[TenTec] Argonaut V-Jupiter-Signalink USB and Digital

Dr. Gerald N. Johnson geraldj at weather.net
Mon Dec 20 09:36:03 PST 2010


If the input impedance is really 47 ohms, you could use a T or an L or 
simply a single series resistor. Think about 4700 ohm series resistor. 
With that 47 ohm input Z that would drop the audio 100:1. Maybe simpler 
than a complete cable, how about a pair of connectors back to back with 
straight wires for all but that audio line. A little metal box would be 
of benefit to maintaining the shielding.

Or if the interface to the USB dongle is a DE9 with a metal shell, it 
might be possible to mount a tiny switch in that shell to insert the 
4700 ohm resistor or short it out depending on the rig.

73, Jerry, K0CQ

On 12/19/2010 5:08 PM, Fred Moore wrote:
>
>
> On Sun, 2010-12-19 at 15:03 -0800, James C. Owen, III wrote:
>
>> Not wanting to re-engineer something that likely already has been done. Here's
>> my problem! Recently  got on the digital modes with a signalinkUSB that works
>> fine with the Argonaut V, all gain controls pretty much centered. Connected to
>> the Jupiter and had nothing but overdrive even with all gain controls at
>> minimum. I then looked at the spec's of the two. Argonaut V 100mv into 47 ohms,
>> Jupiter 1mv into 47 ohms. So the Jupiter is 100 times more sensitive, so that's
>> the problem. I'm thing of a simple T attenuator  which will require me to make
>> another cable. Has anyone come up with a good simple solution?
>> 73 Jim K4CGY
>>
>>
>>
>>
>> _______________________________________________
>> TenTec mailing list
>> TenTec at contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>
>
> Havn't had the manual for the signalinkUSB for some time, but isn't
> there a jumper inside between two pins?  perhaps a switch added to the
> signallink moving the jumper? in and out.  You could also just change
> the master output for the USB device in the software depending on what
> rig you are driving.. . . Fred
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>


More information about the TenTec mailing list