Best Low Band Antenna

[LowBandRadioDog]

I've been searching the web for the best type of low band antenna with maximum gain & ground hugging effect which leaves out any quarter wave type & it appears that the 5/8th wave is best for that, with that in mind which is the most effective, the vertical dipole, omni or ground plane? I'm not concerned about bandwidth just gain. I've checked out the stacked folded dipoles & they are just way to long to be practical for me, also kkn50 since you have the greatest success at capturing low band signals what brand & model dipole & coax do you use?

 

[SCPD]

Questions

Are we talking about a mobile or a base?
Are we talking about 30-50 Mhz monitoring, or something lower, like the HF ham bands?
Are you wanting to work DX, or just work or listen distant ground stations?

 

[LowBandRadioDog]

Thanks for your speedy reply Wyandotte, it would have to be a 30-50 MHz base antenna & I am really interested in monitoring local communications but skip & tropo is more then welcome too but that's why I want to maximize the antennas ground hugging effect while still getting as much gain as possible.

 

[ko6jw_2]

Finding good low band monitoring antennas is difficult. Austin makes a multi-band antenna (Ferret) that includes low band, but it is expensive and has received mixed reviews. Commercial vertical dipoles are available from Tele-Wave, but are extremely expensive. Also hard to mount because they must be mounted a quarter wave length from the supporting structure.

I have considered building a j-pole for low band. I have seen 6 meter j-pole designs where the mast is part of the antenna. I think this is practical and inexpensive. The j-pole is a vertical half wave.

Here in California we have one of the largest low band systems still around (California Highway Patrol). Monitoring is a challenge because they mostly don't use repeaters.

If you want to work skip, it is important to consider the angle from which the waves will arrive. Having an antenna that hugs the ground may be counter productive. The other issue is that ship is either working or its not. When its working you'll pick it up with a simple antenna. When its not, it doesn't matter what kind of antenna you have.

The 30-50 Mhz band exhibits different characteristics depending on the part of the band you're listening to. At the low end of the band you have similar characteristics to the 10 meter band. At the upper end you have a situation more like 6 meters. Skip will generally diminish as you move up the band.

I was once on the bridge of a Seattle city fire boat and commented to the captain that his old 33Mhz radio was on the same frequency as Los Angeles city fire. He said he knew that and talked to them once in a while when the skip was working. (No PL in those days).

If I build a low band j-pole, I'll post results on RR.

 

[teufler]

If mobile, the Austin Sprectra is what I have used. The top section, you actually cut for the frequency desired. I had mine cut for 42.12. Worked very good, as long as my state had low band. Now low band around here is becoming a distant memory. Like other Austin products, there are pricey.

 

[ko6jw_2]

Yes, I use the Spectra and it works well for CHP. I have not tried the Ferret due to the price and the mixed reviews I've seen. Antenna Specialists made some good low band monitoring antennas, but they are long gone. Discones tune very sharply. I have one that I cut for 42Mhz and it is adequate, but not great.

 

[byndhlptom]

Low band antenna

Old CB base antennas can work well.

Cushcraft has a low band Ringo that should be an option. They also made both 10M & 11M ringos, a used one could be cut down easy enough.

Getting gain will be the hard part, most 6M antennas are 1/4w (dipole/groundplane, etc). with a 1/4w aroung 4ft, gain = big antenna

as previously mentioned, 6M can be interesting..... there's a reason it's refered to as the "magic band"

 

[N8IAA]

The best low band antenna I ever had, was a 108" metal CB whip married to a radio shack ground plane antenna, mounted on the metal stink pipe on the house back in Ohio. Not only was it great on CB, but could hear lo-band skip.
Used to have a 10m Ringo that was great on those frequencies, also had been attached to the metal pipe. Couldn't have asked for a better ground for either of those antennas.
Larry

 

[prcguy]

If your listening to one specific frequency a tuned antenna will benefit, otherwise a ground plane, dipole, etc can be 10 or 20dB down when you get away from resonance. Also consider skip signals in the VHF low band will arrive at low angles so a good antenna for local/line of sight reception will also be best for skip.

I haven't done much VHF lo listening lately but have a big inventory of broad band military antennas that cover roughly 30 to 76MHz or 30 to 90MHz range and have used them extensively in the past. Some are huge Discones, some are big bicones and the best is the COM201B, currently fielded by the US Army, Marines and others.

The COM201B covers 30 to 90MHz in a surprisingly small package and outperforms the 18ft tall OE-254 bicone it replaced. Here is some info on the COM201B: Broadband Tactical Communications Antennas

COM201Bs are a bit expensive surplus but you can find the center cone and balun from a OE-254 fairly cheap and make your own elements for a very good 30 to 88MHz bicone antenna. Here is one on Ebay now for $42 but they show up for much less.
prcguy

 

[LowBandRadioDog]

