*20
/X                           X                           X
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/THIS IS THE STANDARD 16-LINE CALIBRATION BLOCK. IT"S USED
/DURING BOTH CALIBRATION AND VERIFICATION. THE SOURCE IS
/SAVED ON FREE DIAL-TAPE BLOCKS 271 AND 272, AND ALSO AS
/SOURCE FILE "CALBLK" ON THE DIAL TAPE. CAN YOU, THE
/READER, READ THIS THROUGH THE SMALL WINDOW? THE WINDOW
/SHOULD APPEAR JUST WHERE YOU"RE LOOKING! DOES IT? TRY
/ LOOKING ALL AROUND THIS PAGE, TOP AND BOTTOM, LEFT AND
/RIGHT. TRY TO NOTICE THE PLACES WHERE THE WINDOW IS NOT 
/PLACED PROPERLY. HOW MANY CHARACTERS DO YOU SEE IN THE 
/WINDOW AT ANY ONE TIME? DO THEY SEEM SLIGHTLY OFF-CENTER
/ TO YOU? IF SO, WHICH WAY? THERE ARE ACTUALLY 5 CHAR-
/ACTERS PER WINDOW, HOPEFULLY CENTERED EXACTLY! IS IT
/HARD TO READ WITH SUCH A SMALL WINDOW? WHY DO YOU THINK 
/THAT IS? YOU"LL BE TRYING TO READ PASSAGES WITH ALL
/DIFFERENT SIZES OF WINDOWS. FEEL FREE TO REST ANY TIME
/YOUR EYES FEEL TIRED. THERE"S PLENTY OF TIME!