HT Antennas

Started by cockpitbob, December 02, 2012, 10:28:20 PM

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cockpitbob

To start this topic I'm re-posting some HT antenna test results from another thread.

Earlier I compared the stock 7" Yaesu duck, the Nagoya NA771 ($7-$14 on eBay) and my Ed Fong shirt-pocket roll-up J-pole.  The J-pole was 7' up in a tree branch.  Originally I wanted to see if the 15.5" Nagoya was better than the 7" Yaesu duck.  The 2 performed identically. This time I added a rat tail to the HT's antenna to see its affect. 
For a rat tail I cut a piece of 22AWG stranded, insulated wire to 19.5" and stripped 1".  I wrapped the 1" of bare wire and around the SMA connector before screwing the antenna on.  In use I made sure it hung down. 

I went outside during the Sunday pm 2M nets and compared Rx readings.  Here's the S-meter results from a somewhat distant 2M repeater:

ANTENNA     NO RAT     WITH RAT
Yaesu             S5           S8 to S9+20
Nagoya           S5           S8 to S9+20
J-pole             S8       

With the rat there was a bit more sensitivity to where I stood (S-meter moving up and down as I walked around), but wholy-cow, what a difference.  All I can say is that I'm a rat tail convert.  That magic little piece of wire is now in my HT travel bag.

gil

Are those SMA type connectors? How did you connect the rat tail? What length. 19" ?

Thanks,

Gil.

cockpitbob

#2
Yes, SMA.  19.5" of wire (before stripping).  I just stripped 1" and wrapped it around the base before screwing the antenna on.  I suppose for long term use I should do something more elegant, like  ring lug.

gil


Jim Boswell

Bob,
     Good info, The 1/4 wavelength ground radial helps, as a counter-poise on a hf station or a rat-tail on a HT. Be sure and keep your SMA or BNC connectors clean. Do not over tighten SMA connectors. The rated torque for SMA connectors is 10oz/in. Guess I am old fashion, I still prefer the BNC connector. It easier to add the rat-tail to a BNC connector.
     Take Care, 73'S  KA5SIW

gil

Guess I'll have to stop grabbing my HT by the antenna  ::)

Gil.

Quietus

Quote from: cockpitbob on December 02, 2012, 10:45:36 PM
I suppose for long term use I should do something more elegant, like  ring lug.

Elegance plus good effect is a killer combination.  Thanks for your rattail info, I will be trying it.

gil

I added a 19' rat tail to my Yaesu FT-270R.
One word: WAOH!
BIG improvement..
Half bars to full bars S9+.

Gil.

geoffrain


Hi guys,

Interesting experiment. When executing this test, were you holding the HT or was it sitting isolated from your body?

Geoff


gil

QuoteInteresting experiment. When executing this test, were you holding the HT or was it sitting isolated from your body?

Holding it, the rat tail dangling over the back of my hand..

Gil.

cockpitbob

Quote from: gil on January 27, 2013, 10:41:23 AM
QuoteInteresting experiment. When executing this test, were you holding the HT or was it sitting isolated from your body?

Holding it, the rat tail dangling over the back of my hand..

Gil.
Ditto.  Real world/use situation.
My HT carry bag will never be without a rat tail.  Once I find a local 70cm net I'm going to first try it with tail cut for 70cm, then try it with a 2M and 70cm connected at the same time.  It works for fan dipoles so it probably would work with rat tails.  Then I wouldn't have to think about changing tails if I change bands.

gil

Mine stays on now at all times.. Makes a huge difference.

Gil.

White Tiger

I'm thinking about it during a boring portion of a sales meeting...

Where is my thinking wrong considering the rat tail set-up as a 2m dipole?
If you're looking for me, you're probably looking in the wrong place.

gil

QuoteWhere is my thinking wrong considering the rat tail set-up as a 2m dipole?

Pretty much...

Gil.

White Tiger

#14
Anyone ever used a "thru the window" coax jumper (feed line comes into the window, jumper has coax connectors on both sides, connect outside portion to the coax, the jumper is flat with copper wires enclosed/encased, then an aluminum window is lowered and locked, then the 3' coax jumper is connected between the "inside" portion of the "thru the window" connector and the radio) with an HF antenna?

It's getting cold outside and the Frau has lost the desire to put up with the coax coming through a semi-opened window...and will NOT approve of a plan to drill thought "her" wall.

I don't mind drilling though the wall anyway...but I wondered if the the "thru the window" jumper might not help to avert a conflagration...
If you're looking for me, you're probably looking in the wrong place.