[OZAPRS] Bad signal on 30m

[Terry Neumann]

Norm McMillan wrote:

<snipping as necessary>----------


I have had this thought in the back of what passes for my mind for a
couple of days (Its 41degC here and the mind is a little rubbery!!!) Terry
did you stick with the DB9 connectors or use something smaller? (Mini
Din???) 


I stayed with the DB9's.  I like them.   They are mounted on the diecast
box, the TT3 is an "island"  in the case,  so conecting leads of some sort
were needed anyway.   It seemed convenient as well as prudent to use rf
chokes in this application where it could be helpful.   I also fitted
another DB9 to the case to allow the GPS signal to also go to a Rob
Keskull data logger.  




Beats me you didn't weld up a plate steel box out of an old square water
tank ;) 

Ah but I'm just a little more sophisticated than your average cocky ;-)
(well sometimes)     I've even given away using the 8oz  soldering iron
with blowlamp for PCB work.   (I never ever used bakers soldering flux
either)  8-)  

Welded steel plate is good for other things though.  See
http://www.rbe.net.au/~tfn/Amateur/AR_Ex.html
<http://www.rbe.net.au/%7Etfn/Amateur/AR_Ex.html> 



Is there any merit in using rf chokes as opposed to using resistors, or
vice versa?? 



RF chokes will have a lower DC resistance. 
Resistors will carry a larger current before the smoke escapes. 
RF chokes will form a resonant cct with the bypass capacitor. 
Resistors will likewise form an RC timing network at some frequency. 
RF chokes are around $0.70 ea, Resistors around $0.03. 
Guess the last line gets it! 


Thanks for that Norm.   I had five bob each way.  Resistors were used to
decouple the GPS and data logger input /outputs.

73
Terry
VK5ATN  

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