Hi Ken,
OK but later. I want to try some modifications, i.e. using the 500 Ohm
input and the 18 kOhm output, to have some gain. If this does not affect
the matching, i would prefer that...
73, Stefan
Am 13.09.2012 20:43, schrieb Ken:
Stefan.
Thank you for the info, maybe sometime you will be able to post the circuit?
73.
Ken
M0KHW
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Stefan Schäfer
Sent: 13 September 2012 12:26
To: [email protected]
Subject: Re: LF: Re: RE: MF tonite
Ah yes, Thomas was faster, damn ;-)
Another image from the experimental setup, using source followers
https://dl.dropbox.com/u/19882028/MF/Mechanical_filter_with_source-followers
.JPG
The results have been very good last night!
73, Stefan/DK7FC
Am 13.09.2012 13:12, schrieb Thomas Rosenkranz:
Hy Ken,
the name of the mechanical filter is FZ02
http://www.oppermann-electronic.de/html/hf-spezialbauteile.html
http://dm4tr.bplaced.net/index.php?section=Receiver
73
Thomas DM4TR
----- Original Message ----- From: "Ken"<[email protected]>
To:<[email protected]>
Sent: Thursday, September 13, 2012 10:28 AM
Subject: LF: RE: MF tonite
Hi Stefan.
What mechanical filter are you using?.
73.
Ken
M0KHW
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Stefan Schäfer
Sent: 12 September 2012 21:02
To: [email protected]
Subject: LF: MF tonite
Christian,
Are you QRV tonite? I would like to see or better hear the difference of
my RX performance when using my band filter i was testing in the
afternoon.
It is the mechanical filter which uses source followers at the input and
output, to provide a constant accurate impedance matching to keep the
passband ripple as low as possible. The afternoons tests have been very
promising, see https://dl.dropbox.com/u/19882028/MF/MF%20Filter.png
This is the frequency response:
https://dl.dropbox.com/u/19882028/MF/473%20kHz%20ZF%20Filter%2040%20dB.png
There should be a much better image rejection now and so maybe a few
more dB SNR... Unfortunately the filter does not cover the 502 kHz
region. But this problem will be gone in some months...
Will be on 472.5 kHz soon.
73, Stefan/DK7FC
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