UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - FT-101ZD sizzling sound on tune up into dummy load.

GMB · 21st Oct 2019, 11:30 am

The other thing to worry about is the preset pot that sets the PA bias voltage. If this goes open circuit (and it can) then the PA will go into overdrive.
A simple fix is to put a bigish fixed resistor to pull the bias to maximum negative if the pot fails.

21st Oct 2019, 11:30 am	#3
GMB Dekatron Join Date: Aug 2003 Location: near Reading (and sometimes Torquay) Posts: 3,093	Re: FT-101ZD sizzling sound on tune up into dummy load. The other thing to worry about is the preset pot that sets the PA bias voltage. If this goes open circuit (and it can) then the PA will go into overdrive. A simple fix is to put a bigish fixed resistor to pull the bias to maximum negative if the pot fails.