Is this not, to some degree, a function of the added stage of conversion? I
had noted this with the 580 Delta (2 of 'em) which was likely TT's first
double conversion rig, and predecessor to the Corsairs. I dismissed it as
the extra stage.
73'
Tom
N5OZQ
> ----------------------------------------------------------------------
>
> Date: Wed, 3 Sep 2003 20:24:51 -0400
> From: "Gary Hoffman" <ghoffman@spacetech.com>
> To: <tentec@contesting.com>
> Subject: Re: [TenTec] Noisey Corsair II
> I've noticed that all the Corsairs I've come into contact with (3) are
noisy
> compared to the Omni. I thought this was normal, due to higher IF gain.
> Is this right, or is it really a noisy FET ?? Is the fix below a valid
> fix, or is it just detuning the section and killing some of the gain ?
>
> 73 de Gary, AA2IZ
>
>
> ----- Original Message -----
> From: "denton" <denton@oregontrail.net>
> To: <tentec@contesting.com>
> Sent: Wednesday, September 03, 2003 7:33 PM
> Subject: Re: [TenTec] Noisey Corsair II
>
>
> > My Corsair II has a noisy fet or transistor on the if-af board. It is a
3
> > legged device and has a little ferrite cap on two of the legs. One can
> > locate the noise source by simply touching the metal cap with the rig
> > running. I simply put on an short 6 inch piece of insulated wire around
> the
> > metal cap and then ran the wire along the side of the main corasir's
case
> to
> > drain off the noise.
> > ----- Original Message -----
> > From: "Steve" <sswhite@mchsi.com>
> > To: <tentec@contesting.com>
> > Sent: Wednesday, September 03, 2003 1:55 PM
> > Subject: [TenTec] Noisey Corsair II
> >
> >
> > > I have been enjoying a new Corsair II and have just recently re-built
> the
> > PTO and it is now smooth as silk, it even approaches my FT-1000MP VFO in
> > terms of smoothness.
> > >
> > > I have noticed that the Corsair II has noticeably more background
noise
> > than my Omni-D has and I began looking around for the source of it. It
> > appears that it is coming from the PBT board since. When I disconnect
the
> > ouput of the PBT board which goes to the IF board it quites down very
> well.
> > Of cousre some background noise is to be expected and all of my comments
> > relate to no antenna connected. When I disconnect the input to the PBT
> > board it also has a small drop in background noise, but no where near as
> > dramatic as when I disconnect the PBT board from the IF stage. It
appears
> > to me that the noise source is really the PBT board.
> > >
> > > So the question is does any know of any historical problems with
noisey
> > PBT boards or what could be causing this. As you know the PBT board has
> two
> > mixers on it and I suspect one of those is the culprit since they can be
> > noisey at times..
> > >
> > > Steve NU0P
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