[MRCA] SCR-274-N receiver bandwidth spec

[J. Forster]

If the washer is metalic, even brass or aluminum, it will decrease the
mutual inductance between the coils, thus narrowing the 'rabbit ears'
response curve or narrowing the BW.

-John

===============


> Gentlemen,
>
> Continuimg with my ARC-5/SCR-274-N receiver IF coil mod investigation, I
> just completed yet another coil set, this one from an ARC-5/R-26.  In
> doing so, I find yet another mechanical set-up in these coils.  This one
> has the long brass screw (up from the bottom) and threading into the
> phenolic spacer bar (vice using a nut).  All else is the same as other
> coil sets and I find that coils sets are, so far,  interchangeable.  The
> question for today is what is the original published (sic) receiver
> bandwidth of this receiver?  I'd like to know what the starting point
> should be, even though I'll be measuring unmodified and modified sets.
> At this point, I can again say that there /is/ a detectable improvement
> in selectivity.  What remains is to quantify things and, as we speak,
> I'm proceeding with the procurement of a suitable sweeper.
>
> Another point of possible interest is the fact that in each and every
> coil set there appears a 1/2" disk "shield" positioned between the upper
> and lower coil bobbins.  Could this be what others have spoken of as a
> method of providing electrical separation (read: increased selectivity)
> between these coils?  If so, then someone back then was thinking.........
>
> Regards    Jeep - K3HVG
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