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Messages - ultravista

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Equipment / Re: Optimal EFHW Configuration for Low Angle DX?
« on: June 15, 2023, 1520 UTC »
RobRich - a horizonal positioned EFHW will have a lower radiation angle than a sloper, L, or V?

Equipment / Optimal EFHW Configuration for Low Angle DX?
« on: June 14, 2023, 1305 UTC »
Looking for configuration recommendations for running an end-fed half wave, or non-resonant wire, for best low angle radiation. My current configuration for a MyAntenna's 80-10 is top fed @ 30 feet sloping to 20 feet.

My primary interest if HF DX on 10-40 meters.

General Radio Discussion / Re: Garage Door Opener Damaged by HF RF?
« on: December 11, 2022, 1807 UTC »
I have not replaced anything in the house for a while, no new electronics, nothing new at all.

This is very strange. I understand that some devices may act-up when transmitting, but my two door openers are practically deaf now. I bought new batteries today and the door won't open unless the remote opener is a few feet from the receiver. The wire buttons of course open/close the door perfectly.

Last night when we returned home, the garage door bulbs were off, the garage was dark, and it still wouldn't open - I waived the remote around in the air with the button pressed and it eventually opened.

On a perhaps related note, my Vizio soundbar mysteriously died Friday night while watching a movie. It is dead. I opened it and didn't see any blown/bulging capacitors. Googling the problem, I see many others have similar problems with the Vizio soundbars crapping out after a few years. It is coincidental that the garage door openers and soundbar are both affected the same day.

I was not transmitting when the soundbar died - the radio was off and we were watching a movie.

As I lead-off, very strange.

Could the front-end of the garage door receiver be damaged? I presume it either works or doesn't work. It doesn't make sense that it works but only when the opener is a few feet from the receiver.

General Radio Discussion / Re: Garage Door Opener Damaged by HF RF?
« on: December 11, 2022, 1806 UTC »
How close is the 40 meter transmit antenna to the opener receivers?

On the deck. The coax runs 20 feet to the unun. If counting the height, about 30 feet.

General Radio Discussion / Re: Garage Door Opener Damaged by HF RF?
« on: December 11, 2022, 0342 UTC »
The garage door openers are Chamberlain, both operate w/a different remote. I do have LEDs in the garage and they have been there for at least a year. Prior to a few days ago, regardless if the garage LEDs were on or off, the garage doors operated from 30+ feet. Today, the range is underneath the garage door opener (receiver).

The environment is the same - the only thing new is my transmitting @ 100w from an end-fed antenna.

It doesn't make sense that the garage door receivers would be permanently affected, but something has rendered them practically useless.

My third remote opener is only a few weeks old. The battery is new and the 'transmit' LEDs on the remote are bright. I have to put it up in the air by the garage door window to open the door. The receiver antenna is visible - straight down as it always has been. The same applies for the other opener.

General Radio Discussion / Garage Door Opener Damaged by HF RF?
« on: December 11, 2022, 0123 UTC »
Yeah, this is a crazy one.

My wife's garage door opener stopped working yesterday. I replaced the battery and it works when very close to the garage door receiver, like underneath.

Today, my son tells me his garage door opener isn't working. His is 2 weeks old and opens a different door (not the same as my wife). It works when you elevate it to the window and a few feet from the receiver.

So I tested mine, the same door as my son, and it took has a extremely limited range. I could not open the door unless I held the opener up high @ the window.

Previously, we could open the door at the top of the driveway, at least 30 feet away. Now, unless it is in line-of-sight with the receiver, the receiver doesn't receive.

The only thing different is my operating an end-fed @ 100 watts on 40 meters. Prior to my operating @ 40 meters, the garage door receiver had a decent +30 foot range. Now, it's practically deaf.

The low receive occurs when not transmitting, like tonight, when we went out to eat. This is when my son told me his door opener doesn't work.

So ... did my amateur radio operation permanently damage the garage door receivers?

Equipment / Re: Non-Resonant EF Antenna Wire Lengths
« on: December 05, 2022, 1506 UTC »
I would like to work 80-10m, and possibly 160m if I can - transmit & receive.

Equipment / Non-Resonant EF Antenna Wire Lengths
« on: December 04, 2022, 1642 UTC »
I have a Palomar Engineers 9:1 HF Unun for non-resonant wire lengths and trying to figure out what length of wire to start with for 160-10m. There are many different recommended lengths from several different manufacturers/expert and the lengths are different for each one. I do not have an analyzer at this point so measuring SWR is not an option. I can run up to 150ft easily.

For those of you with a non-resonant end-fed, what length of wire and counterpoise(s) do you find optimal for 160-10m?

Palomar Engineers 9:1 Unun
* Bands Covered 160-80-40-30-20-17-15-12-10 wire recommendations in feet = 135, 141, 173, 203

Balundesigns 9:1 Unun
* Coverage of 160m through 10m (wire recommendations in feet = 53, 59, 7,2 88.5, 98.5, 124.5, 146, 162, 175

VE3EED the "Best" Random Wire Antenna Lengths
* 29, 35.5, 41, 58, 71, 84, 107, 119, 148, 203, 347, 407, 423

Yeah, I was thinking the same thing.

Other / Re: 14.313mhz usb ? 2:18utc
« on: November 26, 2022, 1628 UTC »
I had an interesting conversation with VE7KFM today. Based on his ramblings, I googled his call sign and found this page.
11 years after the first posting .. he's still going strong @ 14.313.

Is this radio worth anything?

For Sale / Wanted / Barter / VEF-SIGMA 260 1980s USSR Shortwave Radio
« on: October 23, 2022, 0241 UTC »
I am interested in selling a VEF-SIGMA 260 Shortwave Radio w/Cassette. I have too many radios and no longer use this one. I prefer to sell it to another SWL enthusiast vs. eBay.

I do not know the value and I am open for offers.

Located in Georgia USA.

Equipment / Re: indoor loop antenna recommendations...
« on: January 04, 2022, 1456 UTC »
~SIGINT~ how does it compare to the Wellbrook? I have a Pixel 1B and thinking about getting a Wellbrook as a second antenna.

Equipment / Re: LOG Not Performing Well
« on: September 19, 2021, 1332 UTC »
I did scale the LOG to about 150 feet and irregularly shaped. Just what I had of a wire bundle, made to fit without cutting.

With a direct connect to 75 ohm coax, I am pickup a local NDB, 415 khz. It is faint, but visible in the waterfall. When connected with a 1:9 balun, the signal disappears. Moving back to my smaller loop, it too was able to pickup 415 khz, but much weaker than the larger loop.

The larger loop certainly helped, but it is strung around the backyard in an odd way, not sure I would leave this as-is since it doesn't appear to have much of an advantage over the smaller 60 foot loop.

The direct connect did make a difference.

The PA0RDT picks up WWVB @ 60 khz. The Pixel, LOG, and other antennas I've tried do not. I am receiving WWVB in North Georgia.

Equipment / Re: LOG Not Performing Well
« on: September 18, 2021, 1233 UTC »
Got it, thank you.

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