Jump to content
  • 0

which ht antenna?


WRUG770

Question

4 answers to this question

Recommended Posts

  • 0
2 hours ago, WRUG770 said:

I have the baofeng uv-9g and need a upgraded antenna . does anyone know what to buy ? I need to hit a repeater around 30-40 miles away.

I'd suggest a 40-50 foot extension ladder but you may need guy wires and ground stakes to keep it from tipping over when you climb above the roof ledge you leaned it against (eg: roof ledge at 25 feet means you have 15+ feet of the ladder /above/ the roof ledge, and will be standing about 35-45 feet up).

VHF, and even more, UHF is considered "line of sight". For the most part, if you can "see" the repeater you can probably hit it even with 2W middle power from an HT. If you have a forest between you and the repeater, you are in trouble -- all that moist greenery tends to absorb UHF (less so for VHF -- but the larger wavelength of VHF has trouble getting through buildings, hence why many big city Fire departments are UHF and up; UHF wavelength gets through window panes and doorways.

Any antenna you pick will need to have a gain over dipole (ie: a positive number with dBd behind it; if the antenna spec shows dBi, you need to convert to dBd: dBi - 2.1 => dBd as I recall). A 3dBd antenna will have an effective radiated power twice that of a dipole -- but there is a trade-off! The higher the gain, the narrower the emitted "beam". A dipole (or quarterwave with ground plane) is essentially a donut pattern with the antenna going through the hole. A really high gain vertical will have a pattern closer to a large diameter pancake. ADDENDUM: these HT antennas are going to be, for the most part, long/skinny whips -- 2 foot or more. This makes them somewhat annoying if you carry the HT on your belt -- any movement will cause the whip to... well... whip you in the back or side. The alternative is center loaded telescoping antenna -- but those have no give, any side forces on the antenna will transfer directly to the antenna connector, and SMA connectors aren't all that strong.

This could be a problem -- if the repeater is on a tall mountain, you may have to tilt the radio so the "pancake" rises to the repeater, otherwise your signal is just going to dead-end on the base of the mountain (the donut dipole has enough signal going up and down to maybe reach the repeater without tilting).

Being in the open helps. If you are inside a vehicle, you might want to consider a mag-mount (or window mount) with adapters to go from the common PL-259 down to the antenna jack (I recommend NOT putting an SO-239<>SMA adapter directly on the radio -- the stress could cause solder breaks; use a THIN 12-18" SMA<>SMA coax jumper and then add the adapter to the end of that).

If inside a building, you may want to stand near a window facing the repeater. I have a 2m repeater about three-four miles from me... But it is on the other side of two forested hills, and I live in a house with a metal roof and aluminum siding. I can break repeater squelch with no problem, but I was told that my voice was unreadable even on high (5W) power!

 

Link to comment
Share on other sites

  • 0

thank ya'll for the input.I do live on the top of a mt. but not sure where the repeater is . 

 I was looking at the (nagoya-na-320a) or a (diamond rh77ca) but I see now they prob. won't work.

I'll look into some base antennas was prob going to get a base station anyhow . thank ya'll

Link to comment
Share on other sites

  • 0
On 9/5/2022 at 5:33 PM, WRUG770 said:

 I was looking at the (nagoya-na-320a) or a (diamond rh77ca) but I see now they prob. won't work.

The NA-320A is tuned for Amateur bands; the nearest equivalent for GMRS is the NA-771G.

Same problem with the Diamond -- tuned for Amateur bands.

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Answer this question...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.