Older wall warts are linear. If you're smart enough to have saved them,
there's a good chance you won't have buy anything. Simply select one
with the matching voltage and rated for the needed current, cut the
cables to both old and new warts, splice the old wart to the connector
that mates with the unit you need to power.
Older warts are often available at second hand stores and flea markets.
$1 is the going rate. In general, linear warts are much heavier than
SMPS units, so that's a good first check. A better one is to plug it
into AC and hold a portable radio next to it tuned somewhere near 2 MHz
(like the top of the AM BC band). If you hear hash, it's a switcher. If
you don't., 99% chance that it's linear.
All of this is described in http://k9yc.com/KillingReceiveNoise.pdf
73, Jim K9YC
On 11/20/2017 1:17 PM, Joe Subich, W4TV wrote:
All Electroncs (www.allelectronics.com) has analog wall warts of various
voltage/current capability depending on what is available in surplus at
any given time. One may not even need regulated voltage as many devices
contain internal regulators ...
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]
