Lexicon Prime Time 93 - In Case of Difficulty; Unit Will Not Power Up: Fuse Replacement

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5.0 IN CASE OF DIFFICULTY
Should you experience difficulty with your Model 93 the following information
should
be used as a guide for corrective action. It is assumed that the read-
er has already become familiar with operating and installation information in
this manual and that he is still experiencing difficulties.
WARNING
All servicing of the Model 93 should
be performed by qualified service per-
sonnel. There are hazardous voltages
located under both the top and bottom
covers of the Model 93. To avoid elec-
tical shock, remove power cord from
unit prior to removing covers. Ser-
vicing procedures consistant with good
safety practice should be used at all
times.
5.1 UNIT WILL NOT POWER UP: FUSE REPLACEMENT
If the M.93 will not power up, first check the line cord and service outlet.
Next check the power fuses. To gain access to the fuses, first remove the
power cord and then remove the top cover screws and top cover. The main
power fuse, F2, is located beneath a plastic shield in the front left corner
(facing the
unit). The +5V power supply fuse, Fl, is located to the rear
left side. Check the fuses for continuity with a continuity tester or ohm
meter. If a fuse is open, replace it with an exact replacement fuse: Fl is
a type 7AG 2~ Amps. F2 is a type 3AG 3/4 Amp slow blow for ll5V operation;
type
3AG 3/8 Amp slow blow for 230V operation.
To access F2, remove the plastic shield by depressing each of the small lock-
ing barbs
on the three nylon standoffs while simultaneously lifting the shield
at the nearest corner. The barb can be depressed with a small pliers or
screwdriver. Replace the fuse.
Then snap the insulating plastic shield back
onto the nylon standoff making sure that all barbs lock in place.