[HBR] Regenerative communications receiver

[Brian Burns]

Hello Martin,

How about substituting them for "peanut tubes" ? I'm planning to build a
battery regen from the Feb.1940 issue of QST that specifies 1T4's, for
instance.

I would expect that power requirements would be less, and high frequency
performance better too, but what do I know (;->)...

Cheers,

Brian

On Tue, Jun 2, 2015 at 3:00 PM, Martin Marris <mmarris at notecraft.com> wrote:

> >>How do you find working with subminiatures? They look awfully small and
> fragile.<<
>
> It might seem that way, but it's the opposite. They were used at the
> tail-end of the tube era in high-reliability situations such as missile
> guidance systems (inside missile nose cones) or high-altitude aircraft
> gear.
> You can subject them to the sort of vibration and other stresses that
> larger
> tubes cannot handle. See, for instance,
> http://frank.pocnet.net/other/Sylvania/GuidedMissileTubes.pdf (this may be
> slow to load).
>
> When using them in homebrew gear, you can wire them into the circuit much
> like transistors because they have long, flexible leads. The 1AD4s I am
> using are cheap (about $2 each from some suppliers) and abundantly
> available.
>
> I took a break during writing this email to put a 1AD4 on the hard-tile
> kitchen floor, and then stepped on it, putting my entire weight on the
> tube.
> Nothing happened. I've never tried to do that with a conventional, larger
> tube -- maybe it would survive too, but I'm not so sure.
>
> A sub-set of these tubes was designated as "reliable" by the U.S. military,
> meaning, actually, almost indestructible. The Raytheon catalogue for
> "reliable" tubes has pages and pages of the "torture tests" that these
> tubes
> went through before being certified as "reliable."
>
> Strange but true; and quickly eclipsed by solid-state.
>
> Martin
>
>
> ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>