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Mike Phelan · 17th Feb 2004, 9:51 am

Right - here are a few to start the ball rolling.

Hybrid Pye colour 691/693/697 - sorry no component numbers.

Weak line and frame sync - contrast pot gone high
Sound distortion and buzz - adjust slope detector coil on IF strip
No line sync - 47k 2w feeding line pulses to f/w sync burnt up
Line osc stopped or wrong speed - 100k/120k in series with hold control O/c
Reduced width - valves OK, HT OK - shift choke on LOPTx
Ripples on lines - metal LOP chassis type. Solder (yes!) earth lead to line osc coil can
PCL84s overheating and low anode volts. Replace valves and reduce grid leak resistors to 680k
Reference osc stopped or intermittent - 2 x 4700pf
polystyrene caps

17th Feb 2004, 9:51 am	#1
Mike Phelan Dekatron Join Date: Nov 2003 Location: Near Leeds, West Yorkshire, UK Posts: 4,609	Pye hybrid colour stock faults Right - here are a few to start the ball rolling. Hybrid Pye colour 691/693/697 - sorry no component numbers. Weak line and frame sync - contrast pot gone high Sound distortion and buzz - adjust slope detector coil on IF strip No line sync - 47k 2w feeding line pulses to f/w sync burnt up Line osc stopped or wrong speed - 100k/120k in series with hold control O/c Reduced width - valves OK, HT OK - shift choke on LOPTx Ripples on lines - metal LOP chassis type. Solder (yes!) earth lead to line osc coil can PCL84s overheating and low anode volts. Replace valves and reduce grid leak resistors to 680k Reference osc stopped or intermittent - 2 x 4700pf polystyrene caps __________________ Mike.