Norman,

If the WRAP is rated from 7-18V, I would suggest you use something in the 
7.5-9v range as the higher you go with this voltage the more heat your WRAP 
will have to dissipate!  In this case, lower is better. :o)

Roy...

>
>You could be right.  Interestingly, the technical spec calls for +12VDC at 
>~400ma in active state, and recommends a range of 7-18V.  BTW, it also 
>claims operational temperature range of 0-50C.  It almost certainly didn't 
>get over 35C in my attic.  OTOH, if the PS is marginal, then all bets are 
>off.  The one that PCEngines sells is a hefty 18V @ 800ma, and since the 
>price is good, I guess I'll go for that.
>