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PacSat uplink problems



Roy, W0SL, has taken me to task for not describing my uplink problem
on the PacSats sufficiently. Here is what I know:

1) The TNC is going into KISS mode (three blinks of the lights on
the TINY-2). The TINY-2 has 10MHz parts in it for high-speed operation.

2) WiSP *says* that it's putting the TNC into Full Duplex

3) The downlink works marvelously, attaining up to 90% efficiency
during a pass.

4) The PacComm G3RUH modem board is generating modulation signal
that can be varied with the appropriate on-board control and is set
to 350 mV RMS per the IC-821H instructions.

5) PTT is activated by the TNC at what seem to be appropriate times
for hole fills and connection requests for uploads, althought PTT
did not work through the ACC connector on the back of the IC-821H and
had to be brought to the front panel.

6) I have varied TXDELAY in WiSP from 50 to 500 ms without effect.
It is now set to 150 ms.

7) The transmitter is putting out carrier as evidenced by the increased
current draw by the unit and the red transmit light during PTT.

8) The transmitter (uplink) frequency is correct.

9) I have tried KO-23, KO-25, and UO-22 with identical results.

10) The 144 MHz coax and antenna to be in working order since I
was able to hear my downlink from AO-10 yesterday.

11) The cable from the G3RUH board to the ACC plug seems to be fine
since I measured 350 mV on the transceiver end.

12) I have placed the IC-821H in the 9600 baud mode. This SHOULD
set up the rig to accept the modulation from the G3RUH board.

13) I DO NOT have a deviation meter or a spectrum analyzer or 
oscilloscope on-site.

14) I do have another PacSat operator, KE0FX, willing to help me
out with terrestrial tests within the Metro Area. His current 
assessment is that there is something wrong with the TNC/modem.

I presume if we can connect at 9600 baud point-to-point on 144MHz
simplex that the modem would be properly tested. However, this would
not involve KISS mode or large file transfers necessarily.

Any thoughts?

Best 73's
--Paul, WA0RSE
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