27 Jan
2013
27 Jan
'13
8:20 p.m.
Hi All,
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.
Les
Hi All
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
29 Jan
29 Jan
12:05 a.m.
New subject: FT-736R vs TS-2000
Hi Les,
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?
73
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.
Les
Hi All
>
>
>
>
>
>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
5 Feb
5 Feb
6:51 p.m.
New subject: FT-736R vs TS-2000
May be of some interest to a few..
New Webcast:
*Oscilloscope Techniques for Precisely Measuring Small Signals*
Do you need your oscilloscope to measure increasingly smaller electronic
signals and/or additional signal detail? Interest is growing in viewing
small current and voltage signals. Measurement of very small signals and
additional signal detail can be challenging due to noise of the scope,
scope settings, and probing. If you need your scope to precisely view
signals as small as a few millivolts or milliamps, or need higher
dynamic range measurements to see additional signal detail, this webinar
is for you. Learn what scope settings enable you to reduce noise and
increase vertical resolution.
Explore the relationship between bits of resolution and noise for scopes
with 8 and 12 bits of resolution. Get up to speed on new probing
technologies that enable scopes to see currents as small as 50 uA.
https://event.on24.com/eventRegistration/EventLobbyServlet?target=registrat…
Jerry
VE6CPP
DN39or
On 1/28/2013 4:05 PM, Leif Asbrink wrote:
Hi Les,
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?
73
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.
Les
Hi All
>
>
>
>
> 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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3775
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3784
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2 comments
3 participants
participants (3)
-
Jerry -
Leif Asbrink -
Les Listwa