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Antennas: A Different Twist on a Dual-Band VHF/UHF J-Pole
CQ magazine ^ | March 26th, 2021 | ROBERT GLORIOSO

Posted on 05/10/2021 6:55:46 PM PDT by tbw2

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To: mylife; Lazamataz
you can has license

There are so many idiots out on the HF bands these days that don't have licenses it's sickening.

All I can say is this Laz: if you want to do it RIGHT, study and get your license.

If you don't care, then don't get your license and see how many people will talk to you on the amateur radio bands that ARE licensed. It won't be many. Those that aren't licensed won't care and will be happy to talk to you on 80m.

21 posted on 05/10/2021 8:06:15 PM PDT by usconservative (When The Ballot Box No Longer Counts, The Ammunition Box Does. (What's In Your Ammo Box?))
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To: tbw2

Stop arguing with customers who know more then you evidently do.


22 posted on 05/10/2021 8:15:48 PM PDT by bigbob
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To: tbw2

With a parabolic dish antenna, you can have separate feed horns and be able to receive that range.

Software defined radio? I’ve never owned one. The issue I see with them is selectivity.

Computers and sensitive receivers are not friends. I learned this back in the early 1980’s. My analog RF receivers near poorly shielded Z80 computers were snowed with white noise. Even the best receivers had issues.

Later I bought a Robot 800 CW and TTY (computer) keyboard. It was the first such machine that generated low white noise.

This brings back some great memories.


23 posted on 05/10/2021 8:21:30 PM PDT by Texas Fossil ((Texas is not where you were born, but a Free State of Heart, Mind & Attitude!))
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To: Vermont Lt

Thanks


24 posted on 05/10/2021 8:24:10 PM PDT by ptsal (Vote R.E.D. >>>Remove Every Democrat ***)
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To: tbw2

The best antenna for general use with an SDR, like the little 20$ dongles, is a discone. The discone has little gain but it has an enormously wide bandwidth.

If you place the discone up high and use low-loss feedline the results are very good.

Parallel line, like ladder-line or twinlead, with matching transformers is good if the discone is quite a distance from the SDR. This type of feedline has very little loss even at microwave frequencies.

Another good option is LMR400 coax, but it is a little pricey.

This online SDR uses a cheap dongle to receive medium wave through 10 meters... this sort of setup can be constructed at home for relatively little $.

http://na5b.com:8901/


25 posted on 05/10/2021 8:26:54 PM PDT by Bobalu (When I die I want to be buried in Chicago so I can stay active in politics)
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To: Bobalu

I lived out West in Silver City, NM. Lived in NM from 1972-1986.

Was in the wholesale hardware distribution business. Traveled from Alamogordo to Sierra Vista AZ. and as far North as Truth or Consequences.

I absolutely loved the Amateur Radio Community there. Best engineers and techs I have ever known.

Those were good memories.


26 posted on 05/10/2021 8:28:33 PM PDT by Texas Fossil ((Texas is not where you were born, but a Free State of Heart, Mind & Attitude!))
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To: Vermont Lt

lol...


27 posted on 05/10/2021 8:29:25 PM PDT by dragnet2 (Diversion and evasion are tools of deceit)
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To: mylife

Turn all knobs max right to be heard. And in certain conditions, shouting into the microphone helps.


28 posted on 05/10/2021 8:37:19 PM PDT by dragnet2 (Diversion and evasion are tools of deceit)
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To: tbw2

bookmark


29 posted on 05/10/2021 8:51:25 PM PDT by dadfly
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To: Blue Highway
but I listen to am radio and the reception is worse now than it ever was.

Does your AM radio have a connector for hooking up an external antenna?

Years ago I tried one of the highend C.Crane antennas, and was underwhelmed.

What is the frequency of your preferred stations? AM radio is prone to static and interference. Some radio stations have an FM based repeater that can be picked up with a digital radio.
30 posted on 05/10/2021 9:20:27 PM PDT by Dr. Sivana (Dr. Sivana is not a medical doctor. He is a comic book doctor of the Mad Scientist variety.)
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To: dragnet2

I had to laugh. That was me at first, thinking that shouting into the mic would help. I still have to watch that when working a dx. Now I want the best sounding signal and learned to dial back the mic gain and compression


31 posted on 05/11/2021 4:39:09 AM PDT by dis.kevin (Dry white toast)
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To: mylife
a good analog front end is everything

That’s what she said...

