Mobile Antenna Mounting

[Matthew Sweet]

I'm sorry, I wasn't clear... MFJ meaning the SWR meter. Just making sure there's a 1:1 SWR before clamping the mount down permanently. He obviously wouldn't be using it for transmit purposes. Could be a bit of a time saver if he mounts it, finds he can't get a good tune on it, then sees some crazy SWR number.

The antenna will exhibit different SWRs at different spots on the vehicle. Finding a spot with lowest VSWRs and then fine-tuning it would be ideal, but not always an option. The meter is indispensable here, especially with a 1/2 wave antenna.

 

[B. Dean Berry]

SWR Meter. I have to get one of those. As I've pretty much only used commercial NMO antennas for years, with few exceptions, I've just used the included cutting charts and been mostly alright.

 

[Matthew Sweet]

SWR Meter. I have to get one of those. As I've pretty much only used commercial NMO antennas for years, with few exceptions, I've just used the included cutting charts and been mostly alright.

When it comes to just pumping 10W into a local repeater for a weekend ragchew, no worries. Things get critical when you're looking to hit distant repeaters at 50W and up. To be honest, I'd be a terrible amateur radio operator if I said you don't need an analyzer for mobile antennas. The truth is, you do, especially when using antennas that utilize the vehicle as a magnetic ground plane.

The antenna analyzer is a common component among hams, as I'm sure you know. The great part about that is, a simple "Hey, anyone got an antenna analyzer they could bring over?" usually is met with enough volunteers you could take your pick.

 

[B. Dean Berry]

I've been installing commercial/public safety for about 18 years now, and have rarely ever used one. Usually, they only come into play for me when troubleshooting problems.

Then again, there's not a lot of guesswork involved when you're talking about an 800MHz trunk system. The system is there, the radios are tuned and programmed, and everything gets the same 3" long 1/4 wave antenna.

 

[B. Dean Berry]

That being said, I had an interesting antenna issue last week when trying to get into a distant VHF repeater that I discussed with @Drew Terril . Apparently, antennas don't like bends of any kind.

 

[Matthew Sweet]

Some of them do, believe it or not.

W5ALT Using Bent Dipoles

Learn various ways of using dipole antennas in various configerations and shapes.

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