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Ham Radio 2000
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Ham Radio 2000.iso
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fax_sstv
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xmitrecv.txt
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1996-04-03
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3KB
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97 lines
Transmit & Receive
------------------
Transmit and Receive are controlled by the buttons in the
lower left control panel resembling:
+-----------+---+
| Xmit | A |
+-----------+---+
| Stby |
+---------------+
| Recv |
+---------------+
Transmit
--------
1. Pick the desired SSTV mode.
2. Announce verbally that you are about to send a picture.
3. Click on the Xmit button or press the "X" key.
4. The transmitter will be turned on automatically.
A progress bar will grow along the left edge of the
tuning indicator. The transmitter will be turned
off automatically when it is complete.
5. Transmission can be stopped early by holding down
the left mouse button or pressing a key on the
keyboard. The space bar is a good choice.
Alignment Tone
--------------
This sends an "alignment tone" similar to the AVT Master.
This is mostly 1500 Hz (black) with some 1200 Hz (sync)
pulses thrown in.
If you want 1200, 1500, and 2300 Hz tones, just send a
checkerboard pattern in 8 second black and white.
Standby
-------
Holding down a mouse button or pressing a key will terminate
Transmit or Receive and return to Standby mode.
Receive
-------
Start receiving by clicking on the "Recv" button or pressing
the Enter key. DO NOT wait until you hear the SSTV signal.
You will miss the beginning of the picture. Start receive
mode while people are still talking.
If the SSTV interface is connected to a receiver, you should
see little dancing lines on the right side of the Tuning
Indicator. The Tuning Indicator is described in more detail
in its own help file.
Tips:
1. You might want to first select a popular SSTV mode because
VIS decoding isn't reliable under poor conditions.
2. For best results, make sure the "Free Run" mode is selected
on the Setup menu.
3. The "Sync Squelch" option on the Setup menu is similar to
the squelch control on an FM receiver. When listening to
weak signals, turn this off. Turn it on if you only want
the system to respond to fairly good signals.
4. Often a steady carrier will cause the system to switch to
Robot 12 second color mode. This is because the VIS code for
that mode is all zeros. 12 second color is about as rare
as hen's teeth so you might want to disable detection of this
one VIS code by using the NO_12C_VIS command in the PKTV.CFG
file. This option does not prevent reception of this mode,
only automatically switching to it.
Here are some popular SSTV frequencies where you are likely to
find some activity.
3.845 3.857
7.171
14.230 14.233
21.340
28.680
145.5 MHz