[Collins] KWM-2

[J.Wittmann]

J. Wittmann   Ahornallee 86  D33330 Guetersloh                              
Germany                                                                         
Fone:00495241-38737                                                  
Fax :00495241-39893  
Email:jwguetersloh@t-online.de
----------------------------------------------------------July,07.,2002   
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Hello  OM`s !                                                                   
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Ref.: KWM-2
Here: Tone oscillator
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I�m doing maintenance to a KWM-2. For foll. >problem< I need an advice  
from someone who is trust to this TRX. 
For side-tone-monitoring a phase-shift oscillator is used during CW. This osc. 
operates in LOCK, TUNE and CW chosen by the EMISSION-SWITCH.   
First I thought that this tone is feeded in the tx-audio-stages only during 
keying the tx (CW). So it is used with other transmitters. But this tone even is 
active during receive. The tone is disturbing weak rx-signals. And in the moment 
I haven`t find out HOW this tone is feed in the audio-stage V16. Plugging out 
V15 (Prod.-Det.) the tone still is to be heard. That means : the tone is feeded 
only in the audio-output-amp V16. But why in rx-operation ? The tone in addition 
is disturbing 
quiet moments (af-gain ccw. !) for instance in stdby. Keying the tx, the 
tone-osc. (V2b) is producing a normal side-tone. My question :      
--have I to accept this operation-situation ?
or 
--what can I do to eleminate this disturbing tone ?                             
--and how is this tone feeded in the audio-output-stage V16 ?             
The feeding-route via R155 is normal. 
Please inform me : contacts see above . Thanks !       
Regards (73)                           
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Jochen (SWL)