Hi Stefan.
Fully understand.
73.
Ken.
M0KHW
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Stefan Schäfer
Sent: 13 September 2012 20:03
To: [email protected]
Subject: Re: LF: Re: RE: MF tonite
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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