Lots of electrical noise in new set up

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A7HG
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Lots of electrical noise in new set up

#396801

Post by A7HG »

I have just set up a new connex 4600 turbo that’s been converted to 11 meter by a well know YouTube guy from TX in a 2018 kenworth T880. this being said the radio is wired straight to the batts, the case is grounded to a green bolt on the chassis with other grounds, the Wilson trucker 2000 is new with new Stainless mount and stud, the mount is well grounded to the truck body and I have ferrite cores on all the wires and cables. My SWR is 1.2 all the way across the 40 CB channels. All of this and I still get electrical noise when the HVAC fan is on and the noise varies with the fan speed, I get a loud electrical squeal when the tarp motor is activated to roll my tarp, I get static when the turn signals, headlight or wipers are on. This is killing me because I have the same exact setup in my older 1987 359 Peterbilt and I have no electrical interference at all, even with the squelch turned all the way down. Any advice or opinions are welcomed cause I’m all out of ideas. Thanks in advance....
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MDYoungblood
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#396805

Post by MDYoungblood »

Try removing the case ground from the location everything else is grounded to, see if that reduces the noise, place it somewhere all on it's own close to the radio, the radio's negative wire can go the same place. All the power leads need to be as short as possible so as to not pick up any noise. Now to figure out if the noises are being picked up by the power leads or the antenna and coax. With the radio on, engine off, unplug the antenna (don't key the mic), turn on one of the offending noise makers at a time, then start the engine to see what noises may be heard. If the noise isn't present than it is being picked up by the antenna system.

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"321, West Manchester Township, PA"

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A7HG
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#396835

Post by A7HG »

I bought and installed a “blackBox” Noise eliminator in line and it completely cleared it up. These things are used in rescue and ambulances to cut out all electrical noise from the special equipment, monitors and emergency radios. They’re rated for 16 volts and 150 amps so it’s more than enough for what I needed. Best $50 investment I’ve made in a while.
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#396839

Post by MDYoungblood »

Glad you got it handled,, if you wouldn't mind post the name or brand of "black box" you used so others with this same problem can try it out.

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Greg
"321, West Manchester Township, PA"

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A7HG
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#396852

Post by A7HG »

It’s made by CWS. [Please login or register to view this link]. I got mine from eBay. Here is the link. If this is prohibited by forum rules just delete it, but I didn’t know any other way to show you guys the product. [Please login or register to view this link]
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sonoma
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#396854

Post by sonoma »

thanks for posting the black box. helps a lot knowing what you used.
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51

#396861

Post by 51 »

you should still get rid of that chassis ground on your radio and amp if you have one. they do nothing except introduce the possibility of creating ground loops. let the dc ground (which is connected to the chassis) and the coax shield take care of the chassis rf grounding. might be where your whole receiver noise problem started. ground loops = receiver noise, rf on your signal, rf hot spots etc.. not a good thing
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A7HG
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#396881

Post by A7HG »

Yes, I did remove the radio chassis ground. When I did this the electric noise from the HVAC fan actually got worse. I also tried the graphite powder in the hubs from the above sticky thread. Between the blackBox and the graphite I can ride with my squelch turned all the way back and I only get a small amount of hiss.
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443 Arizona
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#401690

Post by 443 Arizona »

i saw on CBTricks, a fix for the power input static, it consisted of putting a capacitor across the pos. and neg. at the radio input. Cap size of 16 to 25 volt with a 2500 to 4700 mcf rating. connect pos. to pos. and neg. to neg.
i am going to be doing this on one of my radio's soon so i will report back
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Gunner357
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#402775

Post by Gunner357 »

443 Arizona wrote: March 31st, 2020, 11:53 pm i saw on CBTricks, a fix for the power input static, it consisted of putting a capacitor across the pos. and neg. at the radio input. Cap size of 16 to 25 volt with a 2500 to 4700 mcf rating. connect pos. to pos. and neg. to neg.
i am going to be doing this on one of my radio's soon so i will report back
I did this on my 04 Ram with a Galaxy and a amp it works
Yaesu FT920 (KE8PSI)
Galaxy88hl
Galaxy 99v
Cobra148 GTL w/ channel expansion
Cobra 29ltd Chrome
Magnaforce 350
Predator 10k
V58 Maco
Homemade Dipole base antenna
EFHW-8010 Multi-band End Fed Half Wave Antenna
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cecil
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#402786

Post by cecil »

Thanks for the info on the black box. Got rf issues too.
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