[time-nuts] time-nuts Digest, Vol 22, Issue 20
jmfranke at cox.net
Thu May 18 08:21:40 EDT 2006
If the counter has not been taken, I want it!!!
Yorktown, VA 23693
----- Original Message -----
From: "Bill Hawkins" <bill at iaxs.net>
To: "Discussion of precise time and frequency measurement"
<time-nuts at febo.com>
Sent: Thursday, May 18, 2006 1:26 AM
Subject: Re: [time-nuts] time-nuts Digest, Vol 22, Issue 20
>> Looking to get good colour photos of some of these
>> older HP counters (and similar offerings from other
>> manufacturers) in the pre/early Nixie etc period.
> Here's an opportunity to own an HP 522B for $25, including
> shipping in the US. The unit has 5 decades of ten vertical
> neon indicators each. It works. Yes, it's a 100KC counter/
> I got it from a blasting cap plant where I worked in the
> early sixties. It was used to measure the delay time of
> time delayed blasting caps, used to remove successive
> layers of rock from a quarry or tunnel wall. The start
> pulse came from the blasting machine, attenuated. The
> stop circuit was normally closed by a pencil lead held
> in alligator clips for quick replacement. The cap broke
> the lead when it fired. For a while, it was used in
> Pinewood Derby races. It has never been exposed to weather
> and looks new inside.
> Bill Hawkins
> bill at iaxs.net
> time-nuts mailing list
> time-nuts at febo.com
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