On Thu, 14 Feb 2013 22:31:44 -0500, "Michael A. Terrell"
wrote:
Huh? I haven't seen any of the external 12V power supplies that have
failed. I think I've gone through about 8 of them so far, mostly used
on a previous generation of weather stations. I've been tempted to
see what range of voltage the SX260 will operate. I want to put it on
a storage battery and charger system, which means anything between
11.0 and 16.0VDC. Have you ever tried it? (I don't want to risk
blowing up my last remaining SX260 machine).
Why not use a switching converter that boosts then bucks the voltage
so you can run it anywhere you want.
I could use a 12v to 12v DC to DC converter to deal with the input
range. However, these weather stations are mostly on mountain top
radio sites, where the switching noise would not be welcome. I've had
problems with this in the past and would like to avoid it. We have a
perfectly good 12V battery based system running the stuff that will
run on 12VDC, which is most everything these days. I just wanted to
add the SX260 to the 12V battery bus. The only problem is not knowing
the range of voltages it will tolerate. I guess I'll have to
sacrifice an SX260 or SX280 and see what blows up. (I've failed to
find schematics).
I'm currently working on a 12 to
90 volt converter design for run antique radios from a Lead acid, NiMh
or NiCad battery pack in the 8 to 16 volt range.
Well, there are battery eliminators for such radios, but they mostly
run on 117VAC.
I had fun finding
reasonably priced feedthrough caps, and will have to hand wind the
transformers. I need to keep the EMI down so it won't bother the radio
on weak signals.
Yeah, that's the killer. I have the stock 12V to 117VAC converter
that bolts onto the back of my Wavetek 3000B service monitor. Running
on 12VDC, it generates enough noise to make the receiver in the
service monitor useless for anything except very strong signals.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558