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
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
Hedghog II
Hedghog II is mainly in response to the recent trouble with the EP2C5 FPGA boards.
Hedghog II for the most part it is the Same as Hedghog but with a few changes.
The biggest difference is the FPGA board is dispensed with. Now all the components are mounted on a single PCB.
The FPGA is changed to a more modern EP4CE6E22C8N.
The R2R DAC is changed from 9 bit to a 10 bit.
It now can be used in modulator only mode.
The video out socked is moved to the rear panel and an extra toggle switch is added to the front panel.
The DIP switch is now a 6 pole type.
It has a test mode that drives the Test card from the 50 MHz clock. This will allow the 405 side of the FPGA to be tested without the video clock been required and so should help to identify video decoder problems.
There are some circuit changes.
A 50 MHz oscillator feeds the FPGA. All other clocks are referenced from the 50 MHz clock. This includes a 14.31818 MHz clock for the video decoder which previously required it's own crystal.
The pull-up resistors for the switches have been removed and it now uses the weak pull-up's provided by the FPGA.
The unused section of the video amplifier chip is now used together with a analogue switch to enable it to be used in modulator only mode.
To provide all the required power rails there are now 5 voltage regulators 5V, 3.3V, 2.5V, 1.8V and 1.2V.
It still fits on a double sided PCB of the same dimensions as the Hedghog PCB and so will fit the same case.
All the files needed to build it can be downloaded here.
Frank
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