The Squelch Mod for GB3YW

The only modification I have made is to the receiver in order to 
improve the action of the squelch which lacked any form of hysterisis 
and was difficult to set. To do this I fitted a resistor between pins 
12 & 14 of the TK10420 IF/Detector IC. Typical values for this resistor 
range from 47K - 220K.

G4RQI, extracted from http://www.g4rqi.pwp.blueyonder.co.uk/Kyodo.html