[time-nuts] time-nuts] Digital Clock kit - no Integrated circuits!

[Morris Odell]

From: Steve Rooke <sar10538 at gmail.com>
Subject: Re: [time-nuts] Digital Clock kit - no Integrated circuits!
To: Discussion of precise time and frequency measurement
	<time-nuts at febo.com>

2010/1/9 Tom Clifton <kc0vsj at yahoo.com>:
> http://transistorclock.com/? has a very interesting (though a bit
expensive) kit for sale.??A 10" x 11" circuit board sporting nearly 200
transistors and 600 diodes to drive six seven-segment displays.? Suitable
for framing...? As delivered runs on 60hz but there is a note about
conversion to 50hz mains.? You can buy a? bare board, just the components or
a full kit.
>
> You must see it to believe it!

> Bah humbug! Stupid modern day design, it'll never be any good, you
> need to use valves to make real gear :-)

Not only do I have a 5245M but no less than TWO HP 524 counters. One's a "B"
with 88 valves, 6 neon columns and 2 meters for the last 2 digits, the other
is a "D" with a similar number of valves and, yes, 8 Nixies. They are driven
5245 style with neons & photoconductors.

When the 2 coutersaurii are going and their output waveforms are being
compared on the Tek 555 scoposaurus there are about 300 valves glowing away
and about 2.5 kW being dissipated. Definitely not to be done during the
Australian summer - 39C here today.

Morris