[Elecraft] [K2] 8T signal at J13

[Don Wilhelm]

Steve,

Well, that is another interesting development.  Just how does it 
interrupt the 8T voltage to the PA bias (Q11 and Q13)?  It would not be 
good to short the 8T line, because that would just draw current and 
cause many parts of the transmit section of the K2 to not work.
Opening the RF path to the K2 driver and PA would be a better way of 
doing things.  In other words (like the K60XV), opening the path between 
J13 pins 3 and 5 (with jumper W6 removed) would do that task.

73,
Don W3FPR


On 2/10/2015 11:06 PM, Steve Kavanagh wrote:
> Thanks, Don.  That is what I was figuring too, but I wanted another pair of eyes on it!  The TIK2 uses both the 8R and 8T lines - typically 8R is used for transverter PTT, while 8T is (optionally) used to switch the bias to the K2 PA to ensure it stays off when using the transverter.  I think it would probably be ok to leave it unconnected, but I'm just reviewing my options. 73,Steve VE3SMA
>        From: Don Wilhelm <w3fpr at embarqmail.com>
>   To: Steve Kavanagh <skavanagh72 at yahoo.ca>; "Elecraft at mailman.qth.net" <Elecraft at mailman.qth.net>
>   Sent: Tuesday, February 10, 2015 6:30 PM
>   Subject: Re: [Elecraft] [K2] 8T signal at J13
>     
> Steve,
>
> As far as I can determine, no harm would come from making that connection.
> IMHO, it would be better to invert the 8R signal, but then I did not
> have any 'say' in the DEMI design.
>
> 73,
> Don W3FPR
>
>
>
> On 2/10/2015 4:07 PM, Steve Kavanagh wrote:
>> I was given a DEMI TIK2 transverter interface board which I would like to install in a K2.  It requires the 8T signal on pin 6 of J13 on the RF board, which was there on early K2s but not on more recent versions.  Can I just connect together the pads marked "X" and "8T" (on page 9 of the K60XV manual for example) ?  Or will this make weird things happen?  Obviously I'd have to break this connection if I wanted to swap in a K60XV instead. 73,Steve VE3SMA
>>
>
>
>    
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