Tram 1185 Mag Mount

It’s a question I clearly remember from the technician exam, “What is a good reason not to use a “rubber duck” antenna inside your car?”, the answer being “Signals can be significantly weaker than when it is outside of the vehicle”.
It makes perfect sense, you’re in a big metal box, of course it’s not going to work as well. I’m still researching mobile radios for my car and as such I’m still using my handheld Baofeng radio. However, like the question suggests… the stock rubber antenna doesn’t work that great when you’re driving around. To solve the problem I started looking for an antenna I could mount to my car. I’m currently leasing an FRS so anything permanent wasn’t really an option for me. The easiest solution was to opt for a magnetic mounted antenna.
It worked out quite nice since I have it sitting on my trunk, feeding in through the trunk lid at the top, and then running into the front of the car. Since the backseat lays down and provides easy access to the trunk it was a breeze to run the feed-line and tuck everything neatly away.
I bought a Tram 1185 Amateur Dual-Band Magnet Antenna, which connects to a radio via a PL-259 connector. However I planned on using this with my Baofeng UV-5R which uses a Female SMA connector. To solve this, in addition to the antenna, I also purchased a SMA Female to UHF Female RF Adapter. This solved that issue but then presented a new problem. While everything connected together fine and was working great; there was about a half inch exposed gap at the antenna connection point.
From my ham study questions, I know moisture can be a big factor in poor radio performance. So I wanted to seal the gap but still be able to easily remove everything to use the stock antenna.
Off to the hardware store I went! After a few minutes and a little trial and error, we found a pack of two rubber orings that fit perfectly around the inner edge of the adapter. When stacked on top of each other they completely sealed the gap with a nice snug fit. A dab of glue to hold the two of them together, they now sit on the adapter in the car for easy use.
Baofeng Adapter Gap  Orings  No gap  Box

This Post Has 2 Comments

  1. Jim

    I just added your page to my bookmarks. I really enjoy reading your posts. Thank you!

  2. Kyaw Zeyah Mr.

    Dear Jon,
    Let me share my experience when I using UV5r in my car.
    ( 1 ) Connect the mag mount antenna ( diamond antenna for vhf-uhf one )
    ( 2 ) Then connect the SMA Fm adapter to radio n then join with diamond antenna.
    ( 3 ) But i’ve found out is that my radio receiving sensitivity is drop.
    ( 4 ) For example when i tune the marine frequency 156.800 with original rubber antenna,it’s OK and but with outdoor ant or diamond ant ,the answer is “no”. Then I’ve took out these outdoor ant and put back it’s own rubber ant it’s become OK n I could hear Marine conversation again.
    I’ve no idea Why.
    I also have IC V80 but that one is OK.
    Kindly advise what is happening.
    With Ths n Best Regards,

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