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Successful AO-51 digipeat



Finally made the time to check out the AO-51 digipeat operation again.

I successfully got a number of packets through the satellite.  I used Mike's
TlmECHO telemetry program to view the downlink, as I have found this to give
the best visual results, plus it logs the data.

Uplink TM-D700A, using 10W into a 70cm J-pole, fixed frequency transmit.  I
ran the D700 in packet mode with a laptop attached so I could type messages.
I got both beacon and keyboard messages through the satellite  (sample below
from the TlmECHO .cra file)

Downlink - small 10 element, 70cm yagi (Diamond A430S10), preamp at the
antenna(Landwehr), fixed elevation (25 deg), azimuth control, MFJ1270 with
9600 modem board, FT-847, TlmECHO software for decoding, display and logging,
KCT card, WiSP for rotor control and WiSAT(SatPC32) for Doppler tuning

Notes:
(a) this is 9600 bps packet, a very weak signal (300mW at the satellite) so
you must present your modem with a signal above the noise.
(b) Just because the DCD led comes on does not mean that you can sucessfully
decode the data (as I have observed many,many times).  I know others have been
able to use the TH-D7A and TM-D700A to digi and receive their packets, I
haven't had as good a success receiving.  I get a few packets, but not as many
as with the downlink described above.  This is something I want to work on.
(c) use PACB-1 as your via,    All,  APRS, other station callsign or most
anything for the TO:  (All will work well if an igate picks up the packet).
You can have a keyboard to keyboard conversation using All with out having to
change your TO:
Do not try to Connect to the other station.
(d) no unattended operation
(e) better performance 4 to 5 minutes after AO-51 comes up in North America,
as the usual digital stations are updating directories and
uploading/downloading files
(f) regardless of what I use as my SSID, it gets a -11 and the TO gets a -48
(g) in the LSTAT line (first line in example below)  when d:1, the digipeat
function is active;  if D:0 it is off

This is a fun, challenge - hope to see some more activity soon.
Gould, WA4SXM


excerpt from TlmECHO log file  AO-51 9600 bps digipeat data:

PACB-1    > LSTAT-0  :I P:0x13A8 o:0 l:27780 f:27817, d:1 st:6 e:01
7/10/06 11:36:45 AM
WA4SXM-11 > APRS-48  :?"@@Ń­digi testing
7/10/06 11:36:46 AM
PACBLS-8  > PACBLS-8 :PACBLS S Meter = 0
7/10/06 11:36:47 AM
PECHO-11  > PBLIST-0 :PB: Empty.
7/10/06 11:36:53 AM
PECHO-11  > PBLIST-0 :PB: Empty.
7/10/06 11:36:54 AM
PACB-1    > TLMI-1   :<binary tlm>
7/10/06 11:36:54 AM
PACB-1    > TLMS-1   :C0:0D C1:44 C2:76 C3:6F C4:04
7/10/06 11:36:54 AM
PACB-1    > BCR-1    :BCR: batv=1383 bati=162 batsense=48 battop=1383
batlow=1383 batstate=0 sav=1241 sai=592
7/10/06 11:36:54 AM
PACB-1    > LSTAT-0  :I P:0x13A8 o:0 l:27780 f:27817, d:1 st:6 e:01
7/10/06 11:36:55 AM
WA4SXM-11 > APRS-48  :?"@@Ń­Good fortune in 2006 from AO-51
7/10/06 11:37:12 AM
PACB-1    > TIME-1   :PHT: uptime is 111/12:19:39.  Time is Mon Jul 10
15:37:38 2006
----
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