I just went to www.mfjenterprises.com and read the pdf manual for the
MFJ-596B. The sign of the imaginary part is not sensed but you can
determine it.
A bit of the circuitry is explained.
Chris opr VE7HCB
At 10:47 PM 2002-07-20 +0200, corneliuspaul@gmx.net wrote:
>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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>Call 888-333-9041 to place your order, mention you saw this ad and take an
>additional 5 percent off
>any weather station price.
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