Kenwood TS-700SP antenna
to receive / transmit relay repair. 24 February 2023
Kenwood
TS-700SP radio symptom was intermittent receive when the radio was
cycled between transmit and receive. The source of the issue is
believed to be oxidisation of the RL1 antenna to receive / transmit
relay contacts on the receive side contacts.
The
RL1 relay was removed, disassembled and contacts cleaned and reinstated in the radio,
resulting in the clearing of the intermittent receiver fault.The relay contacts were cleaned with contact cleaner and gloss
paper, so as to not damage the silver coating on the contacts and also
not leave paper fibres that may interfere with the good electrical
contact.
The
RL1 relay is a miniature RF relay, SPDT, Fast Reed Switch, 12 volt, 390Ω
coil, manufactured by ATS, part number CX-1051 and difficult
to obtain now.
Figure
1. RL1 antenna to receive / transmit relay per the block diagram.
Figure
2. RL1 antenna to receive / transmit relay per the schematic
diagram.
Photo
1. RL1 antenna to receive / transmit relay
Photo
1. Relay contacts being cleaned with contact cleaner and gloss
paper.
Video
of the Kenwood TS-700SP antenna
to receive / transmit relay repair.
