Omega Owners Forum

Omega Help Area => Omega Electrical and Audio Help => Topic started by: Thatcher on 13 August 2010, 16:41:27

Title: Interference on portable tranceivers
Post by: Thatcher on 13 August 2010, 16:41:27
Interference is caused on 2 different tranceivers, when engine is running and when not.
Particularly bad on 144.5 mhz which is unuseable
Anyone any advice please?
2003 Omega auto
Title: Re: Interference on portable tranceivers
Post by: Kevin Wood on 13 August 2010, 16:43:47
Not noticed it myself but will check. I take it it's from something in the car? Does the key have to be in the accessory position, or the run position?

Kevin
Title: Re: Interference on portable tranceivers
Post by: Sixstring on 13 August 2010, 17:55:55
Don't get any interference on my 2m Yeasu, is it at any particular speed?
Title: Re: Interference on portable tranceivers
Post by: Omegafantasy on 13 August 2010, 18:03:32
I have no issues with noise on the 2 meter band in my Omega, but as it's a 95 I don't have that much electronics in it.

However, I do get a small range of noise when my stereo is on (Alpine head unit).

Does it happen all the time, or in certain situations? If it's there all the time I would think alarm system, info display (of any kind) or immobilizer transponder (although I think it's on 433'ish MHz).

Anyway, I reckon you're a ham then?  ;D
Title: Re: Interference on portable tranceivers
Post by: Kevin Wood on 13 August 2010, 22:41:59
Quote
Anyway, I reckon you're a ham then?  ;D

Oh, no. Looks like there's several of us. ;)

Kevin
Title: Re: Interference on portable tranceivers
Post by: Omegafantasy on 13 August 2010, 22:47:44
Hehe, yeah :)
Better set up some kind of OOF sked then? 80m is fine to UK usually.
Title: Re: Interference on portable tranceivers
Post by: Kevin Wood on 13 August 2010, 23:23:15
Quote
Hehe, yeah :)
Better set up some kind of OOF sked then? 80m is fine to UK usually.

Ahh, not a bad idea, actually. And a reminder to sort out my antenna system. ::)

Can't remember if it's the antenna or house wiring that's resonant on 80m at the moment. ;D

Kevin
Title: Re: Interference on portable tranceivers
Post by: Sixstring on 14 August 2010, 17:35:22
G1 or G8????

(that'll make a few people wonder what we are on about!!)
Title: Re: Interference on portable tranceivers
Post by: Kevin Wood on 15 August 2010, 01:36:11
G7 in my case. ::)
Title: Re: Interference on portable tranceivers
Post by: Omegafantasy on 15 August 2010, 02:20:23
Not a G at all here, I am an LA :)
Title: Re: Interference on portable tranceivers
Post by: Ken T on 15 August 2010, 09:00:59
I'm an M1.

The rig hasn't been on for a while, so much else to do.

Ken
Title: Re: Interference on portable tranceivers
Post by: TheBoy on 15 August 2010, 10:00:14
Quote
G7 in my case. ::)
Old git :P
Title: Re: Interference on portable tranceivers
Post by: zirk on 15 August 2010, 13:58:22
Quote
Quote
G7 in my case. ::)
Old git :P

Think that makes me an older git then, G8P**, although not used it for a long while, guess that's what happens when you choose a career in Radio and Telecoms for the last 25 years.  ;)
Title: Re: Interference on portable tranceivers
Post by: steve_daly on 15 August 2010, 18:11:25
Quote
G1 or G8????

(that'll make a few people wonder what we are on about!!)


Call signs :P
Title: Re: Interference on portable tranceivers
Post by: Radiomarko on 19 August 2010, 17:13:51
G7xxx

144.5 iirc is prone to processor harmonic noise, particularly bad with old, old slow ones - so that may indeed suggest some damn chip that runs a display, gps, mobile phone unit, alarm unit, ecu etc -

To search you could try taking the antenna off the handy, seeing if it can still hear the noise and using it to try to pinpoint the source around the car?
Title: Re: Interference on portable tranceivers
Post by: Kevin Wood on 19 August 2010, 23:20:04
Quote
Quote
Quote
G7 in my case. ::)
Old git :P

Think that makes me an older git then, G8P**, although not used it for a long while, guess that's what happens when you choose a career in Radio and Telecoms for the last 25 years.  ;)

I know what you mean.

I tend to get it out of my system in a couple of concentrated bouts each year.. VHF/UHF NFD being my favourite. Operated with G0FBB/P for the last couple of years (came 2nd last year, IIRC) 8-). They have lots of toys to play with:

 :D

Kevin

(http://images.omegaowners.com/images/kevin/IMGP4668.JPG)
(http://images.omegaowners.com/images/kevin/IMGP4711.JPG)
Title: Re: Interference on portable tranceivers
Post by: Radiomarko on 21 August 2010, 17:06:21
Nice field day pics, nothing like the sight of the sun glinting on expensive metal   ;D  I was in the team that came first in UKSMG World Six Metre Contest in the early 90's - great fun, ended up completely hoarse after 24 hours....

I cannot boast much metal in the sky at home, but I am a member of a club that can boast about its antenna set up. I operate from there several times a year, so if you hear a strangely english accent calling CQ from RM3M on 20 with an ear shattering signal -  give me a shout!

http://translate.googleusercontent.com/translate_c?hl=en&sl=auto&tl=en&u=http://rk3mwd.ystu.ru/na%2520kryshe.htm&rurl=translate.google.com&usg=ALkJrhhT2qs2H_sxGfdaorV5mwwCVqBY9g
Title: Re: Interference on portable tranceivers
Post by: Thatcher on 18 June 2011, 15:47:44
Still no advice on this. Noise sounds like a helicopter (SWAT), and is present when engine is switched off as well as on.
Tried vx-8, e90, 817, 987.None connected to the car power.
Tried various antennas.

Any  clues? >:(
Lowely 2e0
Title: Re: Interference on portable tranceivers
Post by: Kevin Wood on 18 June 2011, 19:29:51
OK. time to start narrowing things down then.

Is the noise there regardless of whether the radio is powered from the car or its' own internal batteries?

Is it there on a handheld radio with its' own antenna or just an antenna mounted on the vehicle?

If so, can you narrow it down by checking around the car with a handheld to see where it's strongest?

Can you power down circuits on the vehicle until the noise stops? First try it with the ignition key removed. If the noise is still there try pulling fuses until you find the offending circuit. Beware that you'll need a valid code for the head unit if you remove power from it.

Let us know what you find and we'll take it from there.

Kevin
Title: Re: Interference on portable tranceivers
Post by: I_want_an_Omega on 19 June 2011, 22:14:51
Quote
Quote
Quote
G7 in my case. ::)
Old git :P

Think that makes me an older git then, G8P**, although not used it for a long while, guess that's what happens when you choose a career in Radio and Telecoms for the last 25 years.  ;)

Makes me an even older git then G8O** - stopped for same reasons + discovered females @ the same time my chums were playing with their Westmisters  ::)