Robert Atkinson wrote: > Hi, > Have a look at, > < http://www.wenzel.com/pdffiles/diodedbl.pdf > > Also http://www.wenzel.com/documents/hints.htm indicates that the NIST > design uses JFET's but I can't find any more details. > > Robert G8RPI. > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Christopher Hoover > Sent: 26 October 2006 07:14 > To: time-nuts@febo.com > Subject: [time-nuts] 5 MHz Frequency Doubler > > > Hey 'nuts, > > I'm looking for a good design for a 5 MHz frequency doubler. > > The Wenzel Blue Tops HF doubler is said to be based on a low phase > noise, public-domain NIST design: > > > <http://www.bluetops.com/Modules/lnhd.htm> > http://www.bluetops.com/Modules/lnhd.htm > > The LNHD is a fixed-frequency HF doubler based on a public-domain design > developed by the National Institute of Standards and Technology (NIST > <http://www.boulder.nist.gov/timefreq/> ) for superlative phase noise > performance. > > > Can anyone point me at a this design? I haven't had any luck finding it > on the web. > > I'm open to suggestions on other doubler designs, as well. > > -ch > > > _______________________________________________ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > -------------------------------------------------------- > Any opinions expressed in this email are those of the individual and not > necessarily Genetix Ltd (Genetix) or any company associated with it. This > email and any files transmitted with it are confidential and solely for the > use of the intended recipient. If you are not the intended recipient or the > person responsible for delivering to the intended recipient, be advised that > you have received this email in error and that any use is strictly > prohibited. If you have received this email in error please notify Genetix by > telephone on +44 (0)1425 624600. > > > The unauthorised use, disclosure, copying or alteration of this message is > strictly forbidden. This mail and any attachments have been scanned for > viruses prior to leaving Genetix network. Genetix will not be liable for > direct, special, indirect or consequential damages as a result of any virus > being passed on, or arising from alteration of the contents of this message > by a third party. > > _______________________________________________ > time-nuts mailing list > time-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > The design is probably a pair of low noise n channel JFETs configured as a push push doubler. Inputs driven in antiphase so that each FET conducts ffor opposite 1/2 cycles with the 2 FET drains connected in parallel. A bypassed trimpot connected between the FET sources being used to compensate for FET mismatch. The low frequency design probably uses a common source design whilst the VHF version employs a pair of common gate devices. An RF transformer connected between the the common drain and the positive is used to drive the load.
Bruce _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
