November 3, 1969

SB-110						Bulletin No:
Solid State Transceiver				SB-110-1

		              Audio Oscillation On CW

Problem:     	Audio Oscillation in Cw Mode with Sidetone Level
Control full on.
Symptoms:	Hand capacity affects near audio output state V6.  The large stand-up 20 ufd electrolytic capacitor C658, when moved, appears to have intermittent connection as well as
excessive heating of tube V6.
Cause:		B+ applied to VOX amplifier V4B, going through resistor	network of R49 [3.3 meg], sidetone level control
[500K], and R64 [3.3 meg] to grid of audio output amplifier V6B. 
This puts approximately +3 VDC on grid of V6B causing instabilityand 		excessive plate current flow of this stage.
Remedy:		Remove resistor R49 [3.3 meg] from receiver IF circuit board [PN 85-115] (See page 147, Fig. 3-2) and replace with a
500 pF disc ceramic capacitor [PN 21-13].

Change Notice and marked up Manual will be forwarded to Manual Department for insert so that future kit production will reflect above 
changes.

Thats everything I hold up to 1989 that covers the SB-110.  Enjoy!


73 de Joe  W7LPF/4  [NNN0KUU]
QWCA - SOWP - NCVA - FISTS - RCC Gordonsville, Va 22942 [Orange Co]

