Hedghog programmable standards converter

HEDGHOG PSC

PROGRAMMABLE

STANDARDS CONVERTER

Hedghog PSC is a homebrew programmable standards converter. From a 625 or 525 line input it is capable of generating a wide range of Television line standards. It is coupled with a versatile programmable modulator that uses two MC44BS373.

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.

FEATURES OF CONVERTER

The converter can generate the following

Field frequencies of 25, 30, 50 and 60 Hz
Number of lines between 16 and 830
Number of active lines(lines with picture information) between 8 and 800
Adjustable length of front porch, line sync, back porch and broad pulse.
Number of broad pulses between 1 and 50.
Sync height of 20, 25, 30, 35, 40, 45 and 50%
Independent left and right crop
Selectable equalising pulses
Test patterns: Test card, Grey scale, Crosshatch, Cruciform, Black screen, White screen

FEATURES OF MODULATOR

Frequency coverage 28.5 to 900 MHz in 5 ranges
Frequency ranges and step:

28.5 to 56.25 MHz step 15.625 KHz

56.25 to 112.5 MHz step 31.250 KHz

112.5 to 225 MHz step 62.500 KHz

225 to 450 MHz step 125 KHz

450 to 900 MHz step 250 KHz

Selectable negative video FM sound or positive video AM sound
Selectable vision/sound carrier separation of 4.5, 5.5, 6.0 and 6.5 MHz or when in positive video AM sound mode the video and sound carriers can be set independently(Variable mode)
Selectable picture/sound carrier ratio of 12 and 16 dB or fixed at 6dB when in Variable mode
Can be used as a stand alone modulator

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.

July 2021 I have updated the FPGA and PIC programming files.

The update allows the converter to convert from 525 lines as well as 625 lines. It automatically detects the input standard. Also included in the update are some test patterns. The patterns are applied before the converter so are available on all output standards.

DOWNLOADS

Menu description (.pdf)

Circuit diagram (.pdf)

Component list (.pdf)

Component layout top (.jpg)

Component layout bottom (.jpg)

Front and rear panel legends (.pdf)

FPGA program file (.jic)

Microcontroller program file (.hex)

LINKS

FRONT