[TenTec] Problem w/Omni VI and INRAD filter

[K3BU at aol.com]

In a message dated 11/20/03 11:14:04 AM Eastern Standard Time, 
k5uj at hotmail.com writes:
>>They are wide enough to where they are right up against the carrier.  This 
makes R3 and R4 nulling adjustments critical. <<


OmniVI is BFO (and passband setting) is drifting, make sure that the 
alignments is done after rig is warmed up and stabilized. For overall rig temperature 
"management" it is perhaps best to minimize heat transfer from the finals by 
using cooling fan, this helps to even out extremes (like RX time vs. contest 
perpetual CQing). 

Seems that problem is caused by different positioning of the filter's curve 
vs. BFO frequency and greater sensitivity to suppression of the carrier by 
balancing circuit. Crystals and filters can drift with time, depends on quality of 
manufacturing.

Yuri, K3BU