Rigblaster Nomic / Behrenger mixer-EQ

[KB9WQJ]

     I have an interesting possible solution to a problem that I have been thinking over.  I would like to present it here since it doesn't fit anywhere else really.  It may relate to the earlier thread about recording both sides of a QSO.
     I have an Icom 735.  I wish to use the ACC-1 jack (with West Mountain's cable) to get line level AF from the radio.  This will go to a line input on the Behrenger.  The Nomic will connect to the rig mic jack in the usual way and to the computer serial port in the usual way.  The computer output will go to an input on the Behrenger.  The audio main out from the Behrenger will go to the Nomic audio input jack.  The sound will get to the computer for decoding  from the Behrenger control room monitor out jack.  Needless to say, all inputs and outputs to/from the Behrenger are level adjustable.  Will this work?  The only potential problem I see with it is that the computer will receive it's own audio back through it's input from the Behrenger control room out simultaneously as it is sent to the Nomic (and thence to the radio).  Will the computer have a feedback loop problem as it sends it's output to the Behrenger (for mix and send to the Nomic) and gets it back from the Behrenger at the same time?  I really want to have the Behrenger in the audio portion of the loop so that I can use a studio mic and adjust my transmit SSB audio.  I want to use the Behrenger unit for this and the Nomic unit seemed like an ideal way to get the mic audio from the Behrenger to the radio.  I know I will not have PTT through the Behrenger, however looking at the pin-outs on the ACC-2 (yes 2 not 1) din jack on the radio, it looks like I can make up a PTT switch jack using pins 2 and 3 (as long as I don't wish to use an autotuner with this jack, which is what it is for).  Then I can plug any old footswitch or handswitch into this jack and be able to control PTT that way.
   Another benefit to this setup would be that I would have tape out jacks on the Behrenger unit that using this setup would get both sides of a voice SSB QSO for taping or whatever.
   Has anyone tried this?  Any opinions?  I tried playing an MP3 while connecting one of the soundcard's two speaker outputs to it's own line input.  I turned ON all inputs and heard no change in the audio...no feedback at all, which is encouraging.
    The only other thing I can think of is a Rigblaster Plus and a W2IHY 2 band.  I can then get transmit audio from the Rigblaster line out to a tape deck but how do I get the receive audio from the radio to the same tape deck?  Also, this costs more (budget constraints).
     Thanks for any help or insight.  The big question is the feedback part from the computer to the Behrenger.

[N1LF]

I am using a similar set up with my Icom 746.I use
a Behrenger mixer and a Rigblaster Nomic in
just the way you descibe with no problems.

I feed the rear panel ACC jack with the mixer
to drive the balanced modulator directly. So far
no problems with RF or feedback. I did take the
extra precautions of using double shielded "data"
type cables, audio isolation transformers,
and ferrite chokes on all cables...so your
mileage may vary.

Also, you might be interested in posing this
question on our new ssb audio discussion
forum.

You can join by going to:

http://groups.yahoo.com/group/ssbaudio/



73,

Les Rayburn, N1LF

[KB9WQJ]

Thanks.  I've got it all set up now but have yet to make any voice or data QSOs with it.  I intended to post my experiences with it, perhaps with a diagram of how it is all hooked up to anybody that wants one.  I have yet to draw a nice diagram yet, but I will when I get time.  With 3 kids, and overtime job and a long commute it's hard to find ham radio time, but I manage to squeek some in.  I did get decodable audio at the computer so that works.  And I did "transmit" into a dummy load and listen with an extra receiver with a whip but it is hard to talk and listen to oneself in headphones at the same time...the bone conduction sound gets all mixed up with the recieved sound so all I could do was get levels sort of "ballparked".  I intend to find a nearby friend and have a low power QSO to tweak things.  Then I will try to have a digital QSO.  I am using the ACC-1 jack on the Icom 735 to get audio to the soundcard and I intend to homebrew a DIN plug to ACC-2 to concoct a PTT switch to install on the desktop mic stand from Radio Shack.  I intend to grab the PTT and grd on the ACC-2 DIN jack and run that to a low profile SPST momentary switch I intend to mount in the mic base (drilled through the cast iron base and switch installed in the hole).  Vox seemed to work for my tests but having all the audio going to the mixer and thence to the Rigblaster makes me leery of vox...any stray audio in the Behrenger would trip the vox and I just can't have it that chancy.  PTT makes me feel better.
Sorry about the long-winded post but perhaps someone else can use my experiences.  Anyone please email for the diagram of what I have done.  It took a number of adapters to get everything hooked through the Behrenger but the results so far seem to be worth it.  I also found a place that has the little Behrenger fairly inexpensively.   www.musiciansfriend.com for about $70.
73 to all.
Mike