Martel Electronics 135 - Manual (Page 68)

5.
Replace the blown fuse with a new one of the proper type.
6.
Reassembly is essentially the reverse of the above procedure.
Position the cover loosely and attach the keypad connector.
Carefully lower the cover into place, making sure it clears the
power supply PCB at the top and aligns with the jacks at the
bottom. Before installing the screws, turn the unit on and check
the keypad operation. Testing any horizontal row of keys will
verify that all contacts are properly made. Turn the unit back off
and reinstall the screws.
Service Information
130/135 64
NOTE: Spare fuses are shipped with each calibrator. Additional
fuses may be obtained from Martel Electronics Corp. or from
local distributors.
The milliamp output fuse
(F2-Model 130, F3-Model 135) will blow if the mA+ output terminal is
shorted to the Volts- or Frequency- terminals even momentarily. This
most often happens while changing test lead connections when
individual leads are used. If individual leads are used, the mA+ lead
should always be disconnected first and reconnected last.