Comet CA-712EFC 460-470Mhz base atenna review

[Riktar]

19 hours ago, GreggInFL said:

Being new to GMRS I'm hoping to eventually collect HTs, a mobile and a base station/repeater.  I have the HTs and am looking at a mobile with a mag mount antenna, which will be a lot shorter than the Comet.  This is the combo I'd like to test in the attic; curious how much attenuation will occur.

Yeah, my attic, like most, is too short for the Comet so it will eventually go outside.

Be aware that most mag mount moble antennas use the vehicle chassis as a ground plane. If you experiment with this make sure you have some type of 'groundplane' to attach the mag mount to. A large baking pan or pizza pan should suffice. I don't recall the minimum diameter you should use but I am pretty confident a 12" pizza pan should work.

[dosw]

2 hours ago, Riktar said:

Be aware that most mag mount moble antennas use the vehicle chassis as a ground plane. If you experiment with this make sure you have some type of 'groundplane' to attach the mag mount to. A large baking pan or pizza pan should suffice. I don't recall the minimum diameter you should use but I am pretty confident a 12" pizza pan should work.

A 1/4 wavelength at 462MHz is a touch under 6.4 inches. Any ground plane is better than no ground plane, I imagine, but using a 14 inch pizza pan would be better.

[GreggInFL]

6 hours ago, WRQW589 said:

A 1/4 wavelength at 462MHz is a touch under 6.4 inches. Any ground plane is better than no ground plane, I imagine, but using a 14 inch pizza pan would be better.

Found a 16" pizza pan and a Nagoya UT-72G.  Time to hit the attic (which must be 140*).

[Riktar]

3 hours ago, GreggInFL said:

Found a 16" pizza pan and a Nagoya UT-72G.  Time to hit the attic (which must be 140*).

I went through this a few summers ago in my former residence. It was 120+ degrees and I spent almost a whole day (This place had a BIG attic) finding the best position to put my antenna. Felt like I sweated a gallon of water before the day was through.

Good Luck!

[WSGF688]

On 6/26/2024 at 3:43 PM, GreggInFL said:

Found a 16" pizza pan and a Nagoya UT-72G.  Time to hit the attic (which must be 140*).

I know this is an old post, but how did the Nagoya UT-72G in that attic turn out?

[GreggInFL]

15 hours ago, WSGF688 said:

I know this is an old post, but how did the Nagoya UT-72G in that attic turn out?

I haven't tried it yet.  It's my mobile antenna and the idea of running cable with adapters for something that will eventually go back in the vehicle makes little sense.  Presently looking for an antenna I can park in the attic as a permanent base antenna.

Any recommendations?  5' - 6' max height.

[SteveShannon]

24 minutes ago, GreggInFL said:

I haven't tried it yet.  It's my mobile antenna and the idea of running cable with adapters for something that will eventually go back in the vehicle makes little sense.  Presently looking for an antenna I can park in the attic as a permanent base antenna.

Any recommendations?  5' - 6' max height.

Comet CA-GMRS

https://www.gigaparts.com/comet-ca-gmrs-base-antenna.html?utm_term=sku-zcm-ca-gmrs&gad_source=1&gbraid=0AAAAAD_py5EKZQxij1cmldY7F8FS3Vn42&gclid=Cj0KCQiAyoi8BhDvARIsAO_CDsBPolyUSP6EAjfHgLTgAmTPj__UDbKhG2y8DMvRLwgdMx9xjiUbKR8aAgAQEALw_wcB

 

[GreggInFL]

19 hours ago, SteveShannon said:

Comet CA-GMRS

https://www.gigaparts.com/comet-ca-gmrs-base-antenna.html?utm_term=sku-zcm-ca-gmrs&gad_source=1&gbraid=0AAAAAD_py5EKZQxij1cmldY7F8FS3Vn42&gclid=Cj0KCQiAyoi8BhDvARIsAO_CDsBPolyUSP6EAjfHgLTgAmTPj__UDbKhG2y8DMvRLwgdMx9xjiUbKR8aAgAQEALw_wcB

 

Aha, 42".  Should have known Steve would nail it.  Thank you, sir!