At 10:54 AM 2/18/2011, Bob Bruninga wrote: > > Is there a Amsat BB favorite between switching and linear [power >supplies]? > >I won't speak to noise, which is the only potential issue with switching >power supplies, but other than that, I am writing an article for QST that >points out how the world of power and emergency power has changed >drastically over the last decades. Entirely due to switching power supplies >and regulators: > >PROS: >1) A 90% reduction in size and weight >2) Laptop supplies that can supply 12v at 5 to 10 amps >3) Universal inputs 115V to 240V AC >4) * also run on 150 to 330 VDC >5) Hybrids and Electric Vehicles have Kilowatts of 150 to 330 VDC available >6) Home grid-tie solar has Kilowatts of high voltage DC available >7) 12VDC to 120VAC inverters are now sine and modified sine at 90%+ >efficiency >8) * These internally run on 200 VDC or so. Easy to run great distances on >small wire if you run them directly on HV DC derived from your Hybrid or >Solar. > >CONS: with today's litigious society and general ignorance (compared to the >vacuum tube days when even cub-scouts built 2 tube radios with High >Voltage), it is doubtful that QST will publish the article. They have >rejected it before, but I keep whittling away at the details. > >Bottom line, is that high efficiency high voltage DC is everywhere and >because everything runs on switching power supplies that run internally on >HV DC and regulators that accept a wide range of input, then HV DC could be >the new universal power source. > >Problem is, Hybrid and EV MFR's are not going to provide access to HV DC >willingly due to safety an liability issues. Same for Solar installers.... >Same for QST. > >But you can get some of what I am writing about on this page: >http://aprs.org/FD-Prius-Power.html >http://aprs.org/alternative-energy.html > >For example, buried in a Camry Hybrid is a nice compact stand-alone 14 volt >100 AMP DC/DC supply. Input can be 200 to 350 volts DC (which you can get >from 120V or 240VAC with just some diodes).. Problem is, it is bolted to >the $1000 salvage battery and the salvage guys won't sell it separately. > >The Prius 100amp 14v supply is integrated into the huge drivetrain inverter >and inseparable from that $3000 unit (salvage cost). > >As we electrify transportation and anyone with good sun goes solar, HV DC >will be something Hams will be getting used to again. > >Bob, Wb4APR > >_______________________________________________ >Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. >Not an AMSAT-NA member? Join now to support the amateur satellite program! >Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I am rebuilding my 4.2kV PS for the 2m-8877. Does that qualify? QST still publishes high-power tube amplifier designs in their handbook. What's 150-250v amongst friends? Of course HV DC can badly burn or Kill you. I was 14 years old when working on my DX-35 with 850vdc on the 6146 plate. I agree that many hams these days aren't not trained to handle high-voltage with all the 12vdc solid-state electronics available. But QRO sspa are running at 50vdc and higher. There are rules for safe work on HV...time to review them. 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com EME: 144-1.4kw*, 432-100w, 1296-testing*, 3400-winter? DUBUS Magazine USA Rep dubus...@hotmail.com ====================================== *temp not in service _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
