From: Brooke Clarke <[EMAIL PROTECTED]> Subject: Re: [time-nuts] 75Z vs 50Z for GPS receivers Date: Mon, 05 Feb 2007 20:20:53 -0800 Message-ID: <[EMAIL PROTECTED]>
> Hi Didiere: > > There's also an app note at Linear Technology for making pulses so fast > they are used to calibrate sampling scopes. > > Some years ago I made a very simple circuit that pulses a LED with many > amps (very short time) based on a transistor going into avalanche. You can actually use a 1N4148 for below 1 ns risetimes. NBS/NIST used a 1N4148 as a 100 MHz to 700 MHz stepup in a ionic measurement setup GPS receiver design so that they fed 100 MHz up to the antenna, stepped it up to 700 MHz and used that into the mixdown step in the antenna assembly. I think their use of a 1N4148 was a twist of a culprit just to show it is the methods and not the tools which is important. :) This design is burried somewhere in the NIST archive. Cheers, Magnus _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
