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Re: Return loss bridge (2.4 gHz ) report

Hi All

In the Sep/Oct 2000 AMSAT Journal pages 13 - 19 two Amateurs ( KN6KC and
VE5FP ) teamed together and produced a Bridge unit to test return-loss on
1.2 and 2.4 gHz antenna systems.    I wish to report that I have
purchased a 2.4 gHz bridge and it is an excellent device.    There is
nothing like being able to measure your 2.4 gHz antenna impedance return
loss rather than modeling  or just plain guessing about it.     It is
small, simple and easy to use.
I purchased the kit and examined it carefully .    I came to the
conclusion after making a devise to hold each component as I soldered it
to the PCB that at 72 I could not put this SMT Bridge together without
risk .      I return the kit for a completed unit.   The additional $50
that I spent was well worth the cost to me.      The completed Bridge is
pricy ( $200 ) but how pricy the knowledge that the antenna is ok can be.

I made a home brew, 20 turn Kraus helix using the  W0OQC matching system
and had very good return loss.    That W0OQC matching system is easy .   
 Much easier to build and to adjust for return loss than the Kraus (
Miller ) tapered shim ( non adjustable ) and it allows grounding of the
antenna proper to protect the sensitive Preamp devise from static
electrical build up on the antenna.     Thanks William.

Checking the dipole for return loss that comes with the TSI converter,  I
found it very good .   This surprised me some what since return loss is
effected by the dish reflectance coefficient and I expected the dipole
(not mounted on a dish) return loss would be worse.   That will cause me
to want to try it on a dish if I get the chance.

Note:   If you purchase the kit, do not handle the active elements if you
expect to return it for a completed unit.
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