Russ Edmunds <wb2bjh@...>
--- On Sun, 7/20/08, bbwrwy <email@example.com> wrote:
I have a question or two on recording DX from a ULR.
I realize the recorder has to share the receiver's audio output with
the headphones. But how do you handle the impedance mismatch between
the receiver and recorder?
In keeping with our ultralight theme, do you prefer a mini-disc or
solid-state digital recorders over cassette tape? Does anyone have
any recommendations in this area? Thus far I leaning toward a
mini-disc recorder which I understand is already obsolete.
Thanks for the help.
Ordinarily, I use an impedance matching transformer to match from most radios. Your typical headphone output is 4-8 ohms; your typical computer sound card wants to see something in the 5000-10000 ohm range ideally. I've found that 100, 2000 or 2500 ohms output is usually sufficient.
HOWEVER, there's another issue with ULR's which doesn't seem to exist even with my Sony 2010, and that's transmission of both monitor and CPU noise. Even with a 6 or 10' extender to get the ULR physically away from the computer so as to eliminate radiated noise, I still have way too much of it getting through, even using both my matching transformer and also a RS ground loop attenuator.
I haven't managed to correct this so far...
Blue Bell, PA ( 360' ASL )
[15 mi NNW of Philadelphia]
40:08:45N; 75:16:04W, Grid FN20id
FM: Yamaha T-80 & Onkyo T-450RDS w/ APS9B @15'
AM: Modified Sony ICF 2010 barefoot