Sorry to be a wet blanket, but now that the AM broadcast
band extends to 1.7 MHz, you really have to use an
elliptic function (AKA Cauer) filter, not a Chebyshev.
There are several of those on the market (don't have
the info handy).
Rick N6RK
On 11/25/2010 8:10 AM, Joe Subich, W4TV wrote:
>
> Hijacking an old e-mail for new information ...
>
> For those looking for solutions to eliminate/reduce overload from
> nearby AM broadcast transmitters, Jack Smith, W8OZA at Clifton
> Laboratories now has two interesting products.
>
> Model Z10022A is 9th order 1 dB Chebyshev highpass filter that
> claims 1.6 dB insertion loss at 1.8 MHz, ~ 30 dB at 1.6 MHz,> 40
> dB at 1.5 MHz and ultimate rejection around 100 dB below 1 MHz.
> See:<http://cliftonlaboratories.com/z10022a_high_pass_filter.htm>
>
> The other filter is a band stop (band rejection) filter for the
> AM band. The Z10020 allows reception below 540 MHz for those who
> are also experimenting at VLF or DX the NDB band. See:
> <http://cliftonlaboratories.com/z10020_am_medium_wave_band_reject_filter.htm>
>
>
> I have no connection to Clifton Laboratories but since the "how
> to deal with AM interference/overload" issue pops up periodically,
> I wanted to get this information into the archives in case anyone
> else needs it.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 1/22/2007 6:27 PM, Tod-MN wrote:
>> Has anyone more information regarding the schematic and values for this
>> filter? Is it commercially available or is it 'one of a kind' and made of
>> unobtanium?
>>
>> Tod, K0TO
>>
>>>
>>> http://www.dallas.net/~jvpoll/Filter/TheAMBrickWall.html
>>>
>>
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>> Topband@contesting.com
>> http://lists.contesting.com/mailman/listinfo/topband
>>
>>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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