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Old 18th Nov 2020, 12:34 am   #16
DMcMahon
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Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,604
Default Re: Uher CR 240 adjustments - operating point and hub tension

Set up my CR 240 6.6V setting for operating voltage to the left edge of the green field on the left VU meter, it was way off around -10dB, had to adjust the R 1001 trimmer fully clockwise to just about get it to reach the left edge.

Seriously struggled to capture even a half reasonable scope picture. On Play AC coupled, signal very spikey like differentiated pulses. On DC coupled sort of a square wave with quite rounded leading edge. On FFD and RWD the signal was somewhat better.

No improvement to signal with increased operating voltage.

Did not attempt any hall effect sensor/magnet adjustment.

With numerous attempts at different sections of the tape, Play never stopped until it reached the end.
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