Chris Starting with 3.4 W used by the Tbolt my battery version burns 4.4 W. Using a switcher do generate 7 V 4.8 W and running the 7805 directly from 14.5 V 6.2.W. I use like you an IC temp sensor, two stage op amp driving a fan holding the backplate temp constant and total power goes up to 7.6 W since the oven has to work harder. T bolt, switchers and all regulators are on the other side of the 3/32" Alu plate. The AC switcher is not included in the power numbers. but is also on the plate. Plate is held at 40 C. I am looking for a way to more closely couple the Tbolt circuit board to the back plate and am looking for the material switchers use between semiconductor and cooling plate Any one know where I can buy it in sheet form? Bert Kehren
-----Original Message----- From: Chris Albertson <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]> Sent: Sun, Aug 26, 2012 12:31 pm Subject: Re: [time-nuts] newbie question Thunderbolt supply On Sun, Aug 26, 2012 at 3:46 AM, <[email protected]> wrote: > Having played with several solutions I found the best is a 12 V 1 A switcher with the output voltage increased to 15 V, check the capacitors and if necessary replace with 25 V. I laid out a PC board that has a TC7662A inverter followed by a 79L12. Also on the board is a 7812 followed by a 7805. Putting them in series gives me good thermal distribution. .... ne of the advantages of generating waste heat like that is that you can ut the heat to good use. I build a temperature controlled fan. It is ery simple a temperature sensor IC connects to an opamp that drives a ower transistor that drives a 12V fan. As for the power supply. I used a filter that does not drop any volts and can't see any RF on the DC using my old 365 Tek scope or by using a more ensitive RF power meter. hris Albertson edondo Beach, California ______________________________________________ ime-nuts mailing list -- [email protected] o unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts nd follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
