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Re: AIDC-2733 gain measurement



Greg,

The three (or two) socket-head cap screws on each filter bear down on
the ungrounded end of the filter fingers with a bit of insulating
material (Teflon?) interposed, thereby forming a capacitor.  I'll ask
John Harrington to add the construction details for these filters, as I
have not actually had one apart.  He has, and I understand that he has
successfully re-peaked them for 2400 MHz (John, are you listening?).

You might need to go to Your Favorite Hardware Store to get an extra
screw to use in the blank hole.

You'd need a noise figure meter to do this right, but a sufficiently
weak 2.4 GHz signal source and a Mk 1 Mod 0 ear (not the tin one!) might
suffice.  You'd want to adjust for minimum noise figure, which is
equivalent to max. gain with min. noise.

I haven't actually tried this, but I know that others have.  Your
mileage may vary.  Caveat emptor.  Carpe diem!

regards,

Mahlon - K4OQ

greg wrote:
> 
> how do you tune that filter ?
> 
> GREG N8TDL
> 
> > Art,
> >
> > In stock configuration, the AIDC 3733's frequency response is specified
> > only down to 2500 MHz, so your results as stated are inconclusive.  Did
> > you measure its conversion gain anywhere else?  Did you re-tune the two
> > comb filters to 2400 MHz before you measured it, or are they still tuned
> > for the stock bandwidth?
> >
> > regards,
> >
> > Mahlon - K4OQ
> >
> > Art Goldman wrote:
> > >
<snipped>
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