View Full Version : Noise on HF
petrus
02-22-2009, 06:25 AM
So what kind of things has everyone done to abate noise? I have S9 ignition noise on my IC7000 in my 2008 Unlimited. 40m is the worst band. AM is pretty much useless with the engine running. I've bonded the exhaust to the frame in 3 places with braided ground strap, and that might have helped a little, but probably wasn't worth the effort. Anyone have luck with ferrite beads on the ignition wires? Anything else you've tried?
Thanks and 73,
pete AA8L
I installed a Ferrite on the power lead to the radio that helped make 40m better. Hve not tried ignition.
N4XGI
AK4Dave
02-22-2009, 11:40 AM
I have not installed an HF rig in my JK yet, and by the sounds of it, it's not something I'm looking forward to. I remember the fuel pump on an old Dakota I had made so much noise it was unbearable.
As you probably already know you need to determine if the noise is being picked up by the antenna, or is coming through the powerline, or God forbid.....BOTH:eek2: No fun at all.:sad2: If you determine it is on the powerline, as already mentioned, ferrite beads can work wonders. They are cheap, and it's not a bad idea to start throwing them on everywhere you think could be suspect. I remember you can also buy an actual 12v automotive noise "choke" to run on your radio's powerline. I think I bought one years ago at Rat Shack. I may still have it so I'll look for it and let you know.
With all the plastic in vehicles nowadays, it's never a bad idea to start adding grounding straps all over the vehicle. From everything I've gathered over the years, you can never have enough. Sometimes even moving the ground to a different location may help.
If you find the antenna is picking up rf noise from the Jeep, then good luck.:dontknow2: I've even known some HAMS to actually build a grounded metal box around the noise generator and get some results. Or wrap a few grounding straps around it which is essentially "almost" doing the same thing.
Sorry, but at this time, without having an HF rig in my Jeep myself and not being exposed to the noise, this is about the most I can say on the subject. I know it can drive a guy crazy, but stick with it. All it takes sometimes is one extra ferrite bead, or that one ground strap placed in the right place, and problem solved.
Oh, I just remembered a good source for beads and rf shield "kits", Check them out. https://www.amidoncorp.com/
73 & Good Luck...
Dave / wl7cmg
PS.....Do the Icom mobiles have noise blankers? If so, I take it they won't take out the noise? Probably not, as even some of the best base station noise blankers won't take out all noise sources. 73
petrus
02-22-2009, 03:41 PM
Jeff: ferrite on the power lead sounds promising, thanks!
Dave: Yeah, the noise blanker on the IC7000 is actually pretty good, just need to do better. To be more specific, I should have said "S9 without the noise blanker, at highway speed" in the original post.
pete AA8L
motrac45
02-22-2009, 04:16 PM
Well I not a ham, but I have worked for Motorola for 30 years. I measured my 07 4 door with a fluke meter it was bouncing between 20-30 mv AC. If you have a fluke meter or an AC scope you should measure about the same. If you measure about 150 or more mv AC, then you need to buy a motor noise suppression kit, which is a large capasitor, that will filter, reduce, the AC componet from your charging system.
N2MWL
02-24-2009, 03:12 PM
Did you ever determine whether the antenna was picking up your noise or the power lines.....I hesitate to put an HF rig in the Unlimited myself.....
73
Mike
N2MWL
Tracking noise down
determine if the noise is conducted or radiated.
Conducted noise will get into the radio via the wiring. Here is how to check.
1.Take antenna off of radio.
2. Turn all accessories off.
3. start engine and turn on radio. Select AM mode, Noise Blanker off.
4. Any noise? Turn AC on and off. Now you know.
5. Turn engine off. Now turn accessories on and off one at a time and listen for noise. Now you know which ones conduct.
You can try Amidon Ferrites Mix 31 ( for 0-50MHZ)on the leads of the noise sources you have found. Or try shielding the leads.
Radiated noise gets in via the antenna. Here is how to check.
1. Put antenna back on radio.
2. Turn on Radio, AM mode, Noise Blanker off.
3. Make a note of the noise level.
4. Start the engine.
5. Poping noise that varies with RPM? ignition wires. I have some of this. I am thinking of buying some braid and slipping over each wire
6. Wining noise that varies with RPM? Alternator.
7. Try all of the accessories one at a time again. Make a note of which ones radiate. One noise may mask another. Work on one at a time.
