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On 1/28/2013 4:05 PM, Leif Asbrink wrote:
It is not clear to me what you mean here. How did you
measure the noise drop? Was wsjt running on the output
from Linrad or on some other hardware?
I do not know the details on how the noise floor is computed
in wsjt. If you look at the Linrad S-meter any signal
within the passband would be included in the computed
RMS power. Probably not so in wsjt.
"Different audio cards" It is unclear to me how that enters
the picture. What is the signal path in both cases?
Leif / SM5BSZ
In the past, I seem to remember that I found that
the accuracy of measuring
the " noise drop" was very much different when I used WSJT as compared to
using Linrad, with a difference if several db with the same preamp. Can
anyone confirm? It could be the fact I was using different audio cards.
> Thanks for the input on these two radios
> Just to let all know I have always run a mast
> mounted lna designed by
> VE7BQH .25nf/19db which has worked very well for me on EME
> I think for a comparison i will get the TS-2000
> receive modified as per Russ K2TXB just to try
> to see if there is any difference between the 736r and my TS-200
> Hope to some comparisons to report over the next month or so
> Thanks Ian VA7SW//VE7IRA
> BTW when working EME I have on WSJT the RX DB
> set to 0 when I turn per amp off there DB on
> WSJT goes to ?15 so the pre amp is definitely working
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