS]

Hello To all. I have aquired an HW-8 in good cosmetic condition. I made up a new 
dc power cable and fused both legs. Plugged in and turned on . Received,although poorly,connected to a triband yagi. It has exhibited a microphonic problem wherein
if you tap on the outside case it can be heard in the audio output. I removed the upper and lower cases and tapped around lightly on the main board. I had the same results. The noise is most pronounced on the largest of the three cans with
the tuning slug inside. I can isolate the two smaller shields mechanically with my fingers and tapped on the largest shield and it seems to be the center of the problem there. Also ,if you move the antenna connection ,even slightly,or touch the center connection in side the case,the same  occurs and the received signal goes up or down when the antenna connector is not touched/coupled to myself.Very minimal output on rf into a 50 ohm laod,on the order of 300 milliwatts. I have reworked some of the few poor solder connections and nothing was improved by reflowing the solder points. I don't have a schematic .Where do I look for one and where is best place to start on this. I bought this in supposed "working order" so ,I guess the old addage of a sucker is born every minute! Thanks for any help.

TNX
Daryle

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