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“Baby Will” Valve Junior Conversion
Version 4
Build Manual
22 September 2009
34 of 36
9.3 Power Up with Tubes
9.3.1 The Real Test
Install the tubes!
Aren’t they pretty?
These measurements WILL match those on the schematic.
Verify the amp’s power switch is in the “OFF” position. Insert the mains power
cord in the IEC mains connector.
Secure the black ground lead of your voltmeter to the chassis star ground lug.
Plug the amplifier into a speaker cabinet. Match the speaker
impedance with the appropriate output jack. Failure to connect a
speaker will cause harm and eventual failure of the output transformer.
Switch the amp’s power switch to the “ON” position. With your voltmeter, check
the following voltages. If a significant deviation from these readings is observed,
turn off the amp, unplug the mains power and investigate.
