Friday, October 14, 2016

RADIO ANTENNA'S

Hello and welcome back... Antenna's or Aerials (American?) are the lifeblood of our radios. Without them they would not work properly.

So many Antenna's are on the market these days, its hard to decide which one is right for you.

While i'm not an expert, i have been using radios since i was 16 (now 46) and have used a fair few antenna's, some good, some not so good, and some are just crap.


*****SHORTWAVE*****

 Shortwave is low band starting about 0.5Mhz to 30Mhz.

The Longwire antenna is a popular choice.

Its basically, attach a rope or string to a tree, end with an egg insulator and attach a very long piece of copper wire to the other end, the longer the better and up high, the higher the better. Tie the end to an egg insulator and attach to a tree. (see below)

Other HF/Shortwave antennas to use would be Whips similar to what the Army use.

For indoor use, the old twin antenna wire (or ribbon wire) worked well, just make sure your radio is away from TV, Microwave ovens, florescent lights, etc,etc.
Tac the ribbon cable across one end of the room, across the roof line is best and all the way around if you can, then solder the ends together and attach coax to the solder and coax to radio.

   
I am currently using a Mobile One SCATX antenna on a rooftop pole. The antenna is rated to 30Mhz but for Shortwave, It just booms in..I'm very impressed.
Been able to get stations in the U.S, Japan, China and even Russia using the Icom IC-R1000 radio.
 

*****SCANNER*****

The worlds your oyster, or so the saying goes.

The Discone Antenna is the most popular.
With unity gain, its a trusty performer but at times not cheap.
Also there's the problem that if your discone is on a mast outside, everyone knows you own a scanner. (pic below)

Whip antenna's are also a good choice, ether stainless steel or fiberglass.

The Mobile One SCATX antenna is my current choice, it has gain on UHF (4.5db), Airband (2.1db) and VHF Low (Unity). Like i stated in the Shortwave post, it picks up pretty good as well.

TV Antenna's can also be used in fringe areas.

The 50 - 75ohm difference will not cause a problem. (Scanners are 50ohm while TV is 75ohm). TV Antenna's are rated to 30Mhz to 800Mhz, good enough for scanner use.

Keep in mind that TV Antenna's are very directional.

The only thing to be careful of, is if the TV antenna has a pre-amp attached, it can cause signal overload that can damage your scanner.

I was living in an area (Faulconbridge) and it was down in the sticks. I went to the top of the property, mounted a scanner antenna in a tree, ran super thick coax down to the house to minimize loss but it was still a crap signal.
In desperation i plugged my scanner into the TV Antenna socket and 'Boom', everything came in clear, problem solved.

Other Scanner base antennas I have tried is the Mobile One SCBASE antenna.

I was not impressed. Thankfully, i did not pay for this 'bit of tube and wire'.

Asking price at the time was $160 and was sold at Dick Smiths.

The SCBASE antenna is a white plumbers tube attached to a smaller aluminum tube for mast mounting. Inside this antenna was coax to the center where very thin wire was wound up and down inside a smaller tube.

I wonder if the makers actually tested this antenna before putting it on the market.

My mind was taken back to when i spoke to Peter Pride (Owner of Mobile One) and he stated that they had to import these antennas because Dick Smith wanted them to. (don't quote me on that, its going by memory and was about 10 years ago but its similar to what i remember)

He told me to save my money and buy the antenna i have now, an antenna he designed and made..The SCATX.
An antenna that has outperformed my expectations.

Handheld antennas for scanners can have a BNC or SMA connectors.

Diamond Antennas make some good antennas.

I was using a amateur band antenna where 144Mhz and 400Mhz had between 2.4 to 4.5db gain.
Sadly this antenna bent really easy and lasted about 6 months.

Mobile one has BNCSCAN or SMASCAN antenna.
This is my current antenna i use on my scanner, its longer than the stock antenna and performs pretty well. Sells for $40/45

The best antennas for handhelds, i have found, are the ones similar to the previous Diamond antenna.

Amateur band antennas that have gain for 144Mhz (also good for Airband) and gain in UHF band.

