[HCARC] When People Ask A Question - Be Careful With The Answer

[Bob Richie]

Kerry, you make some good points and some I've had different experience with. I've bought a couple of HF rigs on e-Bay (probably before I knew better) and both have been great. Both are presently on loan to other hams. I've also bought a couple of tuners on e-Bay that have served me well and if you're looking for an older model you have to look in the used market.

As for the G5RV and Carolina Windom, both are specific antennas. A dipole fed with a 450 ohm window may or may not be a G5RV and folks need to recognize this. Likewise, not every off center fed dipole is a Carolina Windom. Since none of us has made or worked every possible combination the answer "try it and see", is not necessarily a put off. Your assessment that wire is cheap (and reusable) is an open invitation to experiment. New hams should keep in mind that in the ham radio game, propagation conditions trumps hardware every time and any antenna is better than no antenna. Operator skill is another variable and you can't gain the skill unless you operate
 
Bob
K5YB
Kerrville, TX 78028


________________________________
 From: Kerry Sandstrom <kerryk5ks at hughes.net>
To: Gary and Arlene Johnson <qltfnish at omniglobal.net> 
Cc: HCARC Reflector <HCARC at mailman.qth.net> 
Sent: Saturday, August 4, 2012 11:14 AM
Subject: Re: [HCARC] When People Ask A Question - Be Careful With The Answer
 
Gary,

I was happy to meet you at the meeting.  I didn't know who you were when we 
started exchanging e-mails.

As far as the question/answer.  When you ask a 'simple' question, it may not 
be as simple as you think.  The basic question I think was "would the AS2259 
make a good antenna for field day?"   Unfortunately the short answer is yes, 
no, sometimes and maybe.  I didn't think the short answer would be 
particularly useful.  The AS2259 antenna is a fine antenna.  It has a couple 
limitations; 1- It is designed to use NVIS propagation, 2- It operates with 
a very high SWR, 3- The center support/ transmission line is designed to 
plug into a specific military HF transceiver.

What this means is that it is really most useful for daytime propagation on 
80 and 40 meters out to about 200 or so miles.  While it will work on the 
higher bands, since most of the radiated power goes straight up, the results 
will not be very good.  The fact that it was designed to mate with a 
specific military transceiver, means it will not be easy to connect it to a 
typical modern ham transceiver with 50 Ohm coaxial output.  The fact that it 
operates with a high SWR, probably higher than 10:1, means that even if you 
could connect it to a ham transceiver, the transceiver will not be able to 
deliver very much if any power to the antenna becasue of the high SWR.  Even 
expensive transceivers with built in auto tuners will not work since they 
typically can only handle an SWR of 3:1.

The specific transceiver used with the AS2259 is an AN/PRC47.  This a 
Collins designed/built transceiver from ~1970.  It is mostly solid state but 
uses a PL177WA tube for its final amplifier.  This tube is capable of 
250-300 W on SSB but is run at ~100W, pretty conservative.  The unit uses a 
Pi-L output tuning network which is probably capable of matching antenna 
impedances from 10 to several hundred Ohms.  This is a huge range compared 
to the typical modern ham transceiver.  It is more range than modern 
transceivers with built-in antenna tuners.  The operator 's manual for the 
PRC47 talks about a plate on the transceiver that provides tuning setting 
for the antennas designed to use with the PRC47.  It also has a 'special' 
procedure for tuning to match a 50 Ohm load.  This pretty clearly 
demonstratres that the PRC47 was designed to use antennas with high SWR. 
Ultimately, this is what finally convinced me that the AS2259 antenna is a 
high impedance antenna over most of its frequency range.

Unless you have some understanding of where the answer comes from and can 
refine the question to a particular set of conditions, all the answers - 
yes, no, sometimes and maybe  - are correct.  Unfortunately, most questions 
and answers in ham radio are like that.  Ham radio is a lifelong learning 
experience.  You ask a question, if the answer doesn't make sense, you ask 
another question.  You read.  You listen to other peoples discussions.  You 
ask another question.  And so it goes.

I personally believe the AS2259 is a good antenna for field day.  It will 
take some effort to physically connect it to a ham transceiver.  You will 
have to use a wide range antenna tuner.  It is primarily useful for NVIS 
propagation on 80 and 40 meters.

One of your early statements is something that greatly concerns me.  Too 
many people spend to much money on  a fancy transceiver and 'special' 
antenna that they can never figure out how to work.  Most of us old timers 
started on the cheap with second hand (or worse) transmitters and receivers 
and a twin lead dipole.  No, they didn't work well at all, but we were all 
stuck on the novice bands and most of us were in the same boat.  Misery 
loves company!  Most of the guys I worked were less than 100 miles away.  I 
was in Mass. at the time.  To work Maryland or Ohio or even Pennsylvania was 
a big deal.  QST had at least one article a month that was practical 
information for new hams to use to help them improve their station.  Most of 
the articles didn't require spending large amounts of money.  It was only 
after a couple years of learning and practicing, that most hams actually 
went out and spent any real money on a fancy radio.  Unfortunately life is 
different now.  There are no novice bands.  Its not easy to find decent used 
equipment.  QST seems to have sold their soul to the manufacturers of fancy 
equipment.  CQ, Ham Radio and 73 (old ham magazines) have all dissappeared. 
The problems are still the same.  How do you find a group of new hams with 
the same ability level that you have so you can learn together?  How do you 
find some reasonably priced and performing equipment that you can learn on 
until you think you are ready to make that big purchase?  How do you know 
what you should expect from your station?

These are not easy questions and I don't know the answers.  Gale is trying 
to get a weekly HF net going.  Perhaps that is part of it.  It will give 
people a chance to try different antennas and settings on their equipment to 
see what makes an improvement.  Things like the Tech Corner are part of the 
answer too, but you have to get control of it on your own!  If the level is 
too deep, ask questions to move the discussion to your level.  When I talk, 
I love questions, it shows someone is interested.  Read all you can.  Old 
ham magazines (1960's 1970's) are great.  They are technically readable and 
cover real problems unlike most of what you see today.  Read old ARRL 
Handbooks, antenna books, VHF handbooks etc.  There are a lot of them out 
there. They don't change quickly, read ones about 10 years apart and you 
will get most of it.  Take what the manufacturers say with a lot of salt. 
They are just trying to sell you on something they have.  Try to find used 
equipment locally, ie, Austin and San Antonio.  Avoid e-bay, QRZ.com 
swapmeet, etc.  A lot of the ads I see, the seller is just plain clueless or 
worse.

The G5RV and Carolina Windom antennas are another problem.  You will find a 
lot of people who are convinced these antennas are nothing short of 
miraculous.  Too spend nearly $200 for a 135 feet of wire and a couple short 
lengths of transmission line is, in my opinion, criminal.  These antennas 
will not work any better than a plain old dipole.  The problem with any 
antenna is matching to the transmitter.  I believe you are much better off 
spending your money on a good antenna tuner.  My main point in the comments 
on the Carolina Windom and the G5RV is to show they are both derived from 
the Windom antenna, pre WW2, and the premise the Windom is based upon, no 
longer applies.

I hope this summary does you some good.  Again, there is no simple answer to 
your question.  Remember, my comments are my opinion, especially on the G5RV 
and Carolina Windom.  There are many who would disagree with me , some 
violently.

Kerry 


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