G4 With Mobile NMO Antenna

[Floridarailfanning]

Does anyone have any experience using the G4 or G5 with an NMO antenna for mobile use? I keep my G4 in the car and will occasionally hit dead spots on the TACN system using a stubby 800-900 Motorola antenna, so I am considering installing an NMO antenna. I have been looking at the Larsen LPT700/800NMO and the Larid TRAB7603. Any advise or suggestions about the antennas or coax would be appreciated.

 

[N6ML]

You should be careful about the SMA connector when using anything other than the Unication antenna (including the Motorola ones). You could damage the center pin on the connector otherwise. For external antennas, I use a modified BNC adapter. It was sold for use with Baofeng handhelds, and has a skirt around the SMA part, but there's too much skirt for the G5, so I "machined" it down until the SMA connector inserts exactly the same amount as the stock antenna. This provides a good RF connection and mechanical stability, and doesn't squish the pin.



My current mobile antenna is really high-tech .. it's a piece of Romex wire stuffed into a SO-239 mag-mount



In practice, I generally don't bother with external antennas on the G5 (use the above sometimes with the SDS100) - the G5 does well enough with the stock antenna, clipped to the visor above my head.

 

[Floridarailfanning]

I am aware of the issue with the center pin, but so far when switching back to the stock antenna I have not experienced any problems. Also, I agree that usually the G4 works well enough with the stock antenna, but I figured adding an external NMO antenna might be worth it since I only use it in the car.

 

[Prospect62]

Wondering if anyone else has tried this and what the results were. Planning on buying a G2 soon and connecting it to my existing VHF NMO antenna in my vehicle (after I toss my analog GE Orion ) to improve performance.

Just curious.

 

[krokus]

Does anyone have any experience using the G4 or G5 with an NMO antenna for mobile use? I keep my G4 in the car and will occasionally hit dead spots on the TACN system using a stubby 800-900 Motorola antenna, so I am considering installing an NMO antenna. I have been looking at the Larsen LPT700/800NMO and the Larid TRAB7603. Any advise or suggestions about the antennas or coax would be appreciated.

Have you considered one of the Remtronix antennas?

 

[Floridarailfanning]

Those Remtronix antennas look interesting and I'll keep them in mind. But, since updating the frequencies for the Black Road site I haven't hit any dead spots. The addition of the new Oak Ridge site also improved the RX coverage quite a bit.

 

[policefreak]

I use my G5 with a Wilson 800mhz magmount antenna and also sometimes the Larsen Tri-Band antenna. While I get more gain with the Wilson one (after all it's just made for 800mhz) I also get a few dead spots around some cell towers. Same thing when I attach a Remtronix 800mhz portable antenna. There are areas where less is more. Other times I can clearly pick up 800mhz P25 systems up to 30 miles away with one of these.

 

[GTO_04]

The Remtronix antennas are excellent IME!

GTO_04

 

[krokus]

Those Remtronix antennas look interesting and I'll keep them in mind. But, since updating the frequencies for the Black Road site I haven't hit any dead spots. The addition of the new Oak Ridge site also improved the RX coverage quite a bit.

I have one on a G4 at one of our fire stations, for the house bells. It eliminated the signal loss issues. (This was just before Unication introduced their gain antenna.)