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QCX Displayed Frequency vs CW Offset #qcx #manual

Dan Pflugrath
 

Is the upper left displayed frequency  A)  during receive mode  the transmit frequency or B) is it the transmit frequency netted with the offset frequency in the receive mode.  I thought the displayed frequency should always be the transmit frequency as in A. The manual indicates the cw offset is automatically applied or netted as in B.

I have adjusted the audio filter to center on 600 Hz.  The VFO CW offset is set to 600 Hz and the Keyer CW tone offset frequency is set to 600 Hz.  The audio alignment frequencies were also set accordingly. 

Using the Reverse Beacon Network to verify my transmit frequency when I adjust the display to 14.050000 the transmitted signal is at 14.050600.  Is this correct and  what I should expect or do I have something wrong in the setup?  
Dan KA7GPP    

K2DB Paul Mackanos
 

It sounds like it is correct

On Wed, Dec 18, 2019 at 1:19 AM Dan Pflugrath <dpflugrath@...> wrote:
Is the upper left displayed frequency  A)  during receive mode  the transmit frequency or B) is it the transmit frequency netted with the offset frequency in the receive mode.  I thought the displayed frequency should always be the transmit frequency as in A. The manual indicates the cw offset is automatically applied or netted as in B.

I have adjusted the audio filter to center on 600 Hz.  The VFO CW offset is set to 600 Hz and the Keyer CW tone offset frequency is set to 600 Hz.  The audio alignment frequencies were also set accordingly. 

Using the Reverse Beacon Network to verify my transmit frequency when I adjust the display to 14.050000 the transmitted signal is at 14.050600.  Is this correct and  what I should expect or do I have something wrong in the setup?  
Dan KA7GPP    

Hans Summers
 

Hi Dan

The displayed frequencies are always the actual transmitted frequency. 

During receive operation, the 700Hz offset (or however you configured it) and the RIT are added to the displayed frequency, and the result is the actual frequency the synthesizer is set to. This is correct convention. 

If your display reads one thing but your transmitted frequency is different, then the next question is, have you calibrated the reference frequency? 

73 Hans G0UPL

On Wed, Dec 18, 2019 at 9:19 AM Dan Pflugrath <dpflugrath@...> wrote:
Is the upper left displayed frequency  A)  during receive mode  the transmit frequency or B) is it the transmit frequency netted with the offset frequency in the receive mode.  I thought the displayed frequency should always be the transmit frequency as in A. The manual indicates the cw offset is automatically applied or netted as in B.

I have adjusted the audio filter to center on 600 Hz.  The VFO CW offset is set to 600 Hz and the Keyer CW tone offset frequency is set to 600 Hz.  The audio alignment frequencies were also set accordingly. 

Using the Reverse Beacon Network to verify my transmit frequency when I adjust the display to 14.050000 the transmitted signal is at 14.050600.  Is this correct and  what I should expect or do I have something wrong in the setup?  
Dan KA7GPP    

_Dave_AD0B
 

How I calibrated my qcx 40 was to listen to 7.0475 and compare both sidebands I adjusted the frequency calibration until I got the tone the same by ear on both upper and lower sides.

Although not true laboratory grade I figured that the ARRL transmitter was as reliably close. as anyone.  
--
73
Dave
k0mbt
Ham_Made_Keys

Dan Pflugrath
 

Hans,
Yes my calibration was off my by offset frequency of 600 Hz.  For me it is hard to make the adjustment by zero beat so I used my FT450 as a standard and set both radios to the same frequency.  I then adjusted the QCX to give the same CW note tone on both radios where I can hear the beat frequency between both radios.  This allowed me to get real close.  I checked the RBN and found that with the RBN resolution I am right on as you described with display now showing the transmit frequency on receive.  Checked it out with a contact between here in Seattle to Denver 1,000 miles with a 559 report.  Still one more check as described by Dave k0mbt below to verify the same CW note when switching from CW to CW-R.  
Thanks  73 Dan KA7GPP