2 ENJOYING APRS (by BOB BRUNINGA, WB4APR)
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2.8 Facebook on APRS
Purely as an aside, you can think back to the KENWOOD VC-H1
handheld SSTV device as an attempt (before its time) to add the
visual aspect of social networking to ham radio and APRS.
This was a fantastic idea. And it was fully integrated into all
KENWOOD APRS radios at the time, adding real-time video to
APRS digital and texting connectivity. You could think of the
combination as real-time “Facebook” on APRS.
Unfortunately it was ahead of its time and the VC-H1 handheld is
no longer in production, but thousands of hams have them and
still use them. These SSTV handhelds along with readily
available free SSTV software make a great visual adjunct to
APRS which could pass through any voice channel or repeater.
This was in the early 2000 time frame before anyone had camera
phones. Think of the potential.
The concept was to snap an image, and send it into APRS
where it was picked up by a web site that cataloged it by position,
originator and a text description for viewing by anyone.
This can be a tremendous asset for ham radio public service.
There are a few such active links from APRS and SSTV to the
web called the Automatic Picture Relay Network, or APRN.
Although most hams do not have the KENWOOD VC-H1, there has been a revolution in
smart phones and now anyone anywhere can use their smart phone to send and receive
SSTV images simply via the camera in the phone and an SSTV application software that
can then convert the image to tones and transmit it over any of the KENWOOD handheld or
mobile radios. Similarly, any such phone with the SSTV application can use the phone to
decode the audio and display the SSTV image. Thus, anyone with a smart phone and a
2-way radio and a radio voice channel can still send images by amateur radio!
Refer to: http://aprs.org/aprn.html
2.9 APRS Voice Alert
Three things dramatically brought back human connectivity to APRS. The first factor was
Voice Alert. The second was the addition of a frequency field in all APRS position packets.
And the third was the emergence of VOIP Internet/ham radio linked voice.
Voice alert is like a 3rd simultaneous radio channel on the KENWOOD APRS transceivers. It
acts like an intercom channel for all APRS operators to be able to quickly raise another
nearby APRS voice alert station by a simple direct voice call. It required no new hardware or
software. It simply consists of setting CTCSS 100 Hz on the APRS data channel and
keeping the speaker volume up. This way, all packet noise was completely muted, but the
operator could still be called at any time with a CTCSS 100 Hz voice call. A secondary
benefit to this technique was a free proximity detector. If any other Voice Alert station got
within simplex range (maybe 5 miles or less in a mobile) his periodic packets would give an
audible alert. These new features of APRS Voice Alert as indicated in the APRS Mobile
information Exchange drawing above finally made it easy to keep the eyes on the road, but
never miss the opportunity for human contact with a fellow APRS operator on the open road.
Voice Alert is easiest enabled and disabled by simply storing two separate Memory channels
on the national APRS frequency. One with CTCSS 100 and the other without.
