[Lowfer] Preamp question

[Jay Rusgrove]

Mitch

Roger on all.

Just curious...what are the big NDB and AM broadcast stations up your way? Since
I can now listen to the NDB and broadcast bands while the VD "gravel grinder" is
running I'll keep an eye on propagation over our route.

Jay

Mitch Powell wrote:

> >
> > The transformer should have 30 turns of bifilar wound on it. Connect one
> > wire from one end of the pair to the opposite wire at the other end of
> > the winding.
>
> That's exactly what I did - I assumed bifilar was correct. Thanks for the
> confirmation.
>
> If the winding is correct and the resistor values are
> > correct the feedback will establish the gain at 20 dB. Over the years
> > we've built about 2000 of these amplifiers and I've never seen the gain
> > stray more than a dB from the 20 dB mark.
>
> I will do a more detailed check after I box things up and tighten up the
> leads.
>
>
>  Since the preamplifier doesn't overload (I
> > can only speak for my location) there really is no reason to tune it to
> > resonance anyway - right?
>
> Yes - I am using the pre-existing tuned loop - and it's been raining for
> 1-1/2 days now so can't get outside and "un-tune" it. Looks like good wx
> tomorrow so will throw the capacitors away !.
>
> Thanks again
>
> 73
>
> Mitch
>
> P.S. Don't let Bill know that I have a 7 ft octoloop , a KI0LE open frame
> with remote tuning, as well as these two antennae. How many permutations can
> we do with that ?  <grin>
>
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