locked ICOM1300 frequency drop #transmit


Arni Hagen
 

An example: My ICOM 7300 receive frequency reads 21.074.000 MHz as does the WSJTX main screen. The added audio offset is 1,025 Hz.

The PSK reporter receives me at 21.075.025 MHz and I have no problem making contacts.

While transmitting, the ICOM and the WSJTX main screen drops to 21.073.500 MHz. Why the frequency drop?

Thank you, Arni W5SRO


Tim Dawson
 

To put your signal more in the center of the passband of the transmitter.

You would also likely see that the TX audio sent to the rig is 1525 Hz . . . .

21.074 + 1025 or 21.0735 +1525 both put you in the same place . . .

On September 4, 2022 11:44:26 AM CDT, Arni Hagen <aphagen@...> wrote:

An example: My ICOM 7300 receive frequency reads 21.074.000 MHz as does the WSJTX main screen. The added audio offset is 1,025 Hz.

The PSK reporter receives me at 21.075.025 MHz and I have no problem making contacts.

While transmitting, the ICOM and the WSJTX main screen drops to 21.073.500 MHz. Why the frequency drop?

Thank you, Arni W5SRO








--
Sent from my Android device with K-9 Mail. Please excuse my brevity.


Martin G0HDB
 

On Sun, Sep 4, 2022 at 06:10 PM, Arni Hagen wrote:

An example: My ICOM 7300 receive frequency reads 21.074.000 MHz as does the
WSJTX main screen. The added audio offset is 1,025 Hz.

The PSK reporter receives me at 21.075.025 MHz and I have no problem making
contacts.

While transmitting, the ICOM and the WSJTX main screen drops to 21.073.500
MHz. Why the frequency drop?
Arni:

See my explanation at:

https://wsjtx.groups.io/g/main/message/33991

--
Martin G0HDB


Arni Hagen
 

Thank you for the great explanation. W5SRO

-----Original Message-----
From: main@WSJTX.groups.io <main@WSJTX.groups.io> On Behalf Of Martin G0HDB
Sent: Sunday, September 4, 2022 1:38 PM
To: main@WSJTX.groups.io
Subject: Re: [WSJTX] ICOM1300 frequency drop #transmit

On Sun, Sep 4, 2022 at 06:10 PM, Arni Hagen wrote:

An example: My ICOM 7300 receive frequency reads 21.074.000 MHz as
does the WSJTX main screen. The added audio offset is 1,025 Hz.

The PSK reporter receives me at 21.075.025 MHz and I have no problem
making contacts.

While transmitting, the ICOM and the WSJTX main screen drops to
21.073.500 MHz. Why the frequency drop?
Arni:

See my explanation at:

https://wsjtx.groups.io/g/main/message/33991

--
Martin G0HDB