[TenTec] Re: Paragon Question - Lack of sensitivity

[Steve Baron - KB3MM]

There were a couple of good articles by
Cornell Drentea - Communications Quarterly maybe.

What's the old saying  Fools walk in where angels fear to tread?<gr>

It's not hard to replace a diode but ....

The OMNI V actually uses BA482 diodes which were described as VHF switching
diodes by Siemens.

----- Original Message ----- 
From: "Duane A Calvin" <ac5aa at juno.com>
To: <tentec at contesting.com>
Sent: Thursday, February 03, 2005 16:19
Subject: Re: [TenTec] Re: Paragon Question - Lack of sensitivity


> 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 at uiuc.edu>
> > To: <tentec at 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 at juno.com" <ultrafixedwing at juno.com>
> > >>Subject: Re: [TenTec] Re: Paragon Question - Lack of
> > > sensitivity
> > >>To: tentec at 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 at contesting.com
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> >
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> >
> >
>
>
> Duane Calvin, AC5AA
> Austin, Texas
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