<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=windows-1252" http-equiv=Content-Type> <META name=GENERATOR content="MSHTML 8.00.6001.19019"> <STYLE></STYLE> </HEAD> <BODY dir=ltr bgColor=#ffffff> <DIV><FONT size=2 face=Arial>Thanks Larry, your explanation certainly seems to fit.  The bloke who brought it to me purchased at a garage sale, and has had it for years. At last he got round to asking me, and I had no idea!!</FONT></DIV> <DIV><FONT size=2 face=Arial>I will send on your suggestion, thanks again.</FONT></DIV> <DIV><FONT size=2 face=Arial>David Lawson OZ</FONT></DIV> <DIV> </DIV> <DIV>----- Original Message ----- </DIV> <BLOCKQUOTE style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px" dir=ltr> <DIV style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B> <A title=larryf@pacifier.com href="mailto:larryf@pacifier.com">Larry Fisher RPT</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A title=pianotech@ptg.org href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, March 02, 2011 2:31 AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> [pianotech] Unusual Tuning fork (David Lawson)</DIV> <DIV><BR></DIV> <DIV dir=ltr> <DIV style="FONT-FAMILY: 'Calibri'; COLOR: #000000; FONT-SIZE: 12pt"> <DIV>Hello David,</DIV> <DIV> </DIV> <DIV>How’s things going for ya??</DIV> <DIV> </DIV> <DIV>My first thought is it’s a frequency standard for radio work.  It’s not big enough for 100 cps so I don’t know what that number is.  I’ll forward this over to my brother who at the age of 12 built his own ham radio transmitter.  </DIV> <DIV> </DIV> <DIV>In the olde days you had to “align” receivers by tuning the “IF cans” so that they’d operate at their optimum.  A frequency standard was used to accomplish this.  Station WWV was the source for this.  At various places on the ham radio dial you could find this station located just outside Wellington, CO.  Every minute they’d announce the geophysically correct time.  A tone would pulse every second for 50 seconds and then the announcement would take 10 seconds to complete.  After many hours of working with this radio source in my youth, I can still remember the announcement.</DIV> <DIV> </DIV> <DIV>“This is WWV, Fort Collins, Colorado. (small pause) The next tone begins at (short pause) X hours, X minutes.”  Then there’d be another short pause and the first tone would be slightly longer than the others.  At 30 seconds there was a double click I think.</DIV> <DIV> </DIV> <DIV>The “metric” version of this was CHU CANADA, announced in French.</DIV> <DIV> </DIV> <DIV>Regardless, it looks like someone needed an electromechanical frequency standard.  20 years ago they could have produced a solid state version of this but I guess there were some stability issues to deal with.</DIV> <DIV> </DIV> <DIV>Lar</DIV> <DIV> </DIV> <DIV> </DIV></DIV></DIV></BLOCKQUOTE></BODY></HTML>