[NA-User] More LPT for CW and external voice keyer

Scott Dickson shdickson at allvantage.com
Thu Nov 4 15:29:00 EST 2004


Boy! I sure left the whole story out.

NA 10.59 on PC with dual boot Win 98.  Using boot menu to go straight to 
DOS command prompt.  Have an I/O card with hardware jumpers to set IRQ and 
addresses for 4 serial and 3 parallel ports.  This is my contesting 
computer, not used for anything else.

I currently utilize rig control on Com 1, KAM TNC on Com 2, and CW(with 
paddle inputs) on Com 4.

I recently bought IC756Pro2, and built an outboard box (like the I-Mate) to 
trigger the internal DVK and CW memories.  I wanted to improve on that 
circuit to 1) incorporate CW and 2)add NA control of the external DVK as 
shown on page 56 of the NA manual; however I did utilize optoisolators in 
place of the transistor switches.  I can apply 2 - 5 vDC to the LPT inputs 
to my external box, and it triggers/works fine.

In the past for Field Day, I built an LPT CW interface from the schematic 
in the NA manual.  That interface has been used by our club every year at 
FD, but on a different computer.  That interface won't work on this 
computer in question.

I have checked to the best of my ability using both VOM and o'scope to 
determine if any signal is coming down the LPT cable from the computer, 
both for CW sending and external DVK triggering.  Also cannot get the 
paddle inputs to affect anything in the NA software on the LPT ports.

So, at this point from my logic I have either:
1.  A bad LPT cable
2.  3 bad LPT ports on the I/O card
3.  Made a stupid mistake or omission in the setup / config of my software.

I'm really hoping for option 3, then option 1.  Option 2 is bad.

--Scott



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