Backpack Antenna, coax, radials, and tigertails

[WRFP399]

I tried doing a search a few different ways but found no results. 

If I take a Nagoya NA-771G and have it "mounted" on a backpack with 2 feet of RG174 leading to it do I need a radial or "tiger tail" or does the outer braid of coax take care of that?  When I am hiking this often the setup I use and I am just making sure I am not missing something.

[Lscott]

42 minutes ago, WRFP399 said:

I tried doing a search a few different ways but found no results. 

If I take a Nagoya NA-771G and have it "mounted" on a backpack with 2 feet of RG174 leading to it do I need a radial or "tiger tail" or does the outer braid of coax take care of that?  When I am hiking this often the setup I use and I am just making sure I am not missing something.

The antenna needs a ground plane, or the equivalent, to work. I've tested a lot of hand held radio antennas with and without a ground plane. Just about everyone resulted in a crummy match except the 1/2 wave types. I had thought that a good ground plane would yield a  good match, nope. Some tested better when stuck on the back of my hand, see sample photo, verses a large sheet metal ground plane. I'm guessing the antennas are specifically tuned to use the small ground represented by the metal body of the radio and coupled into the users arm while hand held.

I wouldn't depend on the coax shield either. You get RF on it which feeds back into the radio resulting in "undesirable" operation.

For the NA-771G you can try a tiger tail.  I'll suspect as the tail moves around the match will change a lot too. If you have a backpack with a good sized metal frame that might work as good if not better than the tiger tail.

483039407_AmateurRadioPedestrianMobileHandbook.pdf

[WRUK799]

Why not just use a hand mic with it?


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[Borage257]

Roll up jpole mounted on a fiberglass driveway marker. Lash it to the side of your pack.

[Photoman5k]

I run my radios in a similar fashion and I run tiger tails on all 3 of those radios in my experience it helps. A freind of mine ran the exact same set up as me same radio, same antenna, same coax connector between radio and antenna just no tiger tail and the difference in performance between mine and his was noticeable enough for him to add a tiger tail. They are easy enough to make, don't waste money buying one just make it yourself. 6.5in piece of wire a ring terminal and some shrink tube is all you need. Normally attach mine using one of the screws for the belt clip.

[AdmiralCochrane]

I found the performance of the tiger tail was improved by running it perpendicular to the antenna and facing to or away from the other antenna.  Straight down (inline with the antenna) or outside of the angle directly to the other station, I could not see any performance increase. 

[Photoman5k]

On 10/23/2022 at 9:51 AM, AdmiralCochrane said:

I found the performance of the tiger tail was improved by running it perpendicular to the antenna and facing to or away from the other antenna.  Straight down (inline with the antenna) or outside of the angle directly to the other station, I could not see any 

Not the first time Ive heard that but never really played around to find out. When I have the radio on at home I have to put push the tail  up so it is perpendicular to the antenna or the radio won't stand up but I've never noticed a difference with it that way compared to the tail facing down. When it's in the radio pouch the tail is usually facing down. I'll have to play with it and actually pay some attention to it and see what happens.