[TowerTalk] noise

Tue, 26 Aug 1997 10:34:16 -0400

Hi Roger

Many thanks for the ideas (I've had several emailed to me directly)

More on this:

I've looked at night, no visiable arcing
The radio is grounded to the frame at the radio (IC-706)
The DC power lead is NOT shielded
The noise can be heard by another ham parked near me (at the moment, this
precludes the power lead idea)
When travelling under a bridge and listening to a AM station, the ignition
noise can be heard
(I haven't done the AM radio sniffing yet, but the signal is so loud it
might be difficult to attenuate)

Options so far (and I have thought of all these):

Turn the car off when talking (makes for long trips)
Sell the car (not to a ham)  
Forget HF mobiling (not an option)
Take up spark gap mobile

The funny thing is this only happens to 1988 Honda Civics (the only Honda
with the Black Bumper).  If I am in the other car with HF and drive near
another 1988 Honda Civic DX, the ignition noise is heard.  

Many thanks so far....mike

73

At 10:12 AM 8/26/97 -0400, you wrote:
>Hi Dick,
>
>re ignition noise and finding shielded distributor caps etc....
>
>My best guess is to look in a J.C. Whitney  automotive parts catalog.
>Perhaps they even have a web site. I haven't looked in one of those
>automotive catalogs since I was a kid foolin' with hot rods. Any big
>newsstand or Barns and Noble Bookstores should have them. 
>
>I would also imagine that in a real pinch you could fashion something
>out of aluminum foil.... say the real heavy duty stuff used for
>baking.... and double or triple layer it.  
>
>If you can put your hand on the distributor cap or any of the ignition
>wiring and get a nice HV jolt.... you probably have an insulation
>breakdown problem.  Since the spark is arcing where it shouldn't- THAT
>is what's causing the majority of your ignition noise! Ignition noise
>from high voltage arcing is typically heard on your radio's receiver to
>change in frequency as you vary the engine speed.
>
>Another trick we use to locate the source of the sparking - is to park
>the car in the garage at night and run the engine - with the garage
>doors open - of course - and all the lights off. When your eyes have
>become dark adapted... lean into the engine compartment and look for
>the blue sparks of ignition arcing and listen for the characteristic
>loud snapping sound... which to the trained ear is different than the
>sound of noisy valve lifters.  
>
>It's also a good idea when doing this to not wear loose clothing like
>ties and bolo's.  You wouldn't want to get wrapped up in an engine belt
>in the dark... would you?  (THIS... is a wonderful seed of an idea for
>one of K4IBP, Jack Goforth's humorous stories. I'd do one myself....
>but I promised I wouldn't!)
>
>Hope some of this has been of help.
>
>Roger, K2JAS.... "Jealous About Sparking"
>
>內躬偕爻,虜,齯滌`偕爻內躬偕爻,虜,齯滌`偕爻齯滌`偕爻,虜,齯滌`偕爻內躬偕爻
>
>At 04:21 AM 8/26/97 +0000, you wrote:
>>>If you have noisy ignition cabling.... there are shielded ignition
>>>wiring kits.  If you have a noisy distributor cap.... there are
>>>shielded caps you can buy.
>>
>>Shielded distributor caps?!  Ooooh, I would love to find one of those!
>>Where would I look?
>>
>>73, Dick
>>
>>--
>>Dick Flanagan W6OLD CFII Minden, Nevada
>>Visit http://www.delphi.com/electronic/
>
>
>--
>FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
>Submissions:         	
>Administrative requests:  towertalk-REQUEST@contesting.com
>Problems:                 owner-towertalk@contesting.com
>Search:                   http://www.contesting.com/km9p/search
>
>
----------------------------------------------------------------
Michael K. Walker                   Legato Systems (Canada) Inc.
Escalation Managment                     3390 South Service Road
(905) 637-4738                                    Burlington, ON
http://www.legato.com                                    L7N 3J5
pager:  1480111@pagemart.net

--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search