In fact, i think the handheld market is the hardest of all, some antennas of the Chinese variety claim to have gain but the proof is in the pudding.
Most times they struggle to give good reception and are cheaply made.
  

*****UHF*****

Brand 'RFI' have some of the best UHF antennas around.
I am currently using the stainless steel whip with a elevated feed for GRN reception.
Even in strong wind, it performs very well and has around 6.5db gain. (see below)


Benelec Antennas are other i would recommend.
One Benelec base antenna which is a 477Mhz  is rated at 9db gain, that's pretty good. See Here, as does Mobile One (COL9) see here
Other brands include GME, ZCG, Uniden, Minespec and Aerpro.

Beam antennas are very effective for home UHF setups, they're directional, offer decent gain and are durable to weather conditions.

Handheld antennas often include the 'stubbie' quarter wave (seen on most 2-ways),most are unity gain with longer antennas offering db gain.

Antennas are available from Icom, Mobile One, GME, Vertex, Motorola and various 'Chinese' brands.
A small selection here


*****AIRBAND*****

Base antennas for Airband are hard to get, not many suppliers sell Airband antennas.  (that i know of)

Mobile One sell both Base and whip variety see here

I sort of made my my own Airband Antenna
Ive currently got a elevated feed from 27Mhz (2.1db gain) and a long VHF stainless steel whip (made for 76Mhz?).
Picks up really well, so good in fact, it beats my Mobile One antenna on the roof which has 2db gain.

From Springwood, I can recieve Sydney ATIS (5bar/full), Richmond (4bar), Camden (2-3bar) and Bankstown (1bar) (bar = signal strength)
With the Mobile One roof antenna, I only get about half of what I receive on the above whip setup. (Airband only).

Another good base Airband antenna is the Diamond D-103, Its has 2.15dBi (120MHz), 5.5dBi (300MHz) See Here

Handheld antennas are sold by Mobile One as well.

You can also get replacement Airband antennas from Icom and other makers of Airband radios, just be sure check that the connection is the right one for your radio, eg BNC or SMA


*****AMATEUR RADIO*****

The most popular base Ham/Amateur radio antennas would have to be the huge beam antennas.

Depending on which band your interested in, some require a high mast, guy wires and council permission before you can start transmitting (license required) check em out here

Also Dipole or Wire Antenna's are popular with Ham radio.

Makers of Antenna's to check out for Ham/Amateur radio include Cushcraft, Diamond, Hy-Gain, T.G.M, & Ultrabeam, 

Amateur Radio handheld antennas are also excellent for scanners because most have gain in the 144 / 400Mhz range.

Once again Mobile One (see here) sell a good range of Ham Antenna's as does Chinese brands that have flooded the market.
Brands like Baofeng, Wouxen,Quansheng, Puxing have replacement antennas available. Some good, some not so good.

One of the best I have found is a brand called Sainsonic, cute little antenna, kinda looks like a toy but picks up really well. (better than the stock antenna) and has 2.1 db gain. (see below)


Please add anything i may have missed in the comments below.
I started writing this 4 hours ago and my brain is now mush. hahaha

Do you have a favorite Antenna you wish to share with readers? Comment below.

Also if you have a company that sells radio antenna's, feel free to advertise below in the comments section. (no spamming)     
  
Don't forget to shout me a coffee (see link top right corner).. Any amount big or small is much appreciated and it keeps this site happening :)

LINKS

http://mobileone.com.au/1a_index.html

http://www.prestigecom.net.au/

http://actioncommunications.net.au/

http://www.andrewscom.com.au/Antennas

http://www.strictlyham.com.au/

https://baofengtech.com/


#Antenna
#Shortwave
#scanner
#UHF
#VHF
#Amateur
#Airband

#Disclaimer - This post is not an advertisement for Mobile One antennas or any other company. Its the products that i have used and they work well (and i'm very picky.)
If i find products that work well, i'm more than happy to tell the world, if its rubbish.. well, i will try to let you down gently in a hope you will fix the problem.
Thanks.



No comments:

Post a Comment

Note: Only a member of this blog may post a comment.