Thanks gent's for your very informative replies, before I posted my query I rigged up a quick DIY dipole antenna comprised of two 11' sections of 12 gauge wire soldered to each terminal of a 75-300 ohm TV antenna transformer, I cut a 6' piece of 75 ohm coax with an F connector on one end & a solderless BNC connector on the other end & hung it from the top of one of the windows in my home office & just draped the rest of the antenna along the floor behind my desk, this was an act of total desperation since I really needed to know if I could even receive local signals much less skip or tropo before investing in anything worthwhile, be it scanner or antenna, well last night while websurfing, the scanner started with WWV at 25 MHz, before things quieted own around 1AM I received 33.7 MHz, 30.64 MHz & 30.82 MHz respectively, actually as I type this I am listening to WWV on 25 MHz but the signal is seriously fading in & out, none of these frequencies were local according to the www.fcc.gov search index so I would say they were skip, the source of these signals I have absolutely no idea however I will work that out in time since kkn50 gave another member some very good tips in another thread, I am working with a BC9000XLT & a BCT-8 but plan on getting a 15X & an Airspy & hooking them up to this 6 Meter Repeater Antenna 1/2 Wave Coaxial Vertical Antenna Design using Andrew 1/2" heliax through an Apex SPL-2 splitter. I've seen some commercial grade antennas but I think $300.00 to $2,700 for an antenna to connect to a $150.00 scanner is just too extreme for me, well at least for now.

BTW: I miscalculated the lengths of my DIY dipole, the total length was supposed to be 11' not each leg so it probably was really tuned to 20 MHz not 40 MHz like the directions stated, but lo & behold it did work, again gents, thanks for your time & very good advice, I'll keep in touch as things progress & enjoy your weekend.

 

[kkn50]

If cost and size are not concerns, I would go with a 30 - 88 MHz Log Periodic.

I've been searching the web for the best type of low band antenna

 

[kkn50]

I'm just using a homemade 10 meter dipole.

kkn50 since you have the greatest success at capturing low band signals what brand & model dipole & coax do you use?

 

[mancow]

Mine is just 32 MHz dipole made from some copper wire tied to a Winchester 30.30 plastic shell holder thing and fed with RG59. It works fine.

 

[prcguy]

What about that military low band log I sent you?
prcguy

Mine is just 32 MHz dipole made from some copper wire tied to a Winchester 30.30 plastic shell holder thing and fed with RG59. It works fine.

 

[ab3a]

More than the actual antenna type, I recommend altitude and the lowest loss transmission line you can afford. I suggest using RG-213 for runs longer than 50 feet.

If you're looking for skip, then a horizontally polarized log periodic should do quite well. If you're looking for local traffic, a discone will do well. But most of all, height above terrain matters most. Altitude is what brings in more signals than gain. Antenna gain is what you use once you're up there.

 

[prcguy]

Antennas, both horizontal and vertical will have lower angle of takeoff when the feedpoint or highest current point is at half wavelengths above ground and the more 1/2 wavelengths the better. This is best for both local and distant skip.

Its hard to do when covering a broad range of frequencies because the sweet spot will need to change.
prcguy

More than the actual antenna type, I recommend altitude and the lowest loss transmission line you can afford. I suggest using RG-213 for runs longer than 50 feet.

If you're looking for skip, then a horizontally polarized log periodic should do quite well. If you're looking for local traffic, a discone will do well. But most of all, height above terrain matters most. Altitude is what brings in more signals than gain. Antenna gain is what you use once you're up there.

 

[mikepdx]

More than the actual antenna type, I recommend altitude and the lowest loss transmission line you can afford.
I suggest using RG-213 for runs longer than 50 feet.

Height - definitely
But, it's antenna, antenna, antenna.
The more metal in the air (capture area), the better.

Coax cable losses are still mighty small at 30-50 MHz.
No worries there - only 1.4 dB/100' @ 50 MHz using even RG-6 CATV cable

 

[mancow]

What about that military low band log I sent you?
prcguy

I'm trying to figure out where to mount it. If I put it on the roof above the living room area the tv and uverse thrash the band.

I don't have a tower. I have two large trees but they have lower branches that get in the way. I might be able to somehow hang it from one though.

I might try the other side of the house above the shack. It's the tallest part but then there is the networking and pc stuff below bit it might not be too bad.

A friend is planning on putting up a tower at a lake house. I might be able to set it up there and use proscan.

 

[prcguy]

Don't make me come over there and install that thing for you.....
Get it up! Can't you just get it up?

Ooh, that didn't sound right. Oh what you people must think of me now........
prcguy

I'm trying to figure out where to mount it. If I put it on the roof above the living room area the tv and uverse thrash the band.

 

[LowBandRadioDog]

Best Low Band Radio Antenna

Antennas, both horizontal and vertical will have lower angle of takeoff when the feedpoint or highest current point is at half wavelengths above ground and the more 1/2 wavelengths the better. This is best for both local and distant skip.

Its hard to do when covering a broad range of frequencies because the sweet spot will need to change.
prcguy

Hello again gent's, I've received a bunch of tropo/skip frequencies & WWV at 25 MHz is almost constant, I've received very little local stuff, mostly DOT & 6 meter nets, CB comes & goes too, has the band been open lately or is this stuff just some kind of anomaly since you guys say you can sit by a scanner for weeks & get not one peep? I'm pretty much hearing a few things about every other day or two especially in the afternoons, I've already ordered the BCT15X & Andrew 1/2" superflex heliax coax, the dipole is going to be constructed from the plans here. 6 Meter Repeater Antenna 1/2 Wave Coaxial Vertical Antenna Design

prcguy, since I live on the 5th floor & the antenna will be exactly at the roofline equals 50' above ground level so how many 1/2 wavelengths would that be?