Noise

[ctvanover]

I know that it has been answered before but I'm gonna aak again. If you can show me the threads I'll look them up.

I am driving a KW T680 sleeper truck. I already know that the factory cb setup sucks. I used a mirror mount, a new Wilson 5000 trucker with 10" shaft with 4" cut from the bottom of the stinger with 1.2 swr, an 18ft single coax with 97% shielding. I have ran a ground wire from the mirror mount to the frame.

This truck has an inverter that powers a small 110v mini-fridge and microwave. The antenna is picking up the noise from the fridge, microwave, and the inverter.

I can unscrew the coax at the mirror mount and the noise goes away. I can turn off the inverter and most of the noise goes away.

My question is do I need a noise filter on the power line or the antenna? Which one is the best for my needs?

Please any and all help will be greatly appreciated. THANK YOU!

 

[9C1Driver]

It sounds like there might not be anything you can do except turn the inverter off. Your only shot will be to address the noise at the source. This will involve adding a filter or choke. I'm sure someone will chime in here on where at your inverter that needs to go.

 

[ctvanover]

I cant turn off the inverter. It powers my fridge.

 

[ctvanover]

How about this filter....

Magnum XLF-20BP 20 Amp Common Mode DC Power Line Noise Filter

1. 

 

[rabbiporkchop]

I know that it has been answered before but I'm gonna aak again. If you can show me the threads I'll look them up.

I am driving a KW T680 sleeper truck. I already know that the factory cb setup sucks. I used a mirror mount, a new Wilson 5000 trucker with 10" shaft with 4" cut from the bottom of the stinger with 1.2 swr, an 18ft single coax with 97% shielding. I have ran a ground wire from the mirror mount to the frame.

This truck has an inverter that powers a small 110v mini-fridge and microwave. The antenna is picking up the noise from the fridge, microwave, and the inverter.

I can unscrew the coax at the mirror mount and the noise goes away. I can turn off the inverter and most of the noise goes away.

My question is do I need a noise filter on the power line or the antenna? Which one is the best for my needs?

Please any and all help will be greatly appreciated. THANK YOU!

I'd put a 4 foot shaft under that wilson to elevate the coil above the cab and narrow the bandwidth which will reduce some noise.

 

[sp5it]

Find inverter which is properly built.
Or: buy 12V fridge and use inverter only when microwave is needed.
Mike

 

[ctvanover]

Yea I have been told to get a true sine wave inverter or a 12v fridge. Is there or are there an antennna that would be better to use?

 

[sp5it]

No other antenna will help. Forget it.

 

[rabbiporkchop]

Yea I have been told to get a true sine wave inverter or a 12v fridge. Is there or are there an antennna that would be better to use?

Not if your noise is from a squarewave inverter.

 

[Slowmover]

Big trucks have no end of “noise”. Here’s how I started with the worst offender in mine

I carry with me in the big truck a chest-style NORCOLD refrigerator/freezer. Can be run off of 12V with a cigar-lighter fitting, or thru the 120V system (inverter) with a converter (NORCOLD optional).

The DANFOSS compressor caused enough RFI when in operation I had to turn off the transceiver, even though I have a pretty high tolerance for noise.

PALOMAR ENGINEERS offers a solution.

- First, from their main page choose Ferrite Core Products.

- Second, choose Ferrite Ring Toroid Cores.

-Third, choose DC Cable Noise Filter for Large Gauge Wire ($44.95).

Now, I can, “sort of”, hear that noise.

They’ve quite a few offerings. My latest truck has a ThermoKing TriPac diesel genset that gives off interference, so I’ll be back to PE to remedy that for when I’m stationary and running the AC off the genset and wish to use the transceiver.

I’ve also bought coax & 12V boxed filters, other toroids, etc. Am pleased with all



.

 

[Slowmover]

How about this filter....

Magnum XLF-20BP 20 Amp Common Mode DC Power Line Noise Filter

1. 

The word on filters of this sort is that voltage to the radio is reduced (without a great effect on noise).

I own one, but haven’t ever installed it.

Below is an example of a filter marketed to DC stereo system problems. Can’t remember brand name offhand, but contributor JesseJamesDallas posted the source several years back.

 

[Slowmover]

That’s the (alternator whine) filter

NAVONE ENGINEERING
12VDC, 10A (10V-18V)
N-700 Electronic Noise Filter

Three-Wire In-line
(Fuse Green to 12V source; send Red to device; Black to Chassis Grnd).

The Dodge Cummins guys were buying this or the N25 to help the throttle position sensor (APPS) to keep TQ converter lock/unlock appropriate.

Mainly marketed to stereo related; listed for amateur radio.

LARGE in size.

$45 approx.

.

 

[Jay Mojave]

Hello All: Noise in the radio can drive one to drinking and worst sometimes, I know I have trouble shot radio noise call RFI (Radio Frequency Interference) many many times over the years. And these RFI problems many aren't easy to fix.

Good call on turning off the inverter and seeing the noise go away. These inverters, converters, Solar Controllers, and other items transmit/radiate RFI into the air, and from the input and output wiring. It might be as easy as wrapping the input and output wiring with mix 31 Torrid Cores or snap on cores from Palomar Engineering at:
https://palomar-engineers.com/ferrite-products/

Also maybe a call to the inverter manufacture may help. Be advised the manufactures of these units do NOT have to meet any FCC spec for RFI as there is no rules for these mobile type units so the manufactures may blow you off, or ask you call the FCC or call the incoming paper clips dept.

As said before it always best to filter the RFI at the source, as the RFI can not be filtered in a antenna coax as the RFI is at the same frequency and the CB Frequencies. Alternator wine RFI some times can be filtered out with a in line coax filter, have done it many times on the older CB radios. A inline parelall LC circuit using a 88mH Choke and a .1uF cap in a metal box worked for me.

Good luck please let us know your trouble shooting method and madness, and the fix.

Jay in the Great Mojave Desert.... "Next Gas 150 Miles"