24 Jun
2013
24 Jun
'13
9:53 p.m.
On Mon, 24 Jun 2013, Jim Brain wrote:
On 6/24/2013 10:00 PM, dwight elvey wrote:
If you are considering a full-range switch-mode PSU (100-240V), it might
indeed be best to synthesize 60Hz using modern parts so that the same PSUs
can be used in countries that supply mains power at 50Hz.
If the 9VAC is only used to produce the +volts
for the serial
chips, there is no real reason to use AC. A +15VDC would most
likely work fine.
One could use a cheap small switcher.
Dwight
As previously noted in my original post, the TOD clock uses the 50/60 hz to
update the TOD time. Without it on the 9VAC lines, the TOD clock will not
run. Some apps will not function as a result.