The valveking series of Peavey amps are valve amplifiers.
By "will power up" I take it you mean the power lamp is lit thus eliminating power plug, ac cord and on / off switch and main fuse from our investigations. Before we continue you must understand that valves are a voltage operated device and voltages around these components are dangerously high (200 to 400 volts is quite normal). Electricty is dangerous. You cannot see it, smell it or hear it. If you have any doubts about your ability to service this appliance do not proceed but seek help from your local srvice provider.
If you feel confident that your level of skill is good, then let us proceed. Unplug the appliance from the ac power and remove the chassis from the cabinet, you will now have access to the component side of the chassis. Reconnect the speaker. You will
require a multimeter (digital or analogue) set to the highest dc range. Connect the negative terminal of the meter to the chassis.
You are now ready to plug the amplifier into the ac power and switch on. Do all the valves light up in the output stage, can you hear a faint hum or buzz from the speaker. If all valves lit but no buzz disconnect ac power and measure dc resistance of speaker. If about 6 to 8 Ohms its ok. If infinite replace speaker. If ok reconnect ac power and continue with the next step. Measure the dc voltage on the anodes (plate) of each output valve and the voltage on the screen grids of the output valves. These should be in the region of serveral hundred volts. One word of advise when taking meaurements around high voltage circuits, KEEP ONE HAND IN YOUR POCKET. you will then be more likely to survive this exercise. If all appears good up to this point, locate the master volume control, turn it up to maximum. With a screw driver
and using only one hand touch the terminals of the control. Do you now hear a loud buzz from the speaker if yes the the output stage is ok, if not the the fault lies within the output stage.
When you have carried out all of the above, post a detailed report of your findings and we will continue with our diagnosis.
Good luck and be safe. Regards from Vintie
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So you've carried out my previous advice and you have been unable to get a stronge buzz from the output stage
Check and replace as necessary. Continuity of primary winding
Check and replace as necessary. Continuity of primary winding
output transformer. Check for open circuit screen feed resistors. Check anode and cathode resistors of phase splitter valve. Replace phase splitter valve.
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