K1 and FP U2

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K1 and FP U2

David L DuPuy
Don...  I was unable to find any further loose parts (from speaker
nut/washer) in the front panel area.  They appear to have lodged on the
rear panel, but could certainly have bounced around a bit.

As for weak signals, I was camping the the Yukon, so maybe why I was
hearing weak signals!

So it sounds like we are down to FP U2.  I don't look forward to trying to
replace it ! but guess I'm going to be trying.  That's an analog signal out
of pin 1?

I now notice that switching filters has no affect on the bandwidth...
 maybe that confirms that FP U2 is in need of replacement?  Can we rule out
the MCU?  Appreciate your help.  David
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Re: K1 and FP U2

Don Wilhelm-4
David,

The signal from U2 pin 1 is indeed analog.  In normal transmit it should
contain a square wave at the frequency of the sidetone pitch.  During
receive, the voltage level should change as you switch from filter to
filter.
If you have power control in the K1, then the other output from U2 is
working, and that rules out the MCU.

73,
Don W3FPR

On 7/1/2013 8:07 PM, David L DuPuy wrote:

> Don...  I was unable to find any further loose parts (from speaker
> nut/washer) in the front panel area.  They appear to have lodged on the
> rear panel, but could certainly have bounced around a bit.
>
> As for weak signals, I was camping the the Yukon, so maybe why I was
> hearing weak signals!
>
> So it sounds like we are down to FP U2.  I don't look forward to trying to
> replace it ! but guess I'm going to be trying.  That's an analog signal out
> of pin 1?
>
> I now notice that switching filters has no affect on the bandwidth...
>   maybe that confirms that FP U2 is in need of replacement?  Can we rule out
> the MCU?  Appreciate your help.  David
>

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Please help support this email list: http://www.qsl.net/donate.html