problems reviving an old SW40


moshecontra
 


Hello group.  I'm new here.  Recently came back into ham radio, and bought an old SW40 (prequel to the SW40+) on ebay.  Nicely built in a larger-than-normal (still small!) enclosure with a multi-turn mechanical drive for the tuning pot.  But, I get very weak audio from the headphone jack.  Tried both low and high impedance headphones.  Can barely hear any difference between the antenna being connected or not.  If I touch the input of U3 (the product detector) with a screwdriver I get loud noises.  Much less so with the input of U1 (the first mixer), or its output (at the top of the RFC there).  And no noise at all touching the antenna input, even at the RF gain pot.  Any ideas?  Thanks.

 

- Moshe, N1OVN in Vermont, USA

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