[Elecraft] Re: The K1 and the Kent - Part 2

[k4zm]

Carlos:

I see why you had a problem with the Kent paddle.  The Dot side had to have
had dirty contacts.  Looking at the schematic of the K1 in the keyer input
you will notice that the dot and dash lines never go to the keyer ic chip.
Only a single line goes from the the key jack to the microprocessor.  Most
keyers use both the dot and dash levers in the keyer circuit.  The way the
microprocessor knows it is a dash or a dot is determined by what resistance
the KEYIN pin sees during contact closure.  If you close the DASH lever it
sees 39K and if you close the Dot lever it sees 20K.   I suspect that your
dot contact on the Kent had enough corrosion that the first time you closed
it it was causing the KEYIN line to see a resistance higher than 20k, so it
assumed it was to be a dash.  However after a few closures the contacts
started to working ok but were boarder line....  That is my story and I am
sticking to it. ..LOL

73
Jim Younce K4ZM
K2  SN:18
----- Original Message -----
From: "Carlos A Archilla" <caab@caribe.net>
To: "k4zm" <k4zm@comcast.net>; "Tom Hammond N�SS" <n0ss@earthlink.net>
Sent: Saturday, December 21, 2002 8:01 PM
Subject: The K1 and the Kent - Part 2


> Hello Jim and Tom,
>
> The problem turned to nightmare when I tried the Kent on my Icom 737A and
it
> worked perfectly! Back on the K1, the problem persisted but as time passed
> by it wasn't as frequent so I turned to some deep cleaning of the
contacts,
> I mean light sand paper, as I tried the coarse paper route and didn't
> worked. I think that scraping did the trick! What I would never understand
> is why the K1 was acting up and not  the Icom?
>
> Thanks very much gentlemen for your help and interest, you were very
> helpful.
> I wish you both a very Merry Christmas and Happy New Year 2003.
> Take care & 73's
> Carlos KP4GL
>
>
>