HF (Ham) noise

[nutty Lurker Find all posts View Profile Close nutty]

Hi Folks

This might be a long shot....

Have just installed a TS480HX radio into a new diesel Prado and have S9 noise levels, non QRN, Static not pulsing noise.

Have any hams out there had similar experiences??

The noise comes in as soon as the ignition is turned on at about an S6 level then once the engine is started I have S9 noise.

Am planning to earth strap the bonnet, doors and antenna (have good electrical ground as per ohm meter on the antenna) however I thought a post here could save me a hell of a lot of work if there is a known problem/fix.

Thanks in advance

Ian VK6FIJG

[Strahan Advanced Member Find all posts View Profile Close Strahan]

Yikes!
As soon as the ign is on?
Got to ask all the obvious questions first:
Is the radio earthed ok?
Can you try it in another vehicle to see if its the same?

There are few of us nerds about here. I have had my IC7000 in the car with no problem at all and mine is a petrol.

Hope we can get to the bottom it.

VK7CBR (formally VK6PAC :wink: )

[nutty Lurker Find all posts View Profile Close nutty]

Thanks Strahan

Yes it is very well earthed and no I have not tried it in another vehicle.

Don't want to complicate things further...... But ..... I have the HX model and have a featuretech ATU installed as well (this is grounded well though). I am running a Terlin outreach antenna.

Something I have noticed with the vehicle is that I am very susceptible to static charges when getting out, both prior to fitment and after, I will get a zap when grabbing the door frame etc.

Just wondering if that might be adding to the noise???

73 and thanks for the reply.

[speedcomm Senior Member Find all posts View Profile Close speedcomm]

Gday Nutty !
Why are you running an ATU with the Terlin ? I guess maybe on 80m it would allow you to keep your VSWR down right accross the 80m band ? Sounds to me like earthing, I had all sorts of issues with my Terlin on my Yaesu 857D till I put a heavy earth strap direct from the base of the Terlin mount back to the neg batt terminal, they say in the instructions for the antennas earthing is everything, I have heard of people having dramas with the later model LC100 series diesels from memory the injectors ? but yours is not engine related as it happens when you turn on the ignition. I have been using the braid off a piece of RG213 as my earth straps, works well. I would start with the antenna and the tranciever earths and work out from there, doing body panels etc as you mention. Oh and as a side experiment, take the ATU right out of the loop see if that has any impact. Keep us posted. You will get rid of it eventually !
Tim VK2HLT

[glipschitz Junior Member Find all posts View Profile Close glipschitz]

Ahh welcome to the world of diesel fuel pump noise!

Where is your antenna mounted? Get it as far away from your engine as possible.

The Nissan Patrol used to have birdies on 146.550MHz or there abouts, and the Pajero used to have birdies on 2m, 70cm and 6m as well as throwing all sorts of crap like S9 noise.

Good Earthing, a DSP speaker and making sure your car isn't noisy with other radios is a good starting point.

Check your coax runs and try and keep them away from other car electronics and also as far away from the engine as possible.

Any questions, just ask.

Greg (aka The FunkyMan) de VK3FUNK

[nutty Lurker Find all posts View Profile Close nutty]

Thanks guys

The reason for the atu is I'm too slack to get out and change bands, it also gives me the ability to tune wire if needed when stationary/camped etc.

Will be able to get stuck into this next week and will feed back the results.

Antenna is bullbar mounted.

will start with grounding and such.

73 guy's

Ian

[nutty Lurker Find all posts View Profile Close nutty]

By the way

I have an alinco 2m and 70cm rig that has the coax run along the same route as the HF and is dead quite???...... spot on.

[Strahan Advanced Member Find all posts View Profile Close Strahan]

Make sure that the bullbar is really well grounded, sounds like it might be the culprit.

Maybe look to moving the antenna to the rear of the vehicle as well. i have a mount behind the spare wheel carrier that fits really well.

Good luck this weekend.

[glipschitz Junior Member Find all posts View Profile Close glipschitz]

UHF/VHF's main interference is usually things like alternator whine and the likes, where as HF will pickup anything and everything.

I was a bit miffed as to why you were using the ATU with the Terlin too. The Terlin by itself is fantastic.

The other thing to check is your VSWR with and without the ATU and see how it is performing.

Cheers,

Funky.

[nutty Lurker Find all posts View Profile Close nutty]

Well here's the feedback.....

I disconnected the ATU and lo and behold a noiseless (virtually) signal.
Yep the idea was to tune the 80m band, however I think that the ATU was causing the coax to act as a radiator and was picking absoblutely everything up.

Did a little more grounding and more to do as the exhaust might be a good culprit.

Here is a great website that I think should help anyone (like me) in the future.... http://www.k0bg.com/

A very good site.

You live and learn....

The ATU can stay in the vehicle for long wire use portable I guess.

Thanks Guy's

Ian VK6FIJG

[Strahan Advanced Member Find all posts View Profile Close Strahan]

Good to see its sorted.
Put up a skyhook for my dipole today .

That website is a good one isn't it? Lots of really good info for mobile stations.

[nutty Lurker Find all posts View Profile Close nutty]

Yep it certainly is Strahan.

And I hope having the link now on Prado Point might help others with fitouts of HF as it isn't a simple undertaking.

73
Ian