Fabulous Finlandia; 1982 Granada C22XZ5
Tales of woe after the storms. (2007)
Live Aerial Mast
Total collapse
What Not To Do
1983 Philips 26CS3890/05R Teletext & Printer
MRG Systems ATP600 Databridge
Teletext Editing Terminal
Microvitec Monitor 1451MS4
BBC Microcomputer TELETEXT Project
Viewdata, Prestel, Philips
Philips Model Identification
1976/77 Rank Arena AC6333 – Worlds First Teletext Receiver
PYE 1980s Brochure
Ceefax (Teletext) Turns 50
Philips 1980s KT3 – K30 Range Brochure
Zanussi Television Brochure 1982
Ferguson Videostar Review
She soon put that down
1983 Sanyo Brochure
Wireless World Teletext Decoder
Unitra Brochure
Rediffusion CITAC (MK4A)
Thorn TRUMPS 2
Grundig Brochure 1984
The Obscure and missing Continental
G11 Television 1978 – 1980
Reditune
Hitachi VIP201P C.E.D Player
Thorn 3D01 – VHD VideoDisc Player
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
Suggestions
Website Refresh
Colour TV Brochures
Fabulous Finlandia; 1982 Granada C22XZ5
Tales of woe after the storms. (2007)
Live Aerial Mast
Total collapse
What Not To Do
1983 Philips 26CS3890/05R Teletext & Printer
MRG Systems ATP600 Databridge
Teletext Editing Terminal
Microvitec Monitor 1451MS4
BBC Microcomputer TELETEXT Project
Viewdata, Prestel, Philips
Philips Model Identification
1976/77 Rank Arena AC6333 – Worlds First Teletext Receiver
PYE 1980s Brochure
Ceefax (Teletext) Turns 50
Philips 1980s KT3 – K30 Range Brochure
Zanussi Television Brochure 1982
Ferguson Videostar Review
She soon put that down
1983 Sanyo Brochure
Wireless World Teletext Decoder
Unitra Brochure
Rediffusion CITAC (MK4A)
Thorn TRUMPS 2
Grundig Brochure 1984
The Obscure and missing Continental
G11 Television 1978 – 1980
Reditune
Hitachi VIP201P C.E.D Player
Thorn 3D01 – VHD VideoDisc Player
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
Suggestions
Website Refresh
Colour TV Brochures
B&W TV Valve era vertical circuits by HMV in Oz
I've been following some UK TV designs, which seemed to change quite frequently over the years.
HMV in Australia was part of the EMI group. Their first TV, the E1-A1 chassis, although it performed well, was somewhat of a disaster for EMI (the UK-sourced CRTs and LOPTs all failed inside the 3 months warranty) so the E1-A1 became the E1-A2 very quickly, using locally-sourced CRTs and LOPTs.
The -A2 introduced an interesting vertical circuit that was to survive with only minor changes right through to the end of the valve era. It used a current-to-voltage transformer to implement yoke current sensing feedback, a technique that was to be used almost universally in solid state designs right up to the end of the CRT era. Other advantages were that performance was maintained with valve aging and, theoretically, there was no need for a linearity control (although HMV relented and put one in later versions).
Here are 3 example circuits - the order is reversed!
The first is from 1956 and the E1-A2. Note there is no vertical linearity control. 6BM8 = ECL82
The 2nd is HMV's first 110 degree chassis, circa 1959. Different valves, same circuit. The drive to the yoke is now balanced to eliminate horizontal crosstalk through the yoke that would degrade the interlace.
The 3rd circuit is from the last all-valve chassis, circa 1969. We now have the 6GV8 / ECL85 and some tweaks to the vertical oscillator, but still recognizably the same circuit.
HMV changed overall physical chassis designs 4 times in the early years. The final one was an engineer's dream that folded down flat
to provide easy access to everything. This same chassis pressing was to remain largely unchanged for nearly 15 years, except for big rectangular holes that appeared to accommodate the PCBs of the hybrid chassis.
The mention of the hybrid chassis reminded me of how the circuit morphed into the solid state era.
Transistors have replaced the triode, the blocking oscillator transformer and the current-to-voltage transformer.
The by-then-quite-old 6CW5 makes a re-appearance!
The Kolster-Brandes model HV40 employs a feedback transformer in the frame timebase output stage. Result is excellent linearity and and ease of adjustment.
Till Eulenspiegel.
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