Hi Art,
I do not know for sure but I presume all of todays antenna analyzers
measure SWR and absolute impedance value (mag Z). From these numbers they
calculate the vector data (real and imaginary part of Z)
I talked to AEA last week and they announced a true vector impedance
analyzer. Seems like the will be releasing it around end of this year for a
street price "under 2000 US$" (thats what they said.)
73s Con DF4SA
At 23:49 19.07.02 -0400, you wrote:
>Hi;
>
>As I am still going back and forth between MFJ269 and VA-1 when
>contemplating my next ant. anal. purchase, here are some questions to
>those of you who know the answers... .
>I am posting those questions here as I tend not to rely too heavily on
>whatever I hear from the selling party... .
>
>1. VA-1
>Autek claims the VA-1 measures impedance up to 1000 ohms. Is it the
>impedance as present at the input terminal or measured through
>calculations involving known feedline impedance + other parameters ?
>What is the resolution of their A/D converter ?
>Has anyone verified the measurements with known networks hooked up to
>the analyser ?
>
>2. MFJ269
>Does this instrument sense the sign of the X ? . What type of bridge is
>utilized here ?.
>Since there are some preset line impedance values I presume I cannot
>measure an impedance of an unknown (link coupled) LCR network ...
>unless I'd first terminate the coupling line with the known impedance
>etc etc.
>>From other correspondence I know this thing is darn accurate and not far
>away from the HP Vector analyser within it's capabilities but how stable
>(time) are those readings ?
>
>I must admit I like the 269 due to its ruggedness but I'd like to have
>an instrument that's capable of performing also other RF tasks around
>the shack and finally be able to MEASURE at least some of those unknown
>impedances/couplings that exist under the chassis...
>
>I'd appreciate your comments vy much.
>Thanks,
>73 Art VE3PND
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