On 11/18/20 7:15 PM, Richard (Rick) Karlquist wrote:
On 11/18/2020 5:27 PM, jimlux wrote:
The proposed mitigation technique relies on tracking the
rapid gain variations in the radiometer due to 1/f noise and
correcting them by generating a baseline state in the first
amplification stage of
Attached is the block diagram of the receiver in essence an amplifier for which
the effective input is gated/chopped on and off by turning the amplifier input
FET on and off.
Bruce
> On 19 November 2020 at 16:15 "Richard (Rick) Karlquist"
> wrote:
>
>
>
> On 11/18/2020 5:27 PM, jimlux
On 11/18/2020 5:27 PM, jimlux wrote:
The proposed mitigation technique relies on tracking the
rapid gain variations in the radiometer due to 1/f noise and
correcting them by generating a baseline state in the first
amplification stage of the low noise amplifier (LNA). The
proposed 1/f noise
On 11/18/20 4:59 PM, Richard (Rick) Karlquist wrote:
I suspect that, whatever this is, only applies to 1/f mechanisms
specific to THz, based on the last sentence. One of my
former clients did a PhD at Stanford on 1/f noise and
his dissertation certainly had no magic bullets to
mitigate 1/f
I suspect that, whatever this is, only applies to 1/f mechanisms
specific to THz, based on the last sentence. One of my
former clients did a PhD at Stanford on 1/f noise and
his dissertation certainly had no magic bullets to
mitigate 1/f noise.
There is some frequency, which I am fairly sure is
There is a paper from the univ of Twente in NL that
seems to indicate that it takes some time in an open
FET until the traps in the channel build up, so switching
the FET off in a regular way might be an advantage.
I stumbled across it when I was seeking input for my
ultra-low-noise chopper
Hi
If you dig into the data on the antennas …. ( they are fully tested and
doccumented …)
The Novatel design does a *very* good job. Indeed they are *much* better than
an old style
giant choke ring design. Normal list price is roughly 10X what that listing
shoed. Similar antennas
normally
Its just another variation on the principle of the Dicke radiometer.
In their case the amplifier input device is turned off periodically by
modulating its gate bias.
https://www.engr.colostate.edu/ece/faculty/reising/pdf/journals/Ogut_et_al_T-TST_2020.pdf
Bruce
> On 19 November 2020 at 12:38
On 11/18/20 2:49 PM, Charles Steinmetz wrote:
Stu wrote:
>> The usual auction site has a few true survey grade antennas for a
very good
>> price. Search for Novatel GPS-703-GGG. These cover all three frequency
>> bands (L1, L2, L5), which is still unusual to find in surplus.
Bob wrote:
On Wed, 18 Nov 2020 19:13:00 + (UTC)
Bruce Hunter via time-nuts wrote:
> Can anyone who subscribes to these transactions report on this? I dropped my
> subscription.
> In this letter, a novel 1/f noise mitigation technique is presented to
> improve the receiver 1/f noise performance of a
Stu wrote:
>> The usual auction site has a few true survey grade antennas for a
very good
>> price. Search for Novatel GPS-703-GGG. These cover all three frequency
>> bands (L1, L2, L5), which is still unusual to find in surplus.
Bob wrote:
….. and now they all seem to have been sold
If
Can anyone who subscribes to these transactions report on this? I dropped my
subscription.
In this letter, a novel 1/f noise mitigation technique is presented to improve
the receiver 1/f noise performance of a 670 GHz receiver. Time domain 1/f noise
corrected samples are compared with samples
I see that Mark Sims examined this Navicom GPSDO in March 2019 (EEVblog).
https://www.eevblog.com/forum/metrology/navicom-rcgd-m-gpsdo/
gb
==
Date: Sat, 14 Nov 2020 15:52:08 -0600
From: Greg Beat
To: time-nuts@lists.febo.com
Subject: [time-nuts] Surplus Navicom GPSDO
Surplus Navicom RCGD-M units
Hi
….. and now they all seem to have been sold :)
Thanks for the heads up !!!
Bob
> On Nov 18, 2020, at 3:56 AM, Stewart Cobb wrote:
>
> The usual auction site has a few true survey grade antennas for a very good
> price. Search for Novatel GPS-703-GGG. These cover all three frequency
>
The usual auction site has a few true survey grade antennas for a very good
price. Search for Novatel GPS-703-GGG. These cover all three frequency
bands (L1, L2, L5), which is still unusual to find in surplus.
(No connection to seller, just passing along a good deal.)
Cheers!
--Stu
15 matches
Mail list logo
