Radio Troubleshooting Assistance Requested

[Deleted member 48574]

Hey folks,

So I've got myself a Yeasu FT1900 radio. It's a pretty nice little unit as it's able to receive a bunch of commercial bands, which is handy when exploring some of the logging roads. In theory, and the reason I purchased it, is so I can hear truckers who are supposed to call out their mileage markers, and the frequency of particular roads is on a sign at the head of the road. So, it's basically a glorified scanner that, when I go through the process of getting my HAM license (this month), I can then use for comms.

Here's my situation.

Originally I had the antenna, which was the cheapest of cheap crap, mounted on the tailgate of my Jeep with the cheapest of cheap coax running through the tailgate, under the carpet, to the radio which is in the center console.

I had it set up that way since last October, and this entire time, i've assumed that a) truckers don't call out markers and b) no one in my city uses a HAM.

So, one day I forgot to remove my antenna before opening my RTT. Bent antenna!

That gave me the excuse to upgrade, so on my day off on Monday (which was a rarity) i went to a local radio shop. The guy there taught me a LOT about radios, and at the end of the day, I bought a new antenna, new Coax, and a new mount. He was surprised that I hadn't hear anything since last October. He then attached a mag antenna to my radio to demonstrate, I was blown away by how much people were chatting -- seriously it was a ton of people coming in as clear as day.

So I've got that rigged up now -- antenna, new coax, all into the radio. And still all I get is static.

The radio manual says to turn the squelch up until it just silences background noise; for me to do that I have to turn the squelch basically 90% of the way. And I have yet to hear anyone talk on any LADD stations, with over 3 hours of testing.

Now my fiancee heard some chatter coming across a large steel bridge, but nothing in and around the city.

So my question is:

How do I troubleshoot this particular problem? Any experts out there that can suggest a method of attack to figure out what's wrong?

I should mention that I can usually hear the weather channels reasonably well, but with background static also. At the moment this radio kit is basically $500 dollars worth of a white noise machine.

Any help would be much appreciated.

Cheers
Craig

 

[4x4junkie]

Do you have (or know someone who has) another radio you can try communicating with? (or at least see if you can receive a signal from)?
Otherwise I would suggest getting a SWR meter to see if the antenna you have is actually working correctly (maybe the coax got damaged?). At the very least I'd have that shop you went to take another look at your system (having to turn the squelch up most the way on a FM transceiver to silence the noise also seems a bit unusual. Unless an actual signal is present, they almost always will squelch at around a 30-50% setting).

 

[Deleted member 48574]

Thanks 4x4 junkie! I unfortunately don't have anyone in my locality that I know who is also into HAM but have put some messaging out looking for someone to help.

I'll see about picking up an SWR meter. It does seem odd to have to turn the squelch up so high. It suggests to me some kind of major interference but I don't know where it'd be coming from. I am wondering if an errant electrical gremlin elsewhere in my jeep is causing interference.

I will also try to get back to the shop -- sadly his hours are the exact same as mine so getting away from work is tough.

Regards
Craig

 

[1911]

You need to look at your antenna and coax with an antenna analyzer, but my first suspicion would be a bad connection in the coax or an unsuitable antenna for the mounting location. Exactly which antenna do have, and where is it mounted?

 

[Deleted member 48574]

1911 - the Antenna brand escapes me at the moment but it's mounted on the fender via a stainless steel mount.

I managed to get a few hours off today so I ran into the store. The guy there pulled out the antenna tuner and ended up cutting 1.5 -- nearly 2, really -- inches off the antenna.

It's coming in nice and clearly now, for the most part. Now to get my license and test this thing out properly!

Thanks for all the help, everyone.

Regards
Craig

 

[Borrego60]

Might open up the radio and see if there is a cold solder joint where the antenna cable comes into the radio and to the board that connects it. A small crack can really make a mess of things.

 

[taugust]

You might also look at your power connections and grounds. Ideally, you should hook the radio directly to the battery through positive and negative fused leads. The body of the radio should be connected to the vehicle chassis with a ground wire or braid (Having said that, my radio in my Jetta creates noise when properly grounded). Also, check the contact at the base of the antenna to the mount. Depending on the type, some have a thin metal "spring" contact that sometimes will make poor contact. Also, make sure the mount is well grounded to the frame (don't assume that good contact with the body is a good ground). You didn't say whether the noise is with engine on or engine off. If it is noisy with engine off, then there may be local interference. Try a different location. If it is with engine on, you alternator or ignition system could be generating the noise. Look into filtering.

I highly recommend finding someone with an antenna analyzer that can hook up and tell you how your antenna system is doing. I have found that properly setup antennas will "go out" after a while. It is good to regularly check your antenna for proper SWR.

You don't say where you are located. Let us know and someone nearby might chime in to help. Good luck.