Kenwood TS-120S Repair
August 2015

I bought a Kenwood TS-120S from ebay with a low receive problem. I could hear some signals
but the S-meter barely moved. A search on the web indicated a common problem with this
model and similar models (TS-520) as being an open T1 antenna input coil. The Kenwood
replacement part # L34-0696-35 was long since obsolete and unavailable.

I used a multimeter to confirm that one side of this transformer was indeed open. Based
on information at the K4EAA Kenwood hybrids site, I decided to attempt to rewind the 
transformer. I desoldered the part from the board and carefully disassembled the can.

I unwound the old wires counting the turns ratio as 15:70.

I then carefully rewound the transformer on the original miniature core using 42 AWG 
enameled wire and the same turns ratio.

I lightly sanded the enameled wire before soldering where I had wrapped it a few times around 
the legs of the coil form. 

Checked continuity with the multimeter and re-installed/soldered the part into the radio.

Signals were back to S9+ on the S-meter and I used the radio for several months in my vehicle,
mostly on 40 meters.