The AM Forum

I got everything working on the radio except Band 6.  Looking at the schematic T18 has 3 windings.  If I look at the transformer, I only see two windings.  One is fine wire and the other one is one turn of thicker wire.   Is this correct?

thanks

Tom - AB3FL

Tom,

It has been several years since I have been in that part of a SX-62 but I vaguely recall that the third winding is hidden under the larger small gauge winding.  I spent quite a bit of time dealing with this section of a SX-62 that wouldn't oscillate on band 6 because a previous owner had soaked everything with so much tuner cleaner it killed the Q and I had to resort to motor commutator cleaner to remove the cleaner/lubricant residue from the coil and trimmer cap.

It is unlikely the windings themselves are damaged so I would focus elsewhere.  Make sure the associated trimmer cap is clean because if it has leakage that will kill the Q of the oscillator coil.  If possible substitute another 7F8.  Be VERY careful, loctal tubes can be very stubborn to pull from the socket and I saw a ham nearly amputate his thumb while struggling with an octal which finally broke-it was an ugly injury.

Roger is correct about the coil and Band 6 can be a problem, all components need to be in spec in both sections of the 7F8 plus a good tube.
Push the tube in the direction of the dimple to release the lock and then pull right out.

Ive worked on several auto radios where there wasnt even any room to manuever so had to beat it out from the bottom with a wood rod and hammer ::)

Carl

Thanks!  I did find it.  It looks like it is part of the thick single loop for the secondary.  I saw a very fine wire there and connected it back on the wafer where it should go.  I turned it on and heard broadcast FM.  A little more tweaking and cleaning and it will be ready to put back together.


thanks

Tom - AB3FL