Steve Baker (steve++at++mred.bgm.link.com)
Tue, 12 Nov 96 07:43:30 -0500
> the last time I checked (and already had my foot placed
> firmly in my mouth concerning the added frame time for a
> Euro-trainer), the RE machines do not (that is, do NOT)
> work at 50 Hz - the video rate is synthesized and not
> driven by the AC line frequency
You certainly *can* run your RE2 or iR at either 50 or 60 Hz
with either 50 or 60Hz AC line frequency.
We have RE2-based simulators in service with Burlington Northern
Railroad that have 50Hz video and 60Hz AC power rates - and we
have taken 60Hz video systems and run them in countries with
50Hz AC power.
The deal is that when the room lights are running at one rate
and the video is running at another rate close to it, you
get beat frequencies that can be very upsetting. If your
simulation is run in a darkened room, (as most of ours are)
then there is no problem with mixing the power and video rates.
With 60Hz lighting and 50Hz video, you get 10Hz flicker which
is pretty nasty if the room lights are bright.
Performer is still limited to an exact sub-multiple of the
video rate - so with 50Hz video, it has to be run at 50, 25,
12.5Hz, etc frame rates instead of the usual 60, 30, 15Hz.
Similar arguments apply to 72Hz and higher video rates - but
the higher the frame rate - the less noticable the frame-rate-
mismatch-flicker.
Steve Baker 817-619-1361 (Vox-Lab)
Hughes Training Inc. 817-619-8776 (Vox-Office/Vox-Mail)
2200 Arlington Downs Road 817-619-4028 (Fax)
Arlington, Texas. TX 76005-6171 Steve++at++MrEd.bgm.link.com (eMail)
http://www.hti.com (external) http://MrEd.bgm.link.com/staff/steve (intranet)
http://web2.airmail.net/sjbaker1 (external)
=======================================================================
List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/
Submissions: info-performer++at++sgi.com
Admin. requests: info-performer-request++at++sgi.com
This archive was generated by hypermail 2.0b2 on Mon Aug 10 1998 - 17:53:56 PDT