>>>"Jim and Kate Belt" said:
>
> Hi All:
> Recently I put a Logikey K3 keyer into operation. The manual says not to use
> wall type transformers since anything over 14 volts DC is apt to fry the
> unit. I had planned on using the MFJ 1313B twelve volt transformer. When I
> checked it it registered 18 volts. When I called MFJ they said it would
> deliver 12 volts under load. Then I took a variable Radio Shack transformer
> that delivers between 6 and 12 volts DC. At the 12 volt setting it measured
> 12 volts DC. It never would have occured to me to question the advertised or
> assigned ratings. A word to the wise.
The key is (usually) looking at the wording on the wall-wart. If it says 12VDC
at 200mA it is likely unregulated. Checking it open circuit as you did is a
definite giveaway.
--
73 de KK1L...ron (rrossi@btv.ibm.com) <><
QTH: Swanton, Vermont
My page: http://www.together.net/~larossi/kk1l.html
My wife's page: http://www.together.net/~larossi
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