This shows some SSTV pictures I sent and received on the 20.5.2004 @ 05.30 UTC
with Mike VK5CRS in Adelaide Australia.
The bottom right picture above was sent by me and returned by VK5CRS to show me how they were receiving my pictures.
The one in the middle above is a rescued bird with a wing missing, he will need to be look after for around 25 years!
Guidelines for MMSSTV Slant Adjustment (Prepared By Rick WBØVZW)
1. You have to have a known good reference station that has no problems with slant on xmit or receive.
This station is the All Seeing and All Knowing Reference Station from this point on in this explanation.
2. Now that Item #1 has been established, Lets Assume that you are the new kid on the block and that you have been receiving pictures and have adjusted the timing clock numbers to give you straight pictures on receive and now you want to transmit one. Ok go ahead and do it.
3. The Reference Station receives your picture and clicks on the sync tab and then the Smiley Face and eventually MSSTV gives him or her a correction factor to make his clock match your clock. Since this station is the defacto standard, they will not be inclined to change anything on their end. Instead, they will give you a number that represents the TX Offset value that you need to use for your Transmit. This number will actually be the opposite polarity of the number shown in their software when they ran the Smiley Face on your picture. If the Reference station tells you -1.50, go into MMSSTV Option/Setup MMSSTV/Misc tab and set this value into the TX Offset window of the Clock adjust portion of the screen. It's just that simple. You must keep in mind that the Smiley Face feature is designed to adjust the receiving stations clock to match your transmit and since the receiving station in this case, is the Reference station, they will use the Smiley Face calculated numbers to give you a transmit offset adjustment factor.
4. Again using the Reference Station as the de facto standard, this is what happens on their end when they receive your picture.
A. If your clock number is set to low they will receive your picture with the bottom shifted to the left.
B. If your clock number is set to high they will receive your picture with the bottom shifted to the right.
5. Now with reference to you receiving pictures, just the opposite will occur on your end if you are not yet receiving pictures that are straight with reference to steps 4A and B above.
A. If your clock number is set to low you will receive a picture that has the bottom shifted to the right with reference to the transmitting station.
B. If your clock number is set to high you will receive a picture that has the bottom shifted to the left with reference to the transmitting station.
There it all is in a nutshell and this is not intended to make anyone feel stupid, it is my attempt to help make it easier for all so we can spend more time transmitting and less time straightening out slants.
(Prepared By Rick WBØVZW)
Another way to adjust slant in MMSSTV suggested by Geoff G4XUG is;
Receive a reliable straight picture, then click on the SYNC tab on top of the main picture window then click on the “MEM” button near the bottom right of the sync window. This will set your sound card timing to that of the station that sent the original picture. You can check this by making a note of the number at the bottom of the picture window when in sync (11,000 something) this should change for the new timing to be effective.
Prepared By Geoff G4XUG
If you have ant tips regarding SSTV you would like to share please e-mail me.