The radiated noise I am trying to solve on my JK happens as I am engaging the clutch. Once it is engaged the noise is gone.
N2MWL
03-05-2009, 06:55 AM
Just bumping this to the top in case someone might have some new info..... :)
No new info. However I did write Jeep a letter and asked for technical assistance on solving the noise issues. I did this a few years back with a GMC truck and GM sent me a manual they used to install Communications radios for Federal Park agents, and one of the Engineers contacted me. They were very helpful. We tracked the noise down to the computer. I put a flat ferrite on the ribbon cable and fixed it.
We will see what Jeep comes up with.
N4XGI
AK4Dave
03-05-2009, 07:58 PM
Just bumping this to the top in case someone might have some new info..... :)
As Jeff has shown....FERRITES ARE YOUR FRIENDS...!!!! Have you checked with Amidon yet about their kits? They are a real good source. I also still think you can buy wrap around ferrites still from Rat Shack.
zoomzoomjr
03-05-2009, 08:53 PM
As Jeff has shown....FERRITES ARE YOUR FRIENDS...!!!! Have you checked with Amidon yet about their kits? They are a real good source. I also still think you can buy wrap around ferrites still from Rat Shack.
I use Jameco.com for small parts that are usually harder to find. Look at part #'s 218174 and 217842.
N2MWL
03-06-2009, 06:22 AM
As Jeff has shown....FERRITES ARE YOUR FRIENDS...!!!! Have you checked with Amidon yet about their kits? They are a real good source. I also still think you can buy wrap around ferrites still from Rat Shack.
I'll look into Amidon, I did check Rat Shack and the kid had that I have no idea what your talking about look when I asked !! LOL
73
Mike
N2MWL
AK4Dave
03-06-2009, 07:37 PM
I'll look into Amidon, I did check Rat Shack and the kid had that I have no idea what your talking about look when I asked !! LOL
73
Mike
N2MWL
Yes.....I've seen that look...:rotflmao2: I found them by accident there a long time ago. They may not even stock them anymore. They are the type that are like a rectangle or square doughnut. They have plastic clips holding them together, and when you unclip them the farrites come apart so you can wrap your wires around them. Then you just put them back together and snap the clips. Pretty handy actually.
N2MWL
03-08-2009, 09:00 AM
Yes.....I've seen that look...:rotflmao2: I found them by accident there a long time ago. They may not even stock them anymore. They are the type that are like a rectangle or square doughnut. They have plastic clips holding them together, and when you unclip them the farrites come apart so you can wrap your wires around them. Then you just put them back together and snap the clips. Pretty handy actually.
Ok, I'll check into it some more when I get back in town.....On an unrelated note I might be buying an Icom 7K off my buddy Scott, we are trying to work out the details now.... :crazyeyes: :crazyeyes:
AK4Dave
03-08-2009, 01:24 PM
Ok, I'll check into it some more when I get back in town.....On an unrelated note I might be buying an Icom 7K off my buddy Scott, we are trying to work out the details now.... :crazyeyes: :crazyeyes:
Another EXCELLENT radio....!!! :thumbsup:
Good luck with that...
No new info. However I did write Jeep a letter and asked for technical assistance on solving the noise issues. I did this a few years back with a GMC truck and GM sent me a manual they used to install Communications radios for Federal Park agents, and one of the Engineers contacted me. They were very helpful. We tracked the noise down to the computer. I put a flat ferrite on the ribbon cable and fixed it.
We will see what Jeep comes up with.
N4XGI
Well I heard back frpm Jeep. Very nice guy named John called me. I could tell he had read my letter and done some research. But not much help. He suggested I go to a radio shop that installs radios for police, etc.
So I have been looking for a improved set of plug wires. May have to make a set.
I wanted to remind everyone that not all ferrites are created equal.
Amidon Ferrites Mix 31 work for HF. They make snap on beads that are easy to install. You can also get them from DX engineering.
