Amateur (Ham) Radio BS and Callsign Thread!

I wish I had friends that wanted to offroad/camp and talk on radios at the same time...

 

IIRC, since you already have your license you can immediately use your general class priveleges once you pass the test, you just add an extra letter designator to your callsign indicating you are waiting to be officially licensed as a general class in the system.

The only people the shutdown effects are those without a callsign.

 

Very cool, kind of the same for me. Everyone around here has always used CB, but in the last year or so it seems like everyone bought a baofeng. Unfortunately most people just use it on GMRS frequencies illegally I think, so figured it would be cool to bring some sanity and introduce some of the cool ham stuff.

I'm just barely beginning to figure out the best mobile rig to go with, lots of research to do...

 

That's true. Just toss the AG on there.

 

That's actually a question on the general. <callsign> AG (acting general i think?). You just need the certificate paperwork they give you when you pass.

 

Haha I knew that too. I'm just sleep deprived from 3rd shift. Plus I've been watching detailed reveiws on HF radios for 2 hours. My mind is scrambled. Tossed a bit of D-RATS in there for good measure

 

That's why Im getting into HF. More string. I'm finding that a lot of the guys in the local clubs are old off roaders too. I'm counting on getting some to come out with me. Plus there are field days as well. Maybe even drag friends along for SOTA events ? I'm looking forward to our 200 miles of back country fun and operating from a clearing on a hillside circa middle of no where. Few ham buddies from different states will be going . @Subway4X4 just doesn't know it yet. 2 tags in one day . Be flattered

TM-V71a. Kidding. I'm bias.








But seriously.

 

Any ideas what could be causing this interference with the SBB-1? It’s mounted on a ditch light bracket on the passenger side.

Pic 1) engine off SBB-1 antenna. Nothing showing up on the meter.
Pic 2) engine ON SBB-1 antenna meter maxes out and bounces around
Pic 3) engine ON SBB-7 antenna and the meter is much lower.

 

So you have any LED lights? I have a cheap set of pods that had no problems initially but over time have started causing interference when turned on with the regular FM radio and HAM radio.

 

I do but not turned on.

 

Grounding issue with that antenna maybe ?

 

Grounding the antenna bracket would be my first guess as well.
Also, did you use original power wire harness? Extentions? Additional fees under the hood?
All those could potentially accept interference.
Also, unplug any USB chargers and re-check. Some cheap ones were interfering with my CB ( since I don't use them anymore I cannot verify with ham)

 

It might be worth a second test to see if the noise comes with the key=on (engine=off) or key=on (engine=running).

Once you're comfortable with the antenna's grounding, a look at where you're getting power for the radio might be a good second stop:

• Are you direct to the battery, or running off of some other circuit for your positive
• What about the radio's negative (and / or supplemental RF ground)

 

SBB-7 vs SBB-1, I'd check that the mount is well grounded and you've provided a suitable ground plane for the antennas to work against.

Consider that the SBB-1 is a plain 1/4 wavelength (on VHF) and the SBB-7 is a loaded gain antenna with (I think) a matching network in the base. So the SBB-1 will be absolutely reliant on the mount and a plane to act as a counterpoise while the SBB-7 is probably less so. This means any noise being coupled via the ground or is common mode will be more obvious with the SBB-1.

If I had to guess a root cause here it's that the ditch light brackets aren't really doing you much favor on a 1/4 wavelength antenna and the RF is finding whatever circuit it can back to the radio, over the coax shield probably. Which means it's just happy to couple noise from every electronic device your feed line runs near, the dash radio, the ECUs, LCD screen backlight drivers. There's a ton of places generating RF noise in our trucks.

You might be able to use a common mode choke or just snap on some ferrite beads to quiet it down but the real fix is a better mount (at least make sure paint is scraped back and you have conductivity throughout) for the antennas or use antennas that are ground plane indifferent.

 

BTW, just for reference I run ditch brackets for my antennas. I use two 1/2 wavelength antennas, a Larsen NMO2/70 and a Laird VHF whip. Neither of them need a ground plane to work. I've tried a 1/4 wavelength whip on the VHF radio (it's an APRS radio) and never have been able to get it work satisfactorily.

 

Sbb-1 is ground dependent, sbb-7 is not. That's why it picks up less noise. Tacoma is the worst RFI generating vehicle I've had in 25 years of ham operating. I have not been able to make any ground plane antenna work on my 2017. If you think vhf is bad, you should hear HF. it's like a buzz saw no matter what I've tried.

 

Thanks for the help everyone. Found out the culprit is my dash cam power wire. With it unplugged everything is nice and quiet. Gonna try some ferrite chokes on it and see if that helps.

Have a ground strap going directly to the ditch light mount so it’s grounded very well.

 

Glad you got it figured out. I came here to mention a ground strap. I've got a CB antenna on the passenger side and an SBB-5 on the driver's, used ground straps on both and have had 0 issues (so far)

 

Is there any reason not to run an antenna near the tailgate where I would normally put my CB antenna? I know there's no ground plane there so I assume that I'd need a particular type of antenna?

 

I ran a Diamond SG7900 above the passenger taillight and it worked GREAT! Low SWR and no engine noise. Although I have LMR400 coax running to that location. I have since put a LMO mount through the roof for VHF/UHF, and put a CB antenna in that location on the LMR400 with very little engine whine at higher RPM's. It can be done with the right coax and antenna. I also have ground straps all over the vehicle. Fenders to frame, 2 on the cab to frame (both sides), 2 from the bed to frame (both sides) and one on the tailpipe to frame.

The SG7900 on a light mount above the taillight.