[HBR] 6SN7 infinite-impedance upgrade for HBR-14

[Tim Shoppa]

Kees K5BCQ wrote:

> I'd really like to answer your question, but I
> don't know and I can't find it in the HBR-14
> material.

Evidently this upgrade is more closely associated
with the HBR-16 material. I don't know if in the
original HBR-16 article or one of the follow-ons,
or maybe a "hints and kinks" from the same
timeframe, or ???

I would guess, because the mod article evidently
suggests a 6SN7 rather than a 12AU7, that the
mod was written by someone who used parts
at hand rather than parts that match :-).

I'm going to proceed under the assumption that
the modification is very very similar to the HBR-16 stages.

I write all this as a "new owner" of a HBR-14 with 6SN7
and 6BE6 in it!

Tim.