[Elecraft] SDR-IF and I/Q questions

[Bruce Beford]

Ed, 
Don's comments about a serial port being unnecessary was with respect to the
KX3 specifically, not the SDR-IQ. The KX3 will provide baseband "audio"
output, which will need to be fed into the stereo input of a soundcard on a
computer for panadapter capability. Think of it as having an LP-Pan built
in. 

If one wants "point and shoot" functions from the panadapter software, then
a USB/serial control port back to the KX3 will be needed. And yes, the KX3
will have that capability as it has already been announced that the KX3 will
use a subset of the K3 command structure. (there is a serial port on the
KX3). 

Also, a USB interface device for the KX3 is also in the plans from Elecraft.
It will connect to a USB port on the computer, and have the required
connector on the other end to plug directly into the radio. I hope this
helps clear up any possible confusion.

73,
Bruce, N1RX

(original message)

Don,

Not trying to be argumentative, but...

The SDR-IQ uses a USB-2.0 interface and not audio.  Some SDR actually 
provide A/D conversion inside the box with digital output 
streams.  The units you mentioned are audio-baseband.

The only issue would whether one needed a good soundcard or not.

I understand that many sw provide for radio control so need that 
access (whether via USB or RS232).  K3 being one of those that offer 
external control.  I wonder if the KX3 will have that ability, as well?

Very handy for the "click frequency" operations on sw like psk-31 
(variants).  The eme SDR sw (Linrad) that I am using has this ability 
(if proper drivers are available for the radio).

------------------------------

Message: 37
Date: Thu, 10 Nov 2011 07:42:12 -0500
From: Don Wilhelm <w3fpr at embarqmail.com>
Subject: Re: [Elecraft] SDR-IF and I/Q questions
To: elecraft at mailman.qth.net
Message-ID: <4EBBC6A4.4020700 at embarqmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Ed,

The I/Q outputs are baseband audio - just as would be the case with the
output of LP-Pan, or a Sofrrock receiver, or most any SDR receiver.  The
serial (or USB) port is only used when rig control is introduced in
addition to the panadapter function.

73,
Don W3FPR