[Elecraft] K3: KRC2 interface

[Bill Coleman N2BC]

Hi Don,

Do you mean the K3 AUX I/O Pin 10 "KEYOUT-LP" line?   The purpose of this 
line is a bit fuzzy, to me anyway.

I based my KRC2 'needs' list based on page 21 of  the KRC2 manual.

The paragraph at the top of the page states that the minimum required for a 
K2 are:

W16 - AUXBUS
W18 - 12V (can be provided via external source)
W19 - 8R
W21 - to pass PC serial info to K2 (not needed in K3)
W23 - ditto W21

Table 3 states that the KRC2 uses 8R to determine TX/RX status, I would have 
thought to inhibit band changing while transmitting.

I just tried the KRC2 without feeding it 8R from the K2 (W19 pulled).  8R is 
indeed not 'needed' to handle the band info from the AUXBUS.  Tried changing 
bands on the K2 while key down or asserting PTT - it won't change.  But the 
K2 remembers the band change key press and does change once key down or PTT 
is dropped & the KRC2 follows.

Anywho, it looks like the K2 is smart enough to not change bands while in TX 
& the KRC2 will follow the AUXBUS as/when ordered.  I'm sure the K3 is at 
least that smart [  ;-)  ]  So I amend my KRC2 "needs" list to simply AUXBUS 
and ground - GREAT!

73,  Bill  N2BC


----- Original Message ----- 
From: "Don Wilhelm" <w3fpr at embarqmail.com>
To: "Bill Coleman N2BC" <n2bc at stny.rr.com>
Cc: "elecraft" <elecraft at mailman.qth.net>
Sent: Wednesday, January 30, 2008 9:48 AM
Subject: Re: [Elecraft] K3: KRC2 interface


> Bill,
>
> The KRC2 does not need the 8R input for use with the K2 or K3.  Look at 
> page 20 of the KRC2 manual and you will see that the KRC2 uses 8R only as 
> an analog input.
>
> The KeyOut signal timing is equivalent to the K2 8R signal.
>
> 73,
> Don W3FPR
>
> Bill Coleman N2BC wrote:
>> Just doing some planning for the eventual arrival of my K3.
>>
>> The KRC2 needs AUXBUS 8R and ground.  Where / what on the K3 AUX I/O 
>> connecter is 8R or it's equivalent?
>>
>> Thanks!
>>
>> 73, Bill   N2BC
>>
>