MMSTV Setup

 

 As you can see I have four Virtual Com Ports. Some are needed to run Power SDR other have other functions. What we need is a Com Port to tell the Flex to key a Ptt Line. From Power SDR Cat Control I have chosen Com9. From the setup for com Ports the Pair is Com8 and Com9. Now with MMSTV we us the opposite Com Port and that we use is Com8. See picture from MMSTV setup.

Next we need a pair of Virtual Audio Ports. See SDR setup Audio VAC1 setup the way I have it also from MMSTV From MISC pull down set the Sound Card, In and out Audio Cables at bottom of screen tick ok.

Close down MMSTV

Make sure the rig is in DIGU mode.

Reload MMSTV  20 meter frequency is 14.230 and 14.233

To adjust sound card tune radio to WWV from the above picture

lower left side tick on the Adj box

SLANTED IMAGE

Clock calibration

In SSTV, the discrimination of the clock appears as a slanted image. For MMSSTV, you are not required to have the absolute and exact clock frequency value (e.g. 11025Hz). But it is important to get MMSSTV informed on what the frequency of your soundcard has. In normal situations, you would only have to adjust the slant by using the Sync window. If you want to calibrate your soundcard very accurately, listen to the standard radio or fax wave.

1) Go Option, Setup, Misc page, and push Adj button.

2) Receive standard radio wave (e.g., WWV and JJY).

2a) I found a full list of stations to tune into HERE or copy and past: http://www.smeter.net/stations/hf-time-frequency.php

3) Tune into the tick sound.

4) Continue listening to the sound for a while. You have a vertical line.

5) Click the upper point of the line.

6) Click the lower point of the line.

You could use FAX broadcasting instead of WWV or JJY, but be sure it has exact timing. Refer to the MMTTY help for details. If your soundcard seems to have different clock sampling frequencies for TX and RX, adjust the offset frequency with the following procedure.

1) Adjust the slant in RX.

2) Go Option, Setup, and TX page. Select External in the Loopback.

3) Connect the Line-out to the Line-in of your soundcard.

4) Transmit an image with Martin 1.

5) You should have an image through the external feedback.

6) After completing the image receive, go Sync page and adjust the slant. - You could use the High-accuracy slant adjustment. - Do not push the Mem button

7) Push the TX(TX offset) button in the sync page.

8) Make sure that you have no slant in the TX. If you still have slant, repeat from (6).

It is a good idea to use the High-accuracy slant adjustment at Step 6. If you are not satisfied with the result, start it again. Never push the Mem button at this step. You can use the LoopBack function of a mixer program instead of using the external feedback line. Although this procedure can be applied only for the soundcard that supports the full-duplex mode, the soundcard that does not support the full-duplex mode should not have different frequencies for TX and RX, and therefore you do not need this calibration. If you have a report that your TX image is greatly slanted, try changing the soundcard modes, monaural or stereo (Source in the Misc window of Setup MMSSTV). Some soundcards seem to use different sampling frequencies for the full-duplex and no-full- duplex operations. In such a case, the offset calibration using the external loop back does not help. You should always have the loop back External or consult the QSO report.

      

 

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