BBK BX900U, Service Manual

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SAFETY CHECKS
Important Note!!! Do the following safety checks after servicing this unit.
1. Remove all the externally connected test equipment and wires before testing the unit.
2. Use the safety test circuit as shown below.
3. Plug the power cord or unit to be tested into the test receptacle.
4. Switch the unit being tested to ON or PLAY.
5. Connect external jack/terminal contact VTVM across a 1k resistor in the test circuit. Set the meter to
a high (150V AC) scale to avoid meter damage and then touch the points with the test probe.
If the meter reading indicates less than 3 volts on all test points, set the meter to a low (3V AC) scale
and repeat the test.
6. Any reading greater than 0.2 volt indicates a potential shock hazard. If this occurs, determine the
cause of the leakage, correct the problem, and repeat the safety test.
ALIGNMENT AND ADJUSTMENT
SERVICE ADJUSTMENT
Lubrication
The mechanical parts are factory coated with a thin coat of light grease and should not require further
lubrication. If a light grease is applied, be careful not to get any grease on the play/record head or erase
head, hubs, pulleys, tapes reels, drive belts, or switches. Use a good lubricant such as Silicon Lube G331L
or Lubricate (00).
Service Check
Before aligning the mechanism, wipe off any accumulated dirt with denatured alcohol. Wipe around parts
where the tape contacts and around all rotating parts. Drive belts are specially processed. Do not clean
them with alcohol.
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