Help With Mobile Antenna Reception

[ocjesse]

I'm new to scanning and recently purchased a Uniden 996t scanner for my truck. I wired a Firestick Scanner antenna to the Uniden with low loss cable. For some reason my reception is poor (I live rural without much activity and can only test on 150 - 155MHZ). If I connect the uniden supplied antenna to the scanner in my house reception is good.

I did tons of research but can seem to answer some basic questions myself, so I'm hoping to get some good feed back.

Below is a link to a photo of the antenna locations, to the left is the Firestick, to the right is a second antenna (Austin Spectra) which I have separately wired into the cab hoping that It would work better, but unfortunately they both perform poorly. The other antennas are for wireless broadband and XM, I tried removing them thinking there was some sort of interference, but the results were the same.

http://www.opencube.com/tundra/d2.jpg



Questions:

1: Where the coax connects to the antenna stud, I used a bolt through a ring which I connected to the inner wire of the coax and verified that the signal goes through to the antenna. What if anything should I do with the outer shielding wire (I cant use a pl259 due to my mount situation, I tried grounding it but that made it worse, I tried wiring it to the stud / antenna and my results were unchanged)?

2: Do I need a ground plane for scanning (I don't have one where it's mounted, the rack an tonneau is not grounded)?

3: Are my antennas to close to the cab?



Any advice is appreciated, thanks in advance.

 

[N0ZQR]

Did you insulate the bolt from the mounting plate? It would help (at least me) if we could see what the bolt/mounting plate looks like.

As far as the other antenna, I am not familiar with that so will need to have someone else help you with that one!

Cool ride otherwise

Ron

 

[ocjesse]

Did you insulate the bolt from the mounting plate? It would help (at least me) if we could see what the bolt/mounting plate looks like.

As far as the other antenna, I am not familiar with that so will need to have someone else help you with that one!

Cool ride otherwise

Ron

I used a nylon washer on each side to insulate it, the bolt defiantly does not contact the metal bracket.

 

[Scandxer]

My opinion is that possibly that metal rack in the back is killing the reception to your Antennas either at the mount bolt like N0ZQR pointed out or just all together blocking or draining reception somehow.

Maybe it's a bad mount spot for that reason.

 

[Scandxer]

If you can't get it worked out you still have glass and magnet mount options..

I mounted a Mobile "Cellular Look-Alike" Glass-Mount Scanner Antenna from Radio shack to the back of my van and the reception is killer.

http://www.radioshack.com/product/index.jsp?productId=2102468

 

[rcvmo]

If memory serves me correct, isn't the firestick a cb antenna? Thus the freq. response is geared for lo-band and your trying to moniotr VHF? Second, I'm sure the firestick center conductor is grounded by a shunt somewhere on the stick itself. That would kill your VHF recetpion in a heartbeat. I used to have my scanner connected to an unused base CB antenna many years ago, it just didn't do justice for freq's beyond 50 MHz. But........it was kick butt for lo-band below 50 mhz .
rcvmo

 

[SAR923]

That shovel probably isn't helping matters any. What is all that stuff, anyway? As a test, go to radio shack and buy their mag mount antenna and try it on the roof. If it doesn't help, you can return it within 30 days but I'll bet anything on the roof and away from all that stuff on the bed cover will help.

 

[ind224]

I see an anemometer, but no Helen Hunt.

 

[blueangel-eric]

That shovel probably isn't helping matters any. What is all that stuff, anyway? As a test, go to radio shack and buy their mag mount antenna and try it on the roof. If it doesn't help, you can return it within 30 days but I'll bet anything on the roof and away from all that stuff on the bed cover will help.

i second that question. what is all that stuff? It looks like an eyesore to me. I've never seen anything like that.