CHAMP ELECTRONICS -" THE VINTAGE VALVE AMP HOSPITAL"
NOTTINGHAM, ENGLAND
REPAIR OF DAMAGED CHINESE "AOIN" MODEL MC-10K
AMPLIFIER
A. BEFORE WORK CARRIED OUT:
"This is a Chinese Hi-Fi amplifier, 40 watts per
channel, belonging to Mr Richard Prentice of Mansfield, Nottinghamshire.
Mr Prentice brought me this amplifier quoting "you'll never get this
working again!?" On examination it was clear what had happened -
the power transformer primary had shorted in such a way as to put all the
secondary voltages sky high. This in turn had caused a massive arc across a
pair of the EL34 output tube plates to ground, resulting in a fire of the
fibre glass circuit board!
A re-wind of the power transformer and a few hours
painstakingly rebuilding the circuit by hand eventually saw her burst back
into life.
The EL34's in the photos are a mish-mash of used ones
for testing repairs before putting the originals (or new) ones in.
Mr Prentice was well pleased with the results to say
the least." - John.
B. DURING/AFTER WORK CARRIED OUT:
The glow of the tubes in the dark !!