18 Feb
2007
18 Feb
'07
2:03 p.m.
On 18 Feb 2007 at 16:41, Bob Bradlee wrote:
I remember commenting about the lightbulbs flickering
in the NY subway and my dad tellling me that the
subway operated on 25 cycle. this was close to 50 years ago. I asume it has been upgraded
by now.
You should have seen mercury-vapor lamps operating off of 25Hz. The
electricians would drive them from all three mains phases, so the
lighting on the ground didn't look too bad, but if you glanced up
toward the roof, it was very disturbing.
Cheers,
Chuck