Key clicks

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Key clicks

Nanko-2

Unfortunately no reply's on my posting, so I guess
I have to dig deeper into the way the CW signal is generated,and do some
wave form checks.
To do this I need some help,because the schematic diagram does not help me.
I woulk like to know the signal path for CW ,I guess it starts with U8 but
then.......??

.mni tnx for your time  73  Nanko  PA0V





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Re: Key clicks

Don Wilhelm-3
Nano,

Sorry you didn't get a response earlier.

K2 keying starts in the microprocessor and exits the associated 8 bit DAC
(U8) as the V-PWR signal.  Then it is shaped in the ALC circuits and comes
out as the V-ALC signal (the level of this signal also controls the power
output level).  (The recent keying waveshape change modified components in
the ALC circuit area. - if you have a new K2, it is included)

The V-ALC signal activates Q24 (see schematic RF board sheet 2 - lower right
corner).
The signal then goes to the Xmit Mixer (U10) and then to the Buffer (U9) and
then on to the bandpass filters.  The output of the BPF then feeds the
Driver and Power Amplifier (sheet 4 of the schematic) and finally goes to
the T/R switch and Low Pass Filters.

I do hope that helps you find the problem.

73,
Don W3FPR

----- Original Message -----

>
> Unfortunately no reply's on my posting, so I guess
> I have to dig deeper into the way the CW signal is generated,and do some
> wave form checks.
> To do this I need some help,because the schematic diagram does not help
> me.
> I woulk like to know the signal path for CW ,I guess it starts with U8 but
> then.......??
>


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