But the whole reason for replacing bandpass filter switching diodes with
PIN diodes (as set out in Ulrich Rohde's articles in QST) was the
reduction of 2nd order intermod distortion, not improvement of
sensitivity. So, I think this is a red herring for a number of
reasons.... FWIW
73, Duane
> ----- Original Message -----
> From: <c-hawley@uiuc.edu>
> To: <tentec@contesting.com>
> Sent: Thursday, February 03, 2005 9:16 AM
> Subject: Re: [TenTec] Re: Paragon Question - Lack of sensitivity
>
>
> > If these are the diodes that switch in and out the input
> > band pass filters, you are better off with pin diodes which
> > switch much slower than 4148s. The reason is so that strong
> > incoming rf does not switch the diodes that are supposed to
> > be on (or off) for the band you are using. This was a big
> > issue which became popular about 10 years ago. There are
> > some kits available to convert the fast switching diodes to
> > pin diodes. But, don't go and wholesale replace every diode
> > in sight. I think some of these kits were somewhat ill
> > advised. Your receiver may use pin diodes already in many
> > places.
> > Chuck, KE9UW
> >
> > ---- Original message ----
> >>Date: Wed, 2 Feb 2005 15:35:58 GMT
> >>From: "ultrafixedwing@juno.com" <ultrafixedwing@juno.com>
> >>Subject: Re: [TenTec] Re: Paragon Question - Lack of
> > sensitivity
> >>To: tentec@contesting.com
> >>
> >>
> >>Will a 1N914/4148-Type Diode work in the Paragon front end?
> > It's a silicon switching diode. If so, I'll run out and get
> > a handfull.
> >>Thanks,
> >>Paul
> >>KS2S
> > _______________________________________________
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> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
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>
>
Duane Calvin, AC5AA
Austin, Texas
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