N4XGI
AK4Dave
03-08-2009, 06:43 PM
Well I heard back frpm Jeep. Very nice guy named John called me. I could tell he had read my letter and done some research. But not much help. He suggested I go to a radio shop that installs radios for police, etc.
So I have been looking for a improved set of plug wires. May have to make a set.
I wanted to remind everyone that not all ferrites are created equal.
Amidon Ferrites Mix 31 work for HF. They make snap on beads that are easy to install. You can also get them from DX engineering.
N4XGI
Well that's a drag that the Jeep guy wan't much help. I forgot about resister type plug wires....that might help for sure.
Yes, very true about the ferrites and thanks for bringing that up...I'd forgotten about that too:dontknow2:
N2MWL
03-08-2009, 06:49 PM
Another EXCELLENT radio....!!! :thumbsup:
Good luck with that...
Thanks, were working on it !!
AK4Dave
03-10-2009, 07:32 PM
Jeff: ferrite on the power lead sounds promising, thanks!
Dave: Yeah, the noise blanker on the IC7000 is actually pretty good, just need to do better. To be more specific, I should have said "S9 without the noise blanker, at highway speed" in the original post.
pete AA8L
Any luck yet Pete?
N2MWL
03-11-2009, 04:39 AM
The deal on the 7k fell thru, but I am high bidder on a 756Pro for the house...I'm going to give Tarheel a call when I get home later today and see what they say about Jeep noise..Looks like a Tarheel will be my antenna of choice for the JK..
AK4Dave
03-11-2009, 08:13 PM
The deal on the 7k fell thru, but I am high bidder on a 756Pro for the house...I'm going to give Tarheel a call when I get home later today and see what they say about Jeep noise..Looks like a Tarheel will be my antenna of choice for the JK..
Too bad about the 7k. I had a Pro for awhile in the shack while I was taking my "radio journey" as i call it. They are good rigs, and pretty popular for sure. I'm just not that into "eye candy", altho the scope is nice, I just wasn't that into it. But I think the main reason is I like bigger radios for the shack. The Pro is pretty small as a base, which makes all the knobs and stuff even smaller. It's just a matter of preference tho.
Good luck....
N2MWL
03-12-2009, 01:06 PM
Too bad about the 7k. I had a Pro for awhile in the shack while I was taking my "radio journey" as i call it. They are good rigs, and pretty popular for sure. I'm just not that into "eye candy", altho the scope is nice, I just wasn't that into it. But I think the main reason is I like bigger radios for the shack. The Pro is pretty small as a base, which makes all the knobs and stuff even smaller. It's just a matter of preference tho.
Good luck....
Got out bid...... :mad:
petrus
04-28-2009, 06:12 PM
Any luck yet Pete?
Well today I received 10 Mix 31 split beads from DX Engineering, .525" I.D. I put one on each of the three short ignition wires (the driver's side ones), and one at each end of the long wires (the passenger side ones). So I used 9 beads. This suppressed the ignition noise about 2 S-units on 40 meters. So maybe S-7 rather than S-9. So there you go. Worth the $50? Nope. Fun to experiment with this stuff, though.
Pete AA8L
N2MWL
04-29-2009, 04:34 AM
Well today I received 10 Mix 31 split beads from DX Engineering, .525" I.D. I put one on each of the three short ignition wires (the driver's side ones), and one at each end of the long wires (the passenger side ones). So I used 9 beads. This suppressed the ignition noise about 2 S-units on 40 meters. So maybe S-7 rather than S-9. So there you go. Worth the $50? Nope. Fun to experiment with this stuff, though.
Pete AA8L
Sorry you didn't get better results, we appreciate your input !! :)
AK4Dave
04-29-2009, 07:21 PM
Well today I received 10 Mix 31 split beads from DX Engineering, .525" I.D. I put one on each of the three short ignition wires (the driver's side ones), and one at each end of the long wires (the passenger side ones). So I used 9 beads. This suppressed the ignition noise about 2 S-units on 40 meters. So maybe S-7 rather than S-9. So there you go. Worth the $50? Nope. Fun to experiment with this stuff, though.
Pete AA8L
Well that's a drag. You might want to call Amidon and see what they say. Tell them what you have now and see if they have any suggestions. This is pretty much all these people deal with.
Good Luck....
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