I'd like to have the file. Thanks.
73
Butch
WA0VJR
Node 3148
Wallace, ks.
On Tue, 14 May 2013, Colin McDonald
wrote:
> the voltage regulation is done through the lm336 temperature stable voltage
> regulator and the 2n2222 transistor along with the ca3240 op amp.
>
> Even if these exact parts aren't available, clones, copies or very similar
> chips are easily available...these things are cross referenced all the time.
> Just try somewhere like digikey for the 3 IC's you need.
> If you get the right parts, the guy can't say it's impossible anymore.
>
> Butch, do you have the text file that describes the circuit?
> I can send it to anyone who wants it.
> I've updated the info on the Mcount frequency counter and that is about the
> only tricky part.
> I don't have a 209 or a 249 handy to modify, so I haven't emailed chuck
> about the Mcount.
>
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Butch Bussen" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, May 14, 2013 8:54 PM
> Subject: Re: Audible SWR meters, Analyzers, and DXCC antenna
>
>
>> Which april qst article? My friend built it, and the one chi which is a
>> regulator or something, he says is very very critical. I can't remember
>> the number, and it may not be a regulator, but all I can tell you is it
>> doesn't work. The guy knows what he is doing, worked as an engineer for
>> the government for years doing neucliar testing and all that. I guess
>> he has given up on it, so at this point I don't even have one that isn't
>> modified.
>> 73
>> Butch
>> WA0VJR
>> Node 3148
>> Wallace, ks.
>>
>>
>> On Tue, 14 May 2013, Gary Lee wrote:
>>
>>> the mod for the 209 analyzer uses off the shelf parts. A 556 dual =
>>> timer, and I have forgotten the other dual op amp chip. Nearly the same
>>> =
>>> circuit as in the april qst article.
>>>
>>> Gathering parts to attempt the build after dayton. If I can make it =
>>> work, I plan to try the mfj swr meter mod bill mentions.
>>> I will try if successful to get our club bo take it up as a project.
>>> More as I go along.
>>>
>>> Gary Lee
>>> [log in to unmask]
>>>
>>>
>>>
>>> On May 11, 2013, at 11:30 PM, Butch Bussen <[log in to unmask]> =
>>> wrote:
>>>
>>>> I boughtone of those and had a friend who said he'd modify it for me =
>>> as=20
>>>> per the article in qst 4 or 5 years ago. It appears to use a very=20
>>>> special chip and he still hasn't built it, guess I'll scratch that=20
>>>> one...
>>>> 73
>>>> Butch
>>>> WA0VJR
>>>> Node 3148
>>>> Wallace, ks.
>>>> =20
>>>> =20
>>>> On Sat, 11 May 2013, John Miller wrote:
>>>> =20
>>>>> 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
>>>>> =20
>>>>> =20
>>>>>> 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.
>>>>>> =20
>>>>>> 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.
>>>>>> =20
>>>>>> 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
>>>>>> =20
>>>>>> 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.
>>>>>> =20
>>>>>> 73
>>>>>> Colin, V A6BKX
>>>>> =20
>>>>> =20
>>>
>>>
>
>
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