Granada Television Brochure, 1970s
Long Gone UK TV Shops
Memories of a Derwent Field Service Engineer
PYE Australia Circa 1971
Radios-TV VRAT
Fabulous Fablon
Thorn TX10 Chassis
Crusty-TV Museum, Analogue TV Network
Philips N1500 Warning!
Rumbelows
Thorn EMI Advertising
Thorn’s Guide to Servicing a VCR
Ferguson 3V24 De-Robed
Want to tell us a story?
Video Circuits V15 – Tripler Tester
Thorn Chassis Guide
Remove Teletext Lines & VCR Problems
Ceefax (Teletext)
Suggestions
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Colour TV Brochures
1970s Lounge Recreation
CrustyTV Vintage Television Museum
Linda Lovelace Experience
Humbars on a Sony KV2702
1972 Ultra 6713
D|E|R Service “The Best”
The one that got away
Technical information
The Line Output Stage
The map
Tales of a newly qualified young engineer.
Tales of a Radio Rentals Van Boy
Sanyo SMD
Disastrous Company Rebranding
1969 Philips G22K511
Memories Of The TV Trade
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Dirty TV screens
Dual Standard and Single Standard CTV’s
Radios-TV on YouTube
The Winter of 62/63
A domestic audio installation
1979 Ferguson Videostar Deluxe 3V16
Music centre modifications
Unusual record player modification
B&K 467 Adapters
Mishaps In The Trade
1971 Beovision 3200
1971 Bush CTV1120
Granada Television Brochure, 1970s
Long Gone UK TV Shops
Memories of a Derwent Field Service Engineer
PYE Australia Circa 1971
Radios-TV VRAT
Fabulous Fablon
Thorn TX10 Chassis
Crusty-TV Museum, Analogue TV Network
Philips N1500 Warning!
Rumbelows
Thorn EMI Advertising
Thorn’s Guide to Servicing a VCR
Ferguson 3V24 De-Robed
Want to tell us a story?
Video Circuits V15 – Tripler Tester
Thorn Chassis Guide
Remove Teletext Lines & VCR Problems
Ceefax (Teletext)
Suggestions
Website Refresh
Colour TV Brochures
1970s Lounge Recreation
CrustyTV Vintage Television Museum
Linda Lovelace Experience
Humbars on a Sony KV2702
1972 Ultra 6713
D|E|R Service “The Best”
The one that got away
Technical information
The Line Output Stage
The map
Tales of a newly qualified young engineer.
Tales of a Radio Rentals Van Boy
Sanyo SMD
Disastrous Company Rebranding
1969 Philips G22K511
Memories Of The TV Trade
Crazy house
Dirty TV screens
Dual Standard and Single Standard CTV’s
Radios-TV on YouTube
The Winter of 62/63
A domestic audio installation
1979 Ferguson Videostar Deluxe 3V16
Music centre modifications
Unusual record player modification
B&K 467 Adapters
Mishaps In The Trade
1971 Beovision 3200
1971 Bush CTV1120
CTV Philips G6 single-standard CTV, varying brightness.
This set is has a varying brightness fault. Assuming the PFL200 video amplifier is OK, in order to carry out fault finding the operation of the brightness control should be studied first. My take on the circuit is in the brightness control system a proper black level reference system is employed. Transistor T2146 conducts only during the back porch after the sync pulse. The negative going sync pulses from the anode of the sync separator are differentiated by C2002 and R2107. The result is a negative going leading edge and positive going trailing edge. Diode X2152 conducts on the positive going trailing edge of sync pulse and supplies the base of T2146 with the black level reference pulse. The voltage on the emitter of transistor T2146 determines the brightness control setting.
Lockfit transistors are becoming unreliable so T2146 (BC148) should be replaced first before any fault finding measures.
Till Eulenspiegel.
Hi David
Many thanks for your description of the brightness circuit in my G6 . The brightness was varying for a couple of days then the picture went very bright . The brightness control works but even on minimum setting it's still too bright . The set has done well as it's over a year ago since it had a fault and it's used at least 4 times a week
Hi Gary, it's possible the negative 24volt supply is causing the fault condition. Check C1030 and X1114 in the power supply section and C2001 on the signals panel.
Till Eulenspiegel.
Many thanks for that David , I'll get started with it on Saturday and post my findings.
Hi Everyone
I finally got to look at the G6 brightness problem, it turned out to be nothing more than a faulty pfl 200. I fitted a nos pfl 200 and the picture is back to normal. Now I'm wondering , should I log the repair on the mastercare repair card that came with the set of should I leave it with the last log which was 1981.
Make a copy of it and fill out the copy! Looks a good picture 🙂
Regards
Lloyd
Hi Lloyd
I think that's a good idea , I will copy the service card and fill in the repairs done so far
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