[aprssig] Alinco DR-135TP

[Stephen H. Smith]

mckeehan at mckeehan.homeip.net wrote:
> This is some great information. I had overlooked the online manuals page on
> the Alinco website when I looked earlier. Thanks for making me look twice.
>
> If I'm reading things correctly, it looks like the DR-135TP only operates as a
> "dumb" tracker (GPS strings) without a computer connected. Am I missing
> anything?
>   

Correct!       The Alinco uses the same Tasco TNC-on-a-chip as the 
Kenwoods, but lacks the sophisticated firmware that allows the Kenwoods 
to operate as stand-alone two-way APRS terminals using the front panel 
as a display.    The Alinco is the functional equivalent of any old 
radio with an external TNC such as a KPC3+ attached.


Further, I believe (not 100% certain) that the Alinco in stand-alone 
mode only transmits the horribly inefficient raw NMEA strings as 
received from the GPS, over the air.   [ Instead of reformatting the 
lat/long data into APRS-format that would be 1/3rd the length including 
symbol codes and comments , or into Mic-E compressed format (such as the 
Kenwoods do) that is ONE-TENTH  the length. ]


The raw NMEA strings waste far more air time on busy channels to send 
the same information.   They also actually reduce the likelyhood of the 
data being successfully received.   The much longer strings have a 
higher probability of getting "stepped on" by other stations, or getting 
trashed by mobile flutter or pops of noise.  


For transmit-only tracker operation, you are FAR better off with a 
TinyTrack or OpenTrack connected to any old two-meter rig.  These 
devices not only transmit compressed formats, they also incorporate 
smart beaconing that varies the beacon rate based on how rapidly your 
position changes.







Stephen H. Smith    wa8lmf (at) aol.com
EchoLink Node:      14400    [Think bottom of the 2M band]
Home Page:          http://wa8lmf.com


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