[Drake] TR7 rf on Audio

[KG4LRU at aol.com]

  Just up date  the info many thanks for the sugestions . Just to clarify the 
problems! 

The tr7 is grounded both ps7 and rig and tested with without ground 
connected, antenna system is 3 ele yagi swr 1:1 , also tested on dummy load with no 
changes RF is only present on ssb mode and does not go away with the Mic gain 
Turned Down and does increase in distoration with more gain. 4 diffrent Mic have 
been tryied on the rig with no differences in problem. I have checked the 
sheilding on the boards and routing of the cable.   


Gary w8pu SUGGESTED I  TRY REPLACING THE C314 on theTrans exciter board from 
his previous experennce with a very similar problem this is aTantiuim .22 cap 
35 Volt . which I will try. Any other suggestions? 


Hello to the group I have 7400 serial number TR7 with all filters NB7 and 
home made aux board, I hooked up shure 444 Mic in fact two of them. Both Mics or 
getting RF on air results is slight raspiness Mic Gain is down so light only 
comes on at faintly on Peaks as you move it up 9/10 position it gets worse. I 
also can here it on the internal speaker and the external speaker.

Any clues were to start?  Both the PS7 and the rig our grounded.

Phil AI4dq