32 posted on 05/11/2021 5:35:25 AM PDT by IncPen ("Inside of every progressive is a Totalitarian screaming to get out" ~ David Horowitz)
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To: Dr. Sivana

970 WFLA from Tampa but I’m in Sarasota. Works clear mostly but more static that it used to have driving in the same area from 10 years ago. Also I have a newer car than I did then as well and the reception is worse. No idea about an additional hook up. I can listen to IHEARTRADIO and stream the radio station via my car’s bluetooth, but then I run up my data use which I’d prefer not to do.


33 posted on 05/11/2021 8:47:36 AM PDT by Blue Highway
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To: Blue Highway
Also I have a newer car than I did then as well and the reception is worse.

AM radio is deprecated in newer cars. WFLA-AM 970 is 25,000 day/11,000 watts after sunset, is is okay, but not like the big 50,000 watt stations (KDKA [Pittsburgh], WTIC [Hartford, CT], WLS, WBBM [Chicago], WFAN, WCBS, WOR, WABC [NYC]) 970 is a good spot on the dial,. lower means more interference, higher means less distance.

WFLA has an FM translator in Gulfport @ 94.5 FM. It is low power (250 watts), but it is closer (and mostly over water, a good thing).

Many new cars also do not have an external antenna, but rely on a wire embedded in the windshield (front or rear). That is never going to be as good as an external whip antenna, but it cuts down on vandalism and car wash damage.

If you look at this site (https://radio-locator.com/cgi-bin/pat?call=WFLA&service=AM&h=N) you will see that Sarasota is right on the edge of daytime reception.
34 posted on 05/11/2021 12:04:21 PM PDT by Dr. Sivana (Dr. Sivana is not a medical doctor. He is a comic book doctor of the Mad Scientist variety.)
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To: dis.kevin


35 posted on 05/11/2021 12:14:28 PM PDT by dragnet2 (Diversion and evasion are tools of deceit)
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To: Texas Fossil

re: “J-poles are often dual band. If you are looking for a simple dual band antenna it works pretty well for line of sight radio”

SO DOES a wire sticking out the back of the RADIO.

You nutjobs just won’t let it go, will you?

You’re either green and new to radio, or so old you forgot ALL you learned.

EITHER WAY, J-poles still SUCK.

People like spread myth and disinfo without the slightest understanding what the hell you’re doing to NEWBIES.


36 posted on 05/11/2021 7:53:17 PM PDT by _Jim (Save babies)
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To: Texas Fossil; mylife

Yes it can happen. In august a couple of years ago, I was listening to WRR from dallas on 101.1fm. It was very clear and very surprising, because I was in Pinedale, Wyoming at the time. About a thousand miles.


37 posted on 05/11/2021 8:26:42 PM PDT by Professional Engineer (Looks like I'll have to buy the White Album again.)
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To: Professional Engineer

That must have been on one of the few remaining VHF TV channels. Not much of that spectrum left.


38 posted on 05/12/2021 9:11:19 AM PDT by Texas Fossil ((Texas is not where you were born, but a Free State of Heart, Mind & Attitude!))
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To: _Jim

“You’re either green and new to radio, or so old you forgot ALL you learned.”


I’m 73. Hold an Amateur Extra and a GROL Commercial Radio License.

Have taught electronics at an Airforce base.

We are through. Your insults are not appropriate here.


39 posted on 05/12/2021 9:19:55 AM PDT by Texas Fossil ((Texas is not where you were born, but a Free State of Heart, Mind & Attitude!))
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To: Bobalu

Agree. Totally correct.

I admire simple solutions. It is the part of design today that is missing.

Yes, RF is still somewhat black magic. But it has been in use a long time.

UHF and upward, you are no longer an electrician you are a plumber.


40 posted on 05/12/2021 9:31:03 AM PDT by Texas Fossil ((Texas is not where you were born, but a Free State of Heart, Mind & Attitude!))
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