Crystal ovens have been used since at least 1940. Probably longer. ----- Original Message ----- From: "KPL" To: "Microcontroller discussion list - Public." Sent: Thursday, May 24, 2007 3:55 PM Subject: Re: [EE]: Digital voltmeter from 1960 > It was made in ussr. I do not have it nearby now, may be I can > photograph it if I will remember. > Actually almost all equipment that is affordable for amateurs here, is > old russian stuff. But quite often those are good tools. > > Btw, is anybody using this technique nowadays, like heated frequency > sources? It would be much easier now, with peltier elements and some > kind of integral regulator. I have seen audio amplifier IC used for > this regulator somewhere. > > > On 5/24/07, Rich wrote: >> Who is the manufacturer? >> ----- Original Message ----- >> >> > Actually I have old digital frequency counter from 70-ties, which is >> > still working fine and is even getting used sometimes, since my >> > pic-based counter is not finished:) >> > Nice tool, built completely on discrete components, no IC's. Nixie >> > indicators, even some kind of connector for remote control. >> > A bit frightening to see _that_ amount of cards inside, full of diodes >> > and transistors. >> > There is temperature controlled heated, insulated frequency source for >> > better stability. >> > > > -- > KPL > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist