KX3 and switching power supplies

[wayne burdick]

The KX3 owner's manual isn't quite clear regarding switching power  
supplies. Yes, many of them are very noisy, especially the miniature  
variety with no shielding. But well-designed switchers with good  
shielding and filtering are just fine. This includes a lot of the  
larger bench supplies in use by many hams.

Today I picked up a Radio Shack 22-507 switching supply (in the $60  
range), which Eric (WA6HHQ) has been using with his KX3. It has a  
metal enclosure and is pretty rugged. Even though it's larger than the  
miniature types, it's still small enough to take with you when you'll  
have AC power available. I swept all bands and didn't hear any of that  
drifty hash that I've heard with poorly designed switchers.

73,
Wayne
N6KR


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[erehm]

Beware buying a used Radio Shack 22-507 supply:

July 2, 2008
RadioShack Recalls Power Supplies Due to Electrocution and Fire Hazards
WASHINGTON, D.C. - The U.S. Consumer Product Safety Commission, in cooperation with the firm named below, today announced a voluntary recall of the following consumer product. Consumers should stop using recalled products immediately unless otherwise instructed. It is illegal to resell or attempt to resell a recalled consumer product.
...

Description: The recall involves RadioShack 13.8V DC Power Supplies, catalog numbers 22-507 and 22-508 with date codes from 08A04 through 01A08. Date code format is MMAYY where MM is the month and YY is the year. The catalog number and date code are located on the back of the power supply. Power Supplies with a green dot on the product and the product’s packaging have already been repaired and are not included in the recall.

http://www.cpsc.gov/cpscpub/prerel/prhtml08/08319.html

/eric,kj7ae