I boughtone of those and had a friend who said he'd modify it for me as 
per the article in qst 4 or 5 years ago.  It appears to use a very 
special chip and he still hasn't built it, guess I'll scratch that 
one...
73
Butch
WA0VJR
Node 3148
Wallace, ks.


On Sat, 11 May 2013, John Miller wrote:

> The 209 will go to VHF. I have one though it's not modified, because of what
> you say I don't know anyone willing to modify it and I'm not comfortable
> doing it.
> ----- Original Message -----
> From: "Colin McDonald" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Saturday, May 11, 2013 10:07 PM
> Subject: Re: Audible SWR meters, Analyzers, and DXCC antenna
>
>
>> an antenna analyzer is a device that transmits a tiny bit of RF into an
>> antenna, and reads the reflected power, SWR and other variables depending
>> on
>> the unit.
>> You don't tune them for anything other than frequency...it doesn't go in
>> line with the radio or anything.  They are stand alone devices that
>> connect
>> directly to the antenna.
>> Usually you select the band you want to check the antenna on, and use a
>> VFO
>> style dial to tune the frequency until you ssee a dip in the SWR...or a
>> dip
>> down to 50ohms or whatever measurement you are looking at.
>> The high end ones are auto ranging and will show the min/max swr stuff as
>> required.
>>
>> So, there was one model, the MFJ 209 I think analyzer that was
>> successfully
>> modified using a freqmite CW output frequency counter, and a voltage
>> controled oscelator.
>> You turned the frequency knob with the VCO turned on and foundd the null
>> and
>> zero nulled the tone.  Then, you checked the frequency with the freq mite
>> to
>> see where the most resonant frequency occured.
>> Unfortunately, this was only possible on the MFJ 209 antenna analyzer and
>> it
>> was a pretty invasive modification.  This analyzer still goes for a couple
>> hundred bucks on the used market, and it's hard to find someone with the
>> technical expertees to install the modification properly.
>> Also, the MFJ 209 is difficult to find, and it only works for HF
>> frequencies
>> I believe.
>> With tuners and HF being more forgiving, an antenna analyzer is really
>> only
>> particularly useful for tuning VHF/UHF antennas, and mobile antennas for
>> max
>> resonance.
>> The newer MFJ 249, 259 and 269 analyzers work in a similar way to the 209,
>> but they are unable to be modified using the original plan.  These
>> analyzers
>> will do VHF on the 249, and UHF as well on the 259 and 269 units.
>> I believe I did hear that a 249 was modified, but there was something that
>> was unstable or questionable about it.
>> You also had to add more mods to the unit to switch the frequency counter
>> to
>> read VHF frequencies.
>> So, the cat has been out of the bag for a good long while with regard to
>> an
>> accessible antenna analyzer.  The issue was that an analyzer is not a
>> cheap
>> piece of equipment, the original ham who did the mods stopped, and I think
>> parts became difficult to aquire IE the freq mite.
>> Also, with the updated analyzers the original plan doesn't work, so it
>> kind
>> of fizzled.
>> I don't know anyone on list who actually had or has one of these units, or
>> if anyone had them after the initial unit was modified.
>> there are audio and text file instructions on how to do this entire mod if
>> you can find a 209, a cw or voice frequency counter and can get in and
>> make
>> all the mods.  Or, you know someone who doesn't mind putting the time and
>> expertees into it.
>> I'm not sure if the HamPod technology could somehow be used with newer
>> analyzer devices that provide a serial data output...perhaps.
>> The issue of course, is that these newer units with data output are as
>> expensive, or more so than a brand new ts590.  So not allot of people who
>> may have the technical expertees and know how, can actually aford to
>> either
>> modify their own unit, or buy one to play with.  And, again, allot of guys
>> say they'd love something like this, but if it's going to cost a grand or
>> two, they will forgo the accessibility.
>> At the end of the day, you can buy an MFJ 269 for 500 bucks and get a
>> willing set of eyes to help for that once or twice a year you actually
>> need
>> the thing.
>> How many here would pay $600 for a mostly accessible antenna analyzer?
>> Because that was about how much the MFJ209 was with the mods done to it.
>> The proof is in the pudding that no one wanted to and that is part of the
>> reason why it didn't go anywhere originally.
>>
>> I know lots  of guys would spend probably a couple hundred for something
>> that was accessible and did the trick, but even a new unmodified antenna
>> analyzer isn't cheap
>>
>> Our ham club has an MFJ269 as part of the club's equipment and any member
>> has access to it upon request for tuning mobile or vertical antennas etc.
>> So, even hams who can see the thing are unwilling to lay out allot of cash
>> for one.
>>
>> 73
>> Colin, V A6BKX
>
>