[HBR] 85Khz IF Transf.

[Peter Bertini]

I'd be interested in hearing about the taps and their purpose as well. I've
read that they were used to reduce stage gain; and I'd suspect they might
also reduce the loaded Q of the coils? Does anyone have a definitive
answer?  I plan on using 6EH7s in the IF stages, and I might need to "burn
up" some gain...

Pete

On Thu, Dec 11, 2008 at 11:17 AM, Tony <cybrlnk at yahoo.com> wrote:

> Tnx for the info Darrell.
>
> One other question comes to mind here in that the transformers I have are
> from an R23 and have tapped coils in the first and IF second cans.
> Was wondering if it would be better to modify the connections or use the
> taps as they did in the R23.
>
> Tnx and 73,
>
> Tony
>
>
> --- On Thu, 12/11/08, hbrnut at suddenlink.net <hbrnut at suddenlink.net> wrote:
>
> > From: hbrnut at suddenlink.net <hbrnut at suddenlink.net>
> > Subject: Re: [HBR] 85Khz IF Transf.
> > To: "HBR Receiver List" <hbr at mailman.qth.net>
> > Date: Thursday, December 11, 2008, 8:41 AM
> > I used these in my first HBR (photos are on the HBR Web
> > Site). In mine, the transformers had 220 pF fixed capacitors
> > across the coils. By changing them to 110 pF, I brought them
> > up to 100 kc. They work very well. One small pitfall is that
> > the tuning range of the trimmer capacitors used in them is
> > very limit.
> >
> > 73,
> > Darrell, WA5VGO
> > ************************************
> > Visit the HBR Receiver Web Site with over 100 pictures of
> > receivers and
> > construction notes...... via http://www.qsl.net/k5bcq/
> > there is also a mirror (faster response)at
> > http://k5bcq.edebris.com/
> >
> >
> > Retrieve reflector archived data via
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>
>
>
> ************************************
> Visit the HBR Receiver Web Site with over 100 pictures of receivers and
> construction notes...... via http://www.qsl.net/k5bcq/
> there is also a mirror (faster response)at http://k5bcq.edebris.com/
>
>
> Retrieve reflector archived data via
> http://mailman.qth.net/mailman/listinfo/hbr
>
>
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