[amsat-bb] thanks

Larry Gerhardstein gerhardstein at montana.com
Fri May 7 21:49:09 PDT 2010


I want to thank all of the good folks who helped me get my satellite 
station on the air.  This has been a process since about last fall.  We 
were gone during the winter and restarted the project when I returned 
home.  I'd like to recognize W4AS, K7WIN, PE0SAT, KB7ADL, K0VTY, N6NKF, 
Scott Hagerman (non ham), AA5PK, K6LCS, G8IFF, certainly others ... and 
most of all Erich DK1TB, author of SatPC32, who spent much time 
researching drivers, answering questions, and attempting to duplicate 
problems I have been having.

A few lessons learned... from all this.

1) Don't jump to conclusions.  My rotor control spent about 3 months at 
Yaesu service only to learn nothing wrong with it.  The technician at 
Yaesu never suggested the trouble could be fixed by optical isolation of 
the RS232 line going to the rotor control box.

2) Do not assume the nature of a RS232 cable.  Use an ohm meter and 
determine if it is good or bad, straight through or cross-over or 
null-modem.  If I had started out using the ohm meter on my cables, that 
would have saved me much time and frustration.  Both GS-232 and CI-17 
call for straight through serial cables.  I made the mistake of using 
two null modem cables; unfortunately I did not know they were not 
straight through until later when I thought to use an ohm meter.

3) Don't assume you can construct a straight through RS232 cable by 
connecting two null modem cables in series.  This may work, and it may not.

4) Before installing optical isolators in the RS232 lines, make certain 
the devices are compliant with the isolators.  I tried optical isolation 
in both the rotor control and the rig control lines.  An isolation 
device between computer and GS232 rotor interface was needed.  However, 
the CI-17 does not like them.

5) The optical isolators from CF that I used seem to have polarity.  
Make certain the female end of the isolator is against the computer's 
male connector.  Do not turn the isolator around and use sex-changers 
between computer and isolator.  This was just a random thing I tried.... 
it did not work.

6) When running into difficulty as I did, document everything.  I kept 
repeating the same trials over and over, wasting time, and about driving 
myself to madness.

7) In my opinion when using Windows 7 of Vista 64-bit, only install 
drivers designed for those systems.  Drivers for 32-bit are not reliable 
in 64-bit applications and may cause the computer to crash to blue screen.

8) Before ordering USB to serial conversion devices make certain the 
drivers that come with those gadgets are compatible with the computer 
operating system you plan to use.  Many days after I received my KeySpan 
device, I called Tripp Lite.  The sales person there told me they do not 
presently have a 64-bit driver for the USA49WG.  Wish I had known that.

9) Make sure the baud rate in the transceiver matches the baud rate 
being set up in the CAT setup menu.  If you can affort it, get a RS232 
serial data analyzer.  I downloaded the free version of 232Analyzer.  
Full version is about $140.  232Analyzer helped a lot and allowed me to 
see both data transmitted and received.  This led me to the mismatched 
baud rates in the ICOM and SatPC32.

These are the issued I stumbled on.  Different computer hardware, 
different ham gear, different operating systems may produce different 
results.  Beware of Murphy.

73, Larry W7IN

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