Hi Jim; I understand arcing at standard Temp. and pressure. I thought that the reduction of media would produce an increase of voltage Vs. distance (vacuum relays and Caps.)
I'm missing something here. pete kn6bi -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED] Sent: Thursday, August 03, 2006 5:20 PM To: Elecraft@mailman.qth.net Subject: Re: [Elecraft] Multimeter Altitude Limits In our high altitude ballooning program at LSU (>120,000 feet) it's necessary to be very careful about sharp edges and corners in circuits of even modest voltages. Vacuum chamber testing is an essential part of the payload development. Our student payload had a Geiger-Muller tube, and that's a couple hundred volts, so they had to be sure to test in the chamber. Interestingly... 6500 ft is 1981 meters, so I speculate a conversation like.. Pointy Haired Boss: We need an altitude limit because of HV arcing, what do think it should be? Alice: Oh, couple thousand meters or so should be safe enough. Pointy Haired Boss: OK, tell marketing. Alice: Fine, but remember we're selling it in the USA. Pointy Haired Boss: Not to worry, ad copy writers will take care of conversion. I recall a wireless device whose range was specified on the package to be "up to 328 feet." Amazing how they knew it would work at 327 but not at 329. Of course what was meant was that the range was about 100 meters. :^)) 73 Jim N5IB _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com __________ NOD32 1.1691 (20060803) Information __________ This message was checked by NOD32 antivirus system. http://www.eset.com _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
