I don't know of any antenna analyzer that will do that. It's always been
cut-and-try for me. There are probably computer programs that will do it.
The AA-600 does display other things than SWR. It will show impedances of
the load. It has a TDR function. You could use the impedance to calculate
how much to lengthen or shorten the line.
My NanoVNA is quite versatile, but it does not work with long feedlines. I
could not get any results on a 200 ft coax feedline with the NanoVNA. I
think its power output level isn't high enough. The AA-600 does that with
no problem.
73, Zack W9SZ
On Mon, Feb 6, 2023 at 4:00 PM Barry Jacobson <bdj@alum.mit.edu> wrote:
> Hi, thanks for the info. Does the Rig Expert do whatif scenarios? If it
> makes measurements of my current setup, will it let me know the effects of
> shortening or lengthening the feedline without actually doing it?
>
> Thanks very much.
>
> Barry WA2VIU
>
> --
> Barry Jacobson
> WA2VIU
> bdj@alum.mit.edu
> @bdj_phd
>
> On Mon, Feb 6, 2023, 4:51 PM Hans Brakob <kzerohb@gmail.com> wrote:
>
>> I second the motion on *Rig Expert*. I have the AA-55 Zoom because I
>> play up through 6 meters, but the AA-35 Zoom would be fine choice if you
>> only worry about MF/HF.
>>
>> Quite versatile, easy to learn/interpret, and accurate.
>>
>> 73, de Hans, KØHB
>> “Just a Boy and his Radio”™
>> ------------------------------
>> *From:* CQ-Contest <cq-contest-bounces+kzerohb=gmail.com@contesting.com>
>> on behalf of Zack Widup <w9sz.zack@gmail.com>
>> *Sent:* Monday, February 6, 2023 7:39:42 AM
>> *To:* Barry Jacobson <bdj@alum.mit.edu>; CQ Contest <
>> cq-contest@contesting.com>
>> *Subject:* Re: [CQ-Contest] Antenna Analyzer Expert
>>
>> I highly recommend the RigExpert analyzers. I got an AA-600, which may be
>> more than you need but I do a lot of work on VHF. If you're mainly
>> interested in HF, the AA-35 ZOOM should fill your needs. I got the unit
>> with the Smith chart option. I believe you have to order these directly
>> from the RigExpert site, not from a dealer.
>>
>> 73, Zack W9SZ
>>
>> On Mon, Feb 6, 2023 at 2:41 AM Barry Jacobson <bdj@alum.mit.edu> wrote:
>>
>> > Hi, I need advice on getting one of the antenna analyzers on the
>> market. I
>> > have an 80 meter dipole fed with ladder line from an MFJ 989D tuner. I
>> > seldom use 10 meters, but tried to go on the 10-10 phone contest today.
>> > Would not tune in that segment of band. Tuner instructions say most
>> > commonly need to shorten feedline by 1/8 wavelength at band that won't
>> > tune. Before cutting line and possibly messing up other bands that work
>> > fine, I would like to know exactly where I stand on each band. I could
>> use
>> > a device that will tell me exact length of line currently, and what
>> effect
>> > shortening will have on all other bands, and whether the new impedances
>> > will be within range of capability of tuner. I don't mind learning
>> complex
>> > impedances and Smith charts if necessary, but want to do it
>> systematically.
>> > Don't know if devices out there do this for you. Some possibilities I
>> have
>> > heard of are NanoVNA, Rigexpert, MFJ antenna analyzer. I don't know if I
>> > should go on EZNEC. The last 15 feet of each end of dipole droop
>> > vertically, but don't think that's the main problem.
>> >
>> > There is a whole page of devices. Don't know where to begin.
>> >
>> > https://www.eham.net/reviews/view-category?id=31
>> >
>> > Any advice from an expert greatly appreciated.
>> >
>> > 73,
>> >
>> > Barry
>> >
>> > --
>> > Barry Jacobson
>> > WA2VIU
>> > bdj@alum.mit.edu
>> > @bdj_phd
>> > _______________________________________________
>> > CQ-Contest mailing list
>> > CQ-Contest@contesting.com
>> > http://lists.contesting.com/mailman/listinfo/cq-contest
>> >
>> _______________________________________________
>> CQ-Contest mailing list
>> CQ-Contest@contesting.com
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>>
>
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