[HBR] HBR 13C

[Walt Hutchens]

> I was looking at the Jackson Brothers drive and dial. Any thoughts. Don't
> mine buying a new one.

I think the two-speed J-B drive 'makes' the modern HBR project: It's
no more difficult to use than the National (etc.) dials of the
original; can, indeed be compatible with those dials; and gives you a
tuning rate that allows receiving SSB without difficulty.

By all means get a new one. Only rarely would you find a used one that
was tight enough to work well. While they have a pretty long life, the
sets on which these were installed were often used over decades by
more than one owner: By the time they became 'parts,' the dial drive
was most often worn out.

> Any reason I can't use a tube power supply?

No reason at all except for significantly increased heat generation.
And even that doesn't matter if you build the power supply on a
separate chassis, external to the HBR enclosure.

It's not just the rectifier heat that's removed from the cabinet with
a separate power supply; you also get rid of the power transformer
dissipation which can be ~half of the total power consumption of the
set.  Small power transformers are not very efficient!

Walt
KJ4KV