If the counter has not been taken, I want it!!! John WA4WDL Yorktown, VA 23693
----- Original Message ----- From: "Bill Hawkins" <[EMAIL PROTECTED]> To: "Discussion of precise time and frequency measurement" <[email protected]> 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/ > timer. > > 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 > [EMAIL PROTECTED] > > > _______________________________________________ > time-nuts mailing list > [email protected] > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
