HEDGHOG II
625 TO 405 LINE
STANDARDS CONVERTER
Hedghog II is a homebrew 625 to 405 line standards converter which is based on the Hedghog converter.
On this page you will find the files required to build it.
All material including Downloads on these pages are provided 'as is' without warranty of any kind, either expressed or implied.
A Hedghog II has all the features of Hedghog with the following differences. All the components are mounted on a single PCB. The FPGA is changed to a more modern Cyclone IV EP4CE6E22C8N. The DAC is changed from 9 bit to a 10 bit. It can be used as a System A modulator. The video out socket is moved to the back panel to make room for an additional toggle switch on the front.
NOTES All Resistors, Capacitors and Inductors are 0805 size. All Capacitors are ceramic multilayer types. Where given manufacturers part numbers are given as examples alternative parts may also suit. The PCB is double sided and measures 100 mm X 89.5 mm. Link to uploaded Gerber files on PCBWay.
DIP SWITCH FUNCTIONS Also when F is on the video port from the video decoder can be checked one bit at a time. If DIP switch F is on video coming through the converter can be corrupted and rolling horizontally/vertically. This is normal. As they all use the LED to display the result only one of the switches C to F can be on at a time. Otherwise the result will be unpredictable.
March 2020 Added 405 line to 625 line conversion capability. In August 2019 Jeffrey Borinsky successfully built a 625 to 405 standards converter. He detailed how he did it in a thread on Golborne Vintage Radio Forum. See link to the thread below.
There are a couple of caveats. Firstly I have no suitable VCR to record/playback 405 lines so I don't know how well it will preform with a VCR as source.
DOWNLOADS Component layout bottom (.jpg) Front and rear panel legends (.pdf) FPGA program file Dual Standards Converter(.jic) LINKS |
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