Thread: Johnson Matchbox 250-24 VSWR Bridge Head
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Old February 24th 07, 08:31 PM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
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Default Johnson Matchbox 250-24 VSWR Bridge Head
"harry" wrote in news:1172334927.954451.290220
@q2g2000cwa.googlegroups.com:

I have recently purchased two different VSWR Bridges.

One was made by Johnson.

The second is a clone.

Both use a fifty ohm resistor in series with the signal path. This
strikes me as a lossy setup. Is there a theory of operation posted or
a text which can explain the operation of the bridge?

The bridge is indeed a simple bridge with a single null indicator. It is
for use with less than 1W of RF, and is not intended to be left inline.

ftp://bama.sbc.edu/downloads/johnson/250-24/

Owen
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