491: Power sw broken A 10 turn pot for the fine RF center freq is not working 531A: Problem: Trace on oscilloscope only 4 cm long, starting 3 cm from left edge of screen. Cause: connector on left horizontal deflection plate made poor contact. After cleaning and fitting connector on pin, scope works great 585A: When connected to 230VAC, 120V fan intermittant shorting half the windings, replaced fan
Problem: Normal sweep only 4cm, magnified sweep only 10cm. Distortion of sweep amplitude. Sweep larger beginning, and shrinks about 1/2cm at end.
Solution: A wire going from the horizontal sweep terminal board to the sweep magnifier adjustment board (mounted to the carry bar) was broken. This broken wire caused caused the RH horizontal sweep signal to be stuck somewhere between 300 and 400v. As a result, all of the sweep action was being done by the LH sweep amplifiers.
Cause: At some point in the life of the scope, the carry bar either was removed without first disconnecting the sweep magnifier gain board, or the carry bar screws fell out, and the bar lifted up when the scope was lifted by the carrying handles. This stretched the wire to the breaking point.
Relay not engaging. Remove contacts cover. Unscrew pivot holder,
free up pivot and lub and reassemble. voila.
Back to Main