[amsat-bb] SuitSat, Any Kenwood TH-K2 Experts?

[MM <ka1rrw@xxxxxxxxx>]

ISS Amateur Radio Status: February 17, 2006

Topics:

Any Kenwood TH-K2 Experts out there?

By Miles Mann WF1F,

MAREX-MG News   www.marexmg.org
Manned Amateur Radio Experiment

Are there any Kenwood TH-K2 experts out there that
could offer some insight as why the SuitSat
transmitter may be running at 1-10 Milliwatts ERP?

The SutitSat project is supposed to be running at
setting of 500 Milliwatts.  A problem occurred that
caused the power to drop down to the 1 to 10 milliwatt
(ERP) range.  There are few theories, one could be an
antenna feed link problem or it could be a component
failure on the TH-K2.

The component failure theory is supported by the fact
that SuitSat is running longer than expected. 

(Information courtesy of ARISS)
 The original time formula came out to 9 days. 
SuitSat has been running for over 14 days and the
batteries are still over 26.3 volts.
Battery total 45ah  / 0.2 amps = 225 hours or 9.9
days. Adjusted for 50% duty cycle
Assuming 0.079 RX , converter and controller loads
TX load 0.33 amps TX 500 ma.

If the TH-K2 is “Using” less power, then SuitSat will
run longer.
Here is my “Guess”.
The 50% duty cycle of SuitSat may have dropped from
0.2 amps to 0.1 amps.
45ah / 0.1 = 450 hours or 18.75 days.


Suit Sat could still be running February 22, 2006.

What’s your Guess

The questions posted to the TH-K2 Experts:

Is it  possible for a component to fail on the TH-K2
that would result in a TX output of approximately 1 to
10 milliwatts. 

Which components would cause such a problem.

Would the Current draw be reduce with a component
failure and if so, how much less power would be used.





ARISS SuitSat Details
http://www.amsat.org/amsat-new/articles/BauerSuitsat/index.php

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73 Miles WF1F MAREX-MG

Until we meet again
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