[TowerTalk] TDR recommendations?

[Jim Lux]

At 08:11 PM 3/17/2007, Howard Klein wrote:
>I'm looking for recomendations for least expensive but dependable TDR's
>usable for antenna phasing. Any comments on the  Riser Bond 1205CXA or
>Tecktronix 1503 both of which are available on Ebay in the $500 range or
>other suggestions.
>Howard..K2HK


For phasing?
So, say you want 10 degree accuracy at 30 MHz.. that's a time delay 
of 33 ns/36 or about 1 ns precision.

Might be easier to use an antenna analyzer, short the end of the 
coax, and look for the dips.  A lot more precision at the expense of 
a bit more time.

Any sort of CW measurement (i.e. antenna analyzer, impedance bridge, 
etc.) is going to have a much better SNR than a pulsed measurement, 
and the inherent precision of the measurement will be better.

A TDR is real nice if you're looking for bumps in the response from 
bad connectors or crimps in the dielectric, and even then, these 
days, a good vector impedance bridge and some software to turn the 
frequency sweep into time domain would probably be a better way to do it.