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  1. FT-857
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2m QRM

 

Dear all,

I have QRM 5/9+. Whether the antenna is on the roof of the car. Same with the Atas 120A.
My tests :
I disconnected the antenna. Car engine shut off. S4 to 5 of QRM. Engine on, S7. With antenna?: S8 to 9+?
I took my portable, I went around the car, outside and inside. QRM: 0

The concern therefore comes from the Yaesu 857D. I looked in the manual. I didn't find?a?solution. I reset the Yaesu. Nopes.

I hope someone will have a solution for me.

Thanks in advance. Best regards.


Vy 73's
Xavier Amand -?ON4XA
?
??
Secretary of ON6SD belgian Sugar Delta Ham radio club
?

UBA-UFRC-EURAO member

Rue de Bouillon 250
B-5574 Beauraing - Pondr?me
Belgium

Tel: +32 496 32 22 22
Fax : +32 82 22 78 69
 

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Hello Xavier,

For clarification it is not QRM…..QRM is interference from adjacent ham stations or other RF signals. You have man made noise RFI, from your vehicle. This can sometimes be very difficult to eliminate. Usual related to poor grounds on the vehicle. First make sure your antenna mount is well grounded to vehicle. If you are using magnetic mount that is the problem.?

Next is where it can get very frustrating. you need to make sure all doors, hatch, car hood are well bonded to car frame.

This is a good primer on the subject of RFI

RFI youtube?

Good Luck
Jack
W4GRJ

><))):>

On Oct 10, 2022, at 5:51 AM, Xavier Amand <on4xa.xavier@...> wrote:

?
Dear all,

I have QRM 5/9+. Whether the antenna is on the roof of the car. Same with the Atas 120A.
My tests :
I disconnected the antenna. Car engine shut off. S4 to 5 of QRM. Engine on, S7. With antenna?: S8 to 9+?
I took my portable, I went around the car, outside and inside. QRM: 0

The concern therefore comes from the Yaesu 857D. I looked in the manual. I didn't find?a?solution. I reset the Yaesu. Nopes.

I hope someone will have a solution for me.

Thanks in advance. Best regards.


Vy 73's
Xavier Amand -?ON4XA
?
??
Secretary of ON6SD belgian Sugar Delta Ham radio club
?

UBA-UFRC-EURAO member

Rue de Bouillon 250
B-5574 Beauraing - Pondr?me
Belgium

Tel: +32 496 32 22 22
Fax : +32 82 22 78 69
 

开云体育


Hi Xavier,

perhaps, this is the reason.
Look there:


73
Alfred- DJ0GM

Xavier Amand schrieb am 10.10.2022 um 11:51:

Dear all,

I have QRM 5/9+. Whether the antenna is on the roof of the car. Same with the Atas 120A.
My tests :
I disconnected the antenna. Car engine shut off. S4 to 5 of QRM. Engine on, S7. With antenna?: S8 to 9+?
I took my portable, I went around the car, outside and inside. QRM: 0

The concern therefore comes from the Yaesu 857D. I looked in the manual. I didn't find?a?solution. I reset the Yaesu. Nopes.

I hope someone will have a solution for me.

Thanks in advance. Best regards.
Vy 73's
Xavier Amand -?ON4XA
?
??
Secretary of ON6SD belgian Sugar Delta Ham radio club
?

UBA-UFRC-EURAO member

Rue de Bouillon 250
B-5574 Beauraing - Pondr?me
Belgium

Tel: +32 496 32 22 22
Fax : +32 82 22 78 69
_._,_._,_
 

What car??
New cars have so many electronics built in that they can be a problem.
I have a friend with a 2007 Jeep Wrangler that horrendous noise on 2 meters and he had a bad antenna cable on his new magnetic antenna.?
Are you pulling power directly from the battery?
Do you have any ferrite choles on the power line?
Do you have any over the VHF/UHF feed line?

The fix for my friend was to install a diamond antenna on the bike rack? at the rear of the car with a good coax feedline. The rear location was far enough away from the electrical hash to work. He mounted the radio in the rear and a cable to the front panel on the dash. That radio was a TM-D710GE.?
 

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Agree with Alfred,
Bad Ceramic filter can cause this problem, S meter should be close to zero with no antenna.
It also sounds like you have an antenna ground issue.
Jack
W4GRJ

On Oct 10, 2022, at 7:12 AM, DL0PAF <dl0paf@...> wrote:

?

Hi Xavier,

perhaps, this is the reason.
Look there:


73
Alfred- DJ0GM

Xavier Amand schrieb am 10.10.2022 um 11:51:
Dear all,

I have QRM 5/9+. Whether the antenna is on the roof of the car. Same with the Atas 120A.
My tests :
I disconnected the antenna. Car engine shut off. S4 to 5 of QRM. Engine on, S7. With antenna?: S8 to 9+?
I took my portable, I went around the car, outside and inside. QRM: 0

The concern therefore comes from the Yaesu 857D. I looked in the manual. I didn't find?a?solution. I reset the Yaesu. Nopes.

I hope someone will have a solution for me.

Thanks in advance. Best regards.
Vy 73's
Xavier Amand -?ON4XA
?
??
Secretary of ON6SD belgian Sugar Delta Ham radio club
?

UBA-UFRC-EURAO member

Rue de Bouillon 250
B-5574 Beauraing - Pondr?me
Belgium

Tel: +32 496 32 22 22
Fax : +32 82 22 78 69
 

Bad ceramic filters should be apparent on all bands in the same mode as 2 meters as that part of the IF is common to VHF/UHF and HF.?
It would also be apparent if the radio is operated from the home QTH away from the car.
It is possible to be a cause of the noise, but is less prevalent in radios with the new style ceramic filters.
 

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Does it change at all with the attenuator swirched in?? I don't remember if the preamp (IPO) can be switched off on 2M.? But I would try toggling that.? If I had to guess, I would say that the preamp (or some other stage unique to 2M) is oscillating.? Probably need to send it in for repair.? I have used HamRadioRepair.com quite successfully in the past.?



Ron Jakubowski, K2RJ?

Tab? S5e
 

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I've used the Diamond K-400S mount on my last several cars (Cadillacs, Mercedes, Lincoln Continental), all with voluminous electronics, and have had no interference to an FT-857D on either HF or V/UHF.? The antenna is a Diamond dual-band 5/8th wave mounted on the rear deck lid.? Coax is whatever was supplied with the mount (13.6 feet), long enough to reach the driver's seat.? The transceiver lays on the floor underneath the driver's seat with the control-head clipped to an air-conditioner outlet using a PRO-CLIP mount.? No Screws, no adhesives, no restricted air flow, no ferrites.

73,
Kent
K9ZTV



Virus-free.
Don Goodhart
 

Hello Everyone;
? ? ?I too am using the Diamond 400S on a 2008 Hummer H3. I was having trouble with the HSWR until I installed Grounding Braid to all Doors, rear Hatch/door, front hood. The main issue was ground.? My SWR NOW 1.1, With less than a 1/8th of a Watt reflection. I am currently using a YAESU FT-857 WITH ATAS-120A AS ANTENNA.? AND NOW TUNES from 440 to 7.175 mhz (All Area of the ATAS-120A turning)
--
Thank You
Don Goodhart
N6eur0u8@...
 

A good place for technical info on setting up for mobile is:
http://www.k0bg.com/
--
Compton
VK2HRX
Sydney, Australia

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