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Re: uBITX SSB filter response question #ubitx

 

In both the curves without and with transformer your filters loss appears to be around -7 db's
In my opinion this is bit too high -3db is just right up to -5db is acceptable according to the
experts, what type of capacitors are used in this filter? The multi layer ceramic capacitors
are really of lo loss. If you use the modern SMD ones in my opinion that will reduce the loss
in the filter? ?

Virus-free.

On Fri, Apr 13, 2018 at 9:35 PM, Michael LeBlanc <michaelleblanc1@...> wrote:
Thanks Rod. I'm enjoying the journey and for the time being I can get on the air any time with my appliance radio. ;-)

I was measuring it 'naked', without the transformers. Just before reading your reply, though, I measured it again but through the transformers, and the result is "softer":

I also was fastidious about recording the individual crystal measurements, and (like you), put them in a spreadsheet and asked it to re-order the crystals by centre frequency. Thanks also for your thoughts on the filter's centre frequency. As long as I'm in the ballpark, I'm happy.

-Michael VE1LEB
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