My new GMRS antenna

[cistercian]

I put up my gmrs antenna today. A friend gave it to me for free. It is a 3DBD gain Laird that is perfect for 462 Mhz. Great match
on my AA-600 rigexpert. It is not made for 467mhz and has 1.9 to 1 there. Even so reception is much better than I had with my
Comet GP3 ham antenna which has 5.1DBD at 440mhz...and is fed via 100 feet of LMR400. The new antenna is lower and mounted right on
the roof on a drain vent. Feedline is 20 ft of LMR600 equivalent...the cheapest I could find. Unlike the other antenna I am using a N type bulkhead fully a foot long to get thru the wall. Holy cow does it hear well now! (Laird FG-4503) I am using the comet mount I saved from
when I installed my GP3.)
I don't have a "base" radio. I am just using a Wouxun KG-905G. It has a very good receiver. I am set for excellent local coverage!

The antenna has a clear view of the horizon. I am amazed at how well it works.

 

[ENGINEERCARL1]

I put up my gmrs antenna today. A friend gave it to me for free. It is a 3DBD gain Laird that is perfect for 462 Mhz. Great match
on my AA-600 rigexpert. It is not made for 467mhz and has 1.9 to 1 there. Even so reception is much better than I had with my
Comet GP3 ham antenna which has 5.1DBD at 440mhz...and is fed via 100 feet of LMR400. The new antenna is lower and mounted right on
the roof on a drain vent. Feedline is 20 ft of LMR600 equivalent...the cheapest I could find. Unlike the other antenna I am using a N type bulkhead fully a foot long to get thru the wall. Holy cow does it hear well now! (Laird FG-4503) I am using the comet mount I saved from
when I installed my GP3.)
I don't have a "base" radio. I am just using a Wouxun KG-905G. It has a very good receiver. I am set for excellent local coverage!

The antenna has a clear view of the horizon. I am amazed at how well it works.

Laird is a solid antenna. I've run them on NMO mounts for decades...back when they were straight Larsen.

If it's perfect at 462 and a little high at 467, then the antenna is a smidge long. With a VNA or a good SWR meter, you could ease that thing into resonance at 464.5 and have the same SWR for TX and RX on repeaters and simplex.

EC

 

[prcguy]

Laird is a solid antenna. I've run them on NMO mounts for decades...back when they were straight Larsen.

If it's perfect at 462 and a little high at 467, then the antenna is a smidge long. With a VNA or a good SWR meter, you could ease that thing into resonance at 464.5 and have the same SWR for TX and RX on repeaters and simplex.

EC

Larsen has been affiliated with Radiall and Pulse, I don't think they were ever associated with Laird. Laird and Antenex merged at some point and are also listed with TE connectivity.

 

[cistercian]

Laird is a solid antenna. I've run them on NMO mounts for decades...back when they were straight Larsen.

If it's perfect at 462 and a little high at 467, then the antenna is a smidge long. With a VNA or a good SWR meter, you could ease that thing into resonance at 464.5 and have the same SWR for TX and RX on repeaters and simplex.

EC

It is glued shut! I intended to adjust it but whatever stuff they used is white and no joy at all! It's a base model 44 inches tall in a UV
resistant radome. It exudes quality. I don't want to put a bigger antenna up where it is so the windload on the vent is kept nice and low.
It is made for 450 to 460 mhz but has better swr @ 462.550 than any where in it rated frequency.
I am listening right now and on local in the city traffic it is amazing. The GP3 is better at hearing very distant repeaters...but only marginally so on a few. It's nearly twice as high though.

 

[mmckenna]

It is glued shut! I intended to adjust it but whatever stuff they used is white and no joy at all! It's a base model 44 inches tall in a UV
resistant radome. It exudes quality. I don't want to put a bigger antenna up where it is so the windload on the vent is kept nice and low.
It is made for 450 to 460 mhz but has better swr @ 462.550 than any where in it rated frequency.
I am listening right now and on local in the city traffic it is amazing. The GP3 is better at hearing very distant repeaters...but only marginally so on a few. It's nearly twice as high though.

You can't tune those.

If it's made for 450-460, then it's probably tuned closer to 455MHz, which is common for LMR use. If it's giving you low SWR at 462, that's a good sign, but it is not surprising that the SWR is starting to swing up by 467MHz.

You can get these antennas that are designed for 460-470MHz, which would give you lower SWR on GMRS.

But don't get hung up on it. 1.9:1 isn't going to hurt your radio.

 

[cistercian]

I used a loss coax loss calculator I found online Coax Loss Calculator | KV5R.COM

With 100 ft of LMR 400 power loss was 48% @ 465mhz. Power loss through 20 feet of LMR 600 is 7%.
With the difference in gain of the antennas factored in the new install has a trivial .6DB advantage.
But the difference in practice is epic. I am sure the antenna pattern differences account for the change.

 

[cistercian]

You can't tune those.

If it's made for 450-460, then it's probably tuned closer to 455MHz, which is common for LMR use. If it's giving you low SWR at 462, that's a good sign, but it is not surprising that the SWR is starting to swing up by 467MHz.

You can get these antennas that are designed for 460-470MHz, which would give you lower SWR on GMRS.

But don't get hung up on it. 1.9:1 isn't going to hurt your radio.

Yep. They are expensive and this one cost zero dollars. Bang for the buck is epic.

 

[cavmedic]

What’s it linked to and did the FCC come knockin?

 

[mmckenna]

Yep. They are expensive and this one cost zero dollars. Bang for the buck is epic.

Exactly. It works and the price was right. Like I said, 1.9 swr isn't going to hurt your radio.

 

[cistercian]

You can't tune those.

If it's made for 450-460, then it's probably tuned closer to 455MHz, which is common for LMR use. If it's giving you low SWR at 462, that's a good sign, but it is not surprising that the SWR is starting to swing up by 467MHz.

You can get these antennas that are designed for 460-470MHz, which would give you lower SWR on GMRS.

But don't get hung up on it. 1.9:1 isn't going to hurt your radio.

The stock antenna tests at a hair over 2 to 1 so I don't care too much.
The Nagoya 771G is incredibly good and a serious upgrade. Better than 1.2 to one worst case. It is, by far, the best rubber duck type
antenna my AA-600 has ever met. Highly recommended!