Excellent! Thanks Jim! Sorry for missing that.
73, Barry N1EU
On Tue, Sep 13, 2016 at 2:33 PM, Jim Brown <k9yc@audiosystemsgroup.com>
wrote:
> Barry,
>
> Did you find the link to the data plots? It's two paragraphs above the
> Attenuation Tables. http://audiosystemsgroup.com/BandpassFilterData.htm
>
> 73, Jim
>
>
> On Tue,9/13/2016 10:53 AM, Barry N1EU wrote:
>
>> Nice report Jim! Data is given for ham band rejection but folks are not
>> going to find data for 41M and 49M shortwave band rejection.
>>
>> Barry N1EU
>>
>> On Tue, Sep 13, 2016 at 1:47 PM, Jim Brown <k9yc@audiosystemsgroup.com>
>> wrote:
>>
>> Several years ago, I measured a half dozen or so bandpass filter sets that
>>> I was able to borrow for NCCC members, and some that I owned. I wrote up
>>> a
>>> report, that was published in the National Contest Journal and the NCCC
>>> newsletter, "The Jug." That report, with links to the actual data for
>>> each
>>> filter on each band, is on my website. http://k9yc.com/BandpassFilter
>>> Survey.pdf The filter sets I tested were ICE, Dunestar, W3NQN sold by
>>> Array Solutions, and the very nice TXBPF set designed by Bob Henderson,
>>> 5B4AGN, based on a W3NQN design, and for which Bob did several group
>>> purchases. In addition, Bob sent me data that he measured on 4O3A filters
>>> rated for use on power amp outputs, and that data is in the report.
>>>
>>> 73, Jim K9YC
>>>
>>>
>>> On Tue,9/13/2016 1:17 AM, shristov wrote:
>>>
>>> "rick@dj0ip.de" <Rick@DJ0IP.de> wrote:
>>>>
>>>> However the Dunestar SPECS on their web site claim 40dB band-to-band
>>>>
>>>>> rejection. I was just quoting the specs.
>>>>> http://www.dunestar.com/store/Single-Band-Bandpass-Filters-pid-4.html
>>>>>
>>>>> Hi Rick,
>>>>
>>>>
>>>> that's what I had in mind.
>>>> Taking the 7 MHz filter as an example,
>>>> there is 40 dB attenuation on ~3.5 MHz.
>>>>
>>>> But on 6 MHz the attenuation is practically nil.
>>>>
>>>> Your preselector is the right tool for the job.
>>>> But it's receive-only, given the 7.5 dB passband attenuation.
>>>>
>>>> Dunestar etc filters must have a much wider passband
>>>> in order to achieve low enough passband attenuation,
>>>> making them suitable for transmitting.
>>>>
>>>>
>>>> Best 73,
>>>>
>>>> Sinisa YT1NT, VE3EA
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