LF: RE: MF tonite

["Ken" <ken.h.wright@btinternet.com>]

Hi Stefan.
What mechanical filter are you using?.
73.
Ken
M0KHW

-----Original Message-----
From: owner-rsgb_lf_group@blacksheep.org
[mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Stefan Schäfer
Sent: 12 September 2012 21:02
To: rsgb_lf_group@blacksheep.org
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

Am 12.09.2012 21:01, schrieb C. Groeger:
> Thanks, mal for these wise words!
> Df5qg (Homebrew&  CW)
>
> Christian Groeger
>
> mal hamilton<g3kevmal@talktalk.net>  schrieb:
>
>    
>> Never replace the MORSE KEY, you do at your peril !!
>> Other modes come and go but MORSE lives on
>> All Radio Operators know this.
>>
>> G3KEV
>>
>>