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Subject:
Re: Interesting RFI Problem
From:
Tom Behler <[log in to unmask]>
Reply To:
For blind ham radio operators <[log in to unmask]>
Date:
Tue, 8 May 2012 19:43:57 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (79 lines) 
    Howard:

I will definitely try this if things continue not to work, and my 
stubbornness gets the best of me in terms of freeing this speaker from RFI.

Time will tell, though, what I'm able to do in the way of additional fixes, 
or whether I just give up the ghost and keep things as they are by sticking 
with the other speakers that I know work.

73 from Tom Behler: KB8TYJ

----- Original Message ----- 
From: "Howard, W A 9 Y B W" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, May 08, 2012 5:08 PM
Subject: Re: Interesting RFI Problem


> Tom,
>
> If the shorter  shielded cable coiled to be as short as possible does not
> work and you like to tinker, try this:
>
> connect a 0.01 microfarad capacitor across the two audio connections in
> other words, from the audio hot lead to ground which is the shield of the
> cable.
>
> With the  following value capacitor the capacitive reactance will be as
> follows:
>
> at 10 kilohertz = 1.592k Ohms
>
> at 1 megahertz = 15.915 Ohms
>
> As you can see, the capacitor will not short out the audio signal because 
> of
> its 1.5 K ohm value at 10 kilohertz.
>
> At 1 megahertz the capacitor will almost be a short at 15 ohms.
>
> And at higher R.F. frequencies the reactance will be even lower.
>
> I am not sure at which end of the cable this capacitor will work best, you
> experiment.
>
> 73's
>
> Howard, #3
>
> ----- Original Message ----- 
> From: "Tom Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, May 08, 2012 2:30 PM
> Subject: Interesting RFI Problem
>
>
>>    Great suggestion, Howard.
>>
>> Thanks!
>>
>> Tom Behler: KB8TYJ
>>
>> ----- Original Message ----- 
>> From: "Howard, W A 9 Y B W" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Tuesday, May 08, 2012 3:12 PM
>> Subject: Re: Interesting RFI Problem
>>
>>
>>> Tom,
>>>
>>> When you try another cable, use as short of one as you can find to reach
>>> and
>>> if there is excess, coil it up in a small coil and hold it together with
>>> bread ties and if it works replace them with cable ties.
>>>
>>> 73's
>

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