Re: Strobe circle



In article <43fccf14.4993203@xxxxxxxxxxxxxxxx>,
Willie K. Yee, MD <wkyee@xxxxxxxxxxx> wrote:
Anyone know where I can download a graphic for a 33 1/3 strobe circle
for a turntable?


Here is a postscript file that will print a strobe disc. Save it to a
file and make sure the %! is on the first line, then print to any ps
printer.

--cut here--
%!
%
% Turntable strobe disc - 33-1/3 and 45 RPM @ 60 Hz
%
% A. W. Rogers, 08/30/93
%
% Instructions:
%
% print (preferably on heavy stock) and cut out (including spindle hole)
% place on turntable under neon or fluorescent light
% start turntable and adjust speed until tics are stationary

/ticwidth 1.5 def % width of tics
/ticlength 20 def % length of tics
/r33 200 def % radius - 33-1/3 RPM
/t33 108 def % number of tics - 33-1/3 RPM
/r45 150 def % radius - 45 RPM
/t45 80 def % number of tics - 45 RPM
/r 250 def % radius of outer circle

/Helvetica findfont 12 scalefont setfont
50 100 moveto
(Outer ring: 33-1/3 RPM @ 60Hz) show
50 85 moveto
(Inner ring: 45 RPM @ 60Hz) show

306 396 translate % center of page
newpath
0.1 setlinewidth
ticlength 2 div neg 0 moveto % centering mark
ticlength 0 rlineto
0 ticlength 2 div neg moveto
0 ticlength rlineto
stroke
0 0 r 0 360 arc stroke % outer circle

ticwidth setlinewidth % outer (33-1/3 RPM) ring
/angle 360 t33 div def
1 1 t33 {
gsave
angle mul rotate
0 r33 moveto
0 ticlength rlineto
stroke
grestore
} for

/angle 360 t45 div def % inner (45 RPM) ring
1 1 t45 {
gsave
angle mul rotate
0 r45 moveto
0 ticlength rlineto
stroke
grestore
} for
showpage

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
.