HFU HF Underground

Loggings => VHF/UHF Logs, including satellites and radiosondes => Topic started by: Elf36 on October 26, 2021, 1903 UTC

Title: VHF/UHF general listening antenna
Post by: Elf36 on October 26, 2021, 1903 UTC
I may have brought this up in the past. Just wanted to get some general opinions on antennas for VHF/UHF listening. Aircraft, Marine, FRS/GMRS, Taco Bells drive thrus etc. I know that discone's are known for being an all around RX antennas for various bands above 30 MHZ. Are they really any better than,say a 2m/440 vertical? I owned a tram 1411 (The bigger discone) , but didn't keep it long enough to form an opinion. A guy I know really like it, so I gave him a deal on it. The antenna was quite large and after putting a bit dab of glue on the jam nuts and rubber end caps, it seemed to be a pretty solid piece. I attempted to use for TX/RX on 2M/440 with fairly disappointing results. It also claimed to work for 10/11 meters, but I did not even attempt. On that note. If discone's are recommended, is it worth the extra cost for a Diamond as far as actual RX gain? Would be nice to have a dedicated VHF/UHF antenna on the other RSP2 ant port I'm not using.
Title: Re: VHF/UHF general listening antenna
Post by: Josh on October 28, 2021, 0016 UTC
No gain on a discone compared to a 2m/70cm vertical, unless the disconey was huge.
Consider a discone to be a dummy load for rxing, incredibly broadbanded but no gain, some use a amp to help it along.

I think the main diffs between the various brands of discone revolve around construction materials and methods and wether it has a stinger or not. A stinger can help in lower band performance such as for cb or 6m use, some guys put a short dual band element in place of the cb/6m stinger to get some gain there.
Title: Re: VHF/UHF general listening antenna
Post by: Elf36 on October 28, 2021, 1107 UTC
Thanks. I've always felt that way to. I'll just throw a J-pole up with some LMR-400 for now and see how that works.
Title: Re: VHF/UHF general listening antenna
Post by: RobRich on November 02, 2021, 1416 UTC
I posted a very basic lightweight VHF receiving antenna in your NOAA/NWS thread.

A discone has no inherent gain, but like Josh said, you can use a remote preamp to help the situation.

Height is the important factor for VHF, since you are typically dealing with line-of-sight transmissions. Get whatever antenna as high as possible.

^All that said, I tend to use the lazy approach for local to regional VHF, as in just using my existing 9' ground-mounted vertical. I have a discone, crossed FM dipole, etc. collecting dust in storage.
Title: Re: VHF/UHF general listening antenna
Post by: Elf36 on November 02, 2021, 1803 UTC
I saw that. Thanks Rob.