Since last Friday's QSO wiith Eric AA4SW on TeamSpeak about the SDR's DDS
stability problem, I thought I should measure how much drift I actually
have. While doing some stabilty testing using 15mHz WWV as the reference, I
thought I might run the Tx on VFO-B on 29.0mHz AM and put 15mHz WWV on VFO-A
and run SPLIT. Then I could immediately check for drift on 15mHz (due to
heating, etc.) upon switching to receive.
This is what actually happened. When switching to Tx, the 'Transmit out
of band' msg popped up! It seems the Error msg detector thinks I'm
transmitting on VFO-A, on 15mHz on top of WWV! But SPLIT is ON! Okay,
what if we exchanged A & B, putting 29mHz AM on VFO-A and 15mHz WWV on VFO-B
and again - run SPLIT? As expected, the Rx was on 29mHz and when switching
to Tx - the SDR transmitted on 15mHz WWV, with no complaint from the
'Transmit out of band' detector!! Not cuole!!
If SPLIT is used, then VFO-B controls the Tx freq. The 'Transmit out of
band' detector must pay attention to this fact! BTW, the software used was
Beta v1.3.5.
73, Alan K2WS
