Date: Fri, 16 Mar 2018 11:53:28 -0700
Reply-To: Alistair Bell <albell@SHAW.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@SHAW.CA>
Subject: Re: Thought problem for Friday
In-Reply-To: <024a01d3bd54$c0708b20$4151a160$@gmail.com>
Content-Type: text/plain; charset=utf-8
Ok, ok.
Have a look at the brake lights when someone presses pedal. See if flickers.
Yeah, I’m going down a blind rabbit hole.
Ab
> On Mar 16, 2018, at 11:29 AM, <stuartmacm@gmail.com> <stuartmacm@gmail.com> wrote:
>
> Nothing explains the frequency change with pressure. I can play a tune while coming to a stop, and then it stops. Static electricity from the brake pads interacting with the LED's? Piezo electric effect? Cosmic rays? Gasoline bacteria? Trolls & gremlins?
>
> Stuart
>
> -----Original Message-----
> From: Vanagon Mailing List <vanagon@gerry.vanagon.com> On Behalf Of Alistair Bell
> Sent: Friday, March 16, 2018 10:02 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Thought problem for Friday
>
> It’s the led lights.
>
> I bet there is a PWM or some circuit in there somewhere on the led . The light bar perhaps.
>
> I notice radio interference when my led back up lights engaged. Also had issue of severe interference with my first go round of H4 led bulb experiment.
>
> Strangely though, the offending h4 bulbs produced no interference in friends van. So seems some radio installs more sensitive than others.
>
> Alistair
>
>> On Mar 16, 2018, at 9:40 AM, OlRivrRat <OlRivrRat@COMCAST.NET> wrote:
>>
>> Since the Brake Light Circuit is a simple On/Off Circuit I
>> would doubt that it is the
>>
>> the Lights that are the cause ~
>>
>> My guess is that somehow the Brakes Themselves are Generating
>> an RF Noise Signal ~
>>
>> Hopefully 1 of our Resident Electronics Gurus will have the answer ~
>>
>> ORR ~ DeanB
>>
>>> On 16 Mar , 2018, at 10:25 AM, Stuart MacMillan wrote:
>>>
>>> Figure this one out:
>>>
>>>
>>>
>>> When I depress the brake pedal I hear a faint high pitched "whine"
>>> from the radio. It's pitch (frequency) changes with pedal pressure
>>> (higher with more pressure), and only happens on AM stations.
>>> Unfortunately, my favorite sports radio stations are AM so I hear it often.
>>>
>>>
>>>
>>> It didn't change with a new radio last year, and I do have LED brake
>>> lights and the GW high mounted LED brake light. Brake light switches
>>> have not been replaced. Whine was there with the 1.9 engine and is
>>> unchanged with my '93 Subaru 2.2 engine conversion. I have not
>>> switched the bulbs back yet, but I'll give that a try and see if it goes away.
>>>
>>>
>>>
>>> It's just a nuisance, but I'm stumped, particularly by the change in
>>> frequency with pedal pressure. Any ideas why LED brake lights might
>>> cause this? Maybe install a capacitor on the radio like this?
>>> https://www.amazon.com/PAC-CSS12-Passive-Filter-Capacitor/dp/B000CEDZ
>>> BA
>>>
>>>
>>>
>>> Stuart
>>>
>>> '85 Westy
>
|