Tram Trouble

[Ensnared]

I have used two different NMO Tram antennas, one with 58U and the other with 58AU. Despite my best efforts to avoid crimping the coax, both are dead.

I am curious. What are my options? I cannot see any obvious signs of damage. The BNC plastic housing is clearly intact.

Is it possible to replace the NMO part without having to buy a whole new antenna base?

 

[mmckenna]

How did you determine where the issue is?

I did an install on my dads new pickup and he showed up with a pre-terminated Tram NMO mount. I expressed my disappointment with his choice and offered him one of my Larsen kits. But he was OK with it...
Anyway, I had to cut the end off the cable anyway to route the coax. I crimped a new connector on the end.

The coax connection at the NMO mount seemed OK. The coax looked like most other RG-58's.

I had the last foot or so of cable laying on my workbench for a while. One evening I decided to cut the molded strain relief off to take a good close look at the connector. Not surprising, I found what I'd figured I'd find. It was the absolute cheapest/flimsiest connector I'd ever seen. Very thin metal. The crimp was a single dot in the outer sleeve that looked like it had been made with a center punch. Not a full crimp. The center conductor solder job looked OK, but not sure about the inside.

So, my suggestion would be to cut the connector off the end of the coax and replace it with a real connector, unless you know for sure the issue is at the NMO base.

 

[Ensnared]

I had one of those Larsen NMO rectangular base mounts, but I opted for the Tram because of the rubber boot on the magnetic base. If I can, I will find one of those solderless twist-on BNC for the time being to determine if this is the cause. Since I am an idiot with an iron, I selected the 58U for this very reason. I can make it work until I can get down to the radio shop in Troy, Texas. Thanks for your input. Do you happen to know of any rubber-booted NMO mounts? I saw one with Laird, but I don't know if this would work.

 

[mmckenna]

Do you happen to know of any rubber-booted NMO mounts? I saw one with Laird, but I don't know if this would work.

No. I've got one of the old Larsen rectangular mounts, but I only use it for temporary testing. I long ago switched to permanent mount NMO's on all my own personal vehicles.

 

[Ensnared]

mmckenna: Sir, man were you spot-on. I took your advice and jumped off the bridge. I found a solderless connector. That BNC housing was a piece of crap! Flimsy. When I cut the end off, there wasn't even any center conductor showing. So, I trimmed it back a bit and screwed that puppy on. Bingo. It came in like gangbusters. I will take the one with 58AU to the professionals to use as a spare. I hate braided center conductors because they don't work well with closed doors. Then again, it might also be the BNC end.

Looks can surely be deceiving. I thought that molded plastic protection would be bulletproof. Man I was wrong.

One more thing. I have the Larsen Triband antenna. When I screwed the antenna off the base, there were drops of moisture. Do you have any idea on how to fix this? Would silicone help? Or, maybe I need to tighten some things.

God bless you buddy! Thanks.

 

[mmckenna]

mmckenna: Sir, man were you spot-on. I took your advice and jumped off the bridge. I found a solderless connector. That BNC housing was a piece of crap! Flimsy.

I'm glad that worked.

I try to steer people away from the Tram/Browning and other Chinese products. Just not worth the minimal cost savings.

One more thing. I have the Larsen Triband antenna. When I screwed the antenna off the base, there were drops of moisture. Do you have any idea on how to fix this? Would silicone help? Or, maybe I need to tighten some things.

The antenna should have come with one of these. If it didn't, get one. They work.
https://www.theantennafarm.com/catalog/larsen-rgss-5379
Like I mentioned above, 30 years of Larsen antennas, never had an issue. The gaskets work. However, periodic preventative maintenance should be part of it, too. Pulling the antennas off, cleaning under the gasket, clean mating surfaces, check for corrosion, etc. Occasionally put some Armor-All on the gaskets to keep them in good shape.

God bless you buddy! Thanks.

Thanks, I need all the help I can get.

 

[Ensnared]

I am a former Antenna Specialist man. I remember one of my favorites. It was a trunk lip mount and it had something called a "microchoke" which was like a hollow black tube that pulled in 800 mhz.

Now, let me get this straight. Are you talking about the "Screaming Eagle" manufacturer, Browning? I was unaware they sold out to Chinese crap tactics. Wow.

Now, I will have to admit, I had no earthly clue that that type of maintenance was needed for these fine antennas. I will get the gasket and disassemble the antenna for maintenance. It has been a champ.

Back to the Tram. The rubber boot was brilliant. My wife does not like any scratches on her new car. I have a Tram 3500 for CB with the same rubber boot. I must admit, it does the job protecting the paint from scratches.

The antenna I always wanted, but was too cheap to buy was one of those Austin fellas. I don't know if these are still being made.

When I had my magnetic moun K40, it ruined the paint on my other vehicles.

Thanks again.

 

[mmckenna]

I am a former Antenna Specialist man. I remember one of my favorites. It was a trunk lip mount and it had something called a "microchoke" which was like a hollow black tube that pulled in 800 mhz.

Now, let me get this straight. Are you talking about the "Screaming Eagle" manufacturer, Browning? I was unaware they sold out to Chinese crap tactics. Wow.

Now, I will have to admit, I had no earthly clue that that type of maintenance was needed for these fine antennas. I will get the gasket and disassemble the antenna for maintenance. It has been a champ.

Yeah, Tram and Browning, big CB names from the 60's and 70's was sold out to a company in the US that is now selling the cheap Chinese antennas. Clever trick, buy a name known by hobbyists, then sell knockoff antennas. They always are at some of the big radio trade shows, but they don't seem to get much attention.

As for antenna maintenance, I usually remove my antennas after washing the vehicle. I'll clean out under the gasket, make sure the contacts are clean, and periodically wipe everything down with alcohol. The gaskets periodically get some armor all to keep them looking new.

I've had to fix a number of corroded out antennas at work. All it takes is a few minutes to give them some attention and they outlast the vehicle.