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Old September 21st 06, 08:44 PM posted to rec.radio.cb
Jan Panteltje Jan Panteltje is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 54
Default Amp Design Concept -- Preliminary

On a sunny day (21 Sep 2006 10:55:07 -0700) it happened "Telstar Electronics"
wrote in
om:

Jan Panteltje wrote:
SWR bridge, could be done with PCB tracks for 27MHz,
I opened my Pan SWR / power meter, and it has a zig-zag going PCB track
from RF in to RF out, and on each side of these a second track as in the above
link.
So the 2 tracks form a transformer with the main track.
No extra parts other then the diodes resistors and caps...
You can also feed the diode outputs into the analog input of a PIC,
and also the temp sensor, battery voltage, and rectified input voltage,
then you have in power, out power, SWR, and temperature to play with.
In the case of the micro (PIC) you can use one with EEPROM and calibrate
with a 50 Ohm dummyload for power.
No trimpots. The SWR is a ratio, can be done in software.
A PIC is almost cheaper then a trimpot these days...
All this should give you the picture how to do a SWR on a PCB.


You're right... it could be done on the PCB. The main advantages with
the wireline are a great way of saving board space and is fully
shielded. Their performance is predictable, repeatable, and would avoid
some iterations of PCB layout I think. I have used them in the past
with excellent results.

www.telstar-electronics.com


Sure, was just trying to up you profit $ by not buying into alien tech.