[amsat-bb] TH-D7 Event Scoring and Messaging

Robert Bruninga bruninga at usna.edu
Mon Jan 28 16:22:39 PST 2008

Reason for this cross-post is due to the large number of AMSAT
folks who have TH-D7's and TM-D700 radios and are maybe not
using them to their full potential for HAM radio... Especially
in light of our
New interest in EmComm...

Had another great Scout Event using TH-D7's for troop score

There were 17 event stations and 50 scout troops.  We were able
to field over half of the stations with D7's for score data
entry (10).  In an afterthought, we could have done at least 3
more stations for a total of 13 with data entry if we had
thought about the D700's also parked nearby.

Using the D7's for score entry substantially reduced voice
traffic and transcription errors, and repeats, while providing
error free Troop scores to the HQ tent.  See

The 2008 photos are at the end.

Too many people ignore the message and data distribution aspect
of these radios.  Not only did the D7 data entry stations not
have to busy up the 146.43 voice net, but we operated on 445.925
with our data to avoid any QRM to the 2m voice traffic -AND- we
could also chat on the same UHF channel for data coordination.

Further, every D7 operator could be tracked on the main APRS map
back at HQ as operators moved around the event -BUT- without the
encumberance of any GPS's, wires, laptops or fussy cables.  We
prepared a LAT/LON grid on the event map, and every location in
the entire square mile venue could be entered on the D7 by just
pressing the POS key and dialing in the last 2 hundredths digit
of LAT or LONG.  These were "scouts" and dads by the way, who
should know how to look at a map and estimate their position
from the grid.

To make that even easier, we prepared the four XX/YY digits for
each of the 17 event stations in advance, so that if an operator
changed locations, he only had to adjust those 4 digits to
update his position.

RESULTS:  It worked great!  Net control could leisurely look at
the incoming scores on the D700 control panel mounted to his
clipboard, and pass them to the score keepers.  The contrast
with Voice reporting is that each voice report, interrupts the
netcon's chain of thought and the voice net everywhere, and
demands immediate attention, while with the data messages, they
arrive in the background, and can be viewed by Netcon at HIS

Even the newly trained D7 HT operators said it was great (after
they got the hang of it).  Of the 10 D7 operators, only 4 had
ever used a D7 before.  Training was 5 minutes on the spot when
they were handed a D7 and a gouge sheet.


1) Don't plan on the NETCON with the D700 on his clipboard at HQ
trying to use it also as his voice rig...  Everytime he might
decide to read some messages, a voice call might come in, and
the PTT bumps him off the message screen.

2) Don't assume the battery on your 10 year old D7 is any good.
Yours truely showed up with 5 overnight-charged D7's, but two of
them were dead in the first 15 minutes.

3) The few other ops that had D7's also had D700's in their
cars.  We should have realized that the D700's could just as
easily been used for data entry at those stations, thus freeing
up their D7's for use elsewhere.  Score reporting is only a
one-time event every 45 minutes.  Easy enough to walk over to
the car and enter the data on the Mic Keys.

4) The D7 is ideal for this application.  Operating dual band,
it was able to do both the 146.43 voice net and the 445 APRS
data net at the same time.  But to save power, either band could
be toggled off when not needed with one press of the DUAL key.
Or both could be on for voice but the TNC toggled off between

5) Too many owners of D700's and D7's I fear are not practiced
and ready to send, receive and edit messages and data.  These
radios (and APRS) are much more than just vehicle tracking!


Sorry for the cross post, but we have had the D7 radio now for
10 years and it is the hottest selling Kenwood HT, yet I
continuously find operators that are not prepared to use it to
send messages, email, objects, alerts, bulletins and
announcements locally and anywhere in the world from the palm of
their hand.

If AMSAT is going to take on an EmComm responsibility, we need
to practice with what we have now...

Along that vein, also see the Satellite Simulated Emergeny Test
web page:



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