[Elecraft] K3-PSK/RTTY Question

[Tom Azlin N4ZPT]

Hi Bill,

Good deal on the order in!  As soon as they get past midnight then you 
should be close.

I have a whole handful of small transformers both from digikey and radio 
shack we got for club interface project. And bunches of optical coupled 
Darlingtons. And perfboard I used in the past. Also have a breadboard 
that just has three transformers ( for dual receive) with pairs of RCA 
connectors.

I first just connected the cables directly to my laptop but the 
hum/noise was not acceptable. Even pulled the AC cord on the laptop and 
ran on batteries. But then I expected that based on early interfaces for 
my other pre-K3 radios.

and back to the start of this thread. yes, the SignaLin-USB should be 
fine also. Especially if you happen to have one handy.

73, tom n4zpt

On 5/3/2012 3:35 PM, Bill Conkling wrote:
> Welllllllllllllll....
>
> My KX3 is on the list, I'm near the top of Dec 28 (00:23:59) so I am not
> sure at this point.  I have a circuit board that has holes for a couple of
> iso transformers, and a pot.  Will prob put something together using it when
> it gets here.
>
> Anxious in Williamsburg,
>
> bill   nr4c
>
> -----Original Message-----
> From: Tom Azlin N4ZPT [mailto:tom at n4zpt.org]
> Sent: Thursday, May 03, 2012 12:49 PM
> To: elecraft at mailman.qth.net
> Subject: Re: [Elecraft] K3-PSK/RTTY Question
>
> Hi Bill,
>
> For my K3 I do just as you say. A serial cable plus two audio cables
> connected to the line in/out of my computer sound card and my K3. Tossed
> my homebrew interface I used with my FT-1000 in the parts box.
>
> However my laptop does not have line in/out and so far the KX3 does not
> have line in/out. I get odd noise that looks like hum plus some scruff
> when I connect my KX3 directly to my laptop. It works but do not want to
> transmit the noise. So some sort of isolation and level adjusting is
> needed beyond just the computer sliders and KX3 mike gain and speaker
> level adjustment. Seems to me that is.
>
> So for my KX3 I just picked up the TRRS and TRS right angle connectors
> and plan to hook up one of my unterminated SL-USB cables ( short
> Ethernet cut in half) to play. Given the SL-USB is in my go kit anyway
> with my laptop.  May use one of the inexpensive interface boards I found
> on eBay with a couple transformers and transistor switch. Or just grab
> some resistors and audio isolation transformers out of my parts boxes,
> i.e. dust off my old interface board.
>
> So yes, with the KX3 seems an interface is needed. Was very happy to
> read that in the future a firmware update might include having the
> speaker out and microphone in be switched to line out and in for  the
> data modes.
>
> What do you use with your KX3???
>
> 73, tom n4zpt
>
>
> On 5/3/2012 9:32 AM, nr4c wrote:
>> Hi, Steve,
>> \
>> I really think the SL-USB is a real nice interface if you need an
>> interface.  But in my opinion, for the K3/KX3 it is over-kill.  I use
>> two stereo audio cables between the sound card and the K3 and it works
>> just fine.  The K3 is already buffered and isolated with transformers
>> (KX3 will not be).  Unless you need the sound card for computer sounds
>> and/or other audio uses, I'd just use the computer sound card.  PTT can
>> be handled via the serial CAT cable.
>>
>> ....bill  nr4c
>>
>>
>> On Thu, 03 May 2012 07:32:45 -0400, Steve wrote:
>>> Good Morning All,
>>> I have a K3 and am awaiting my KX3....soon I hope...
>>> My question is that I am wanting to put the K3 on
>>> PSK and RTTY and I'm wondering if
>>> my choice of the Signalink USP  is a good choice
>>> for these modes with the K3 and hopefully the KX3
>>> Tnx es VY73'
>>> Steve W8CRH
>>> SEMPER FI