HEDGHOG L

405/819 Line STANDARDS CONVERTER

Hedghog L is a homebrew standards converter. From a 625 line input it will generate 405 line or 819 line standards . It is coupled with a versatile programmable modulator that uses two MC44BS373.

This converter uses the Lattice iCE40HX1K FPGA. When compared to the FPGA's used in previous Hedghog's it is very small. The standards converter had to be heavily pruned back in order to get it to fit within the iCE40HX1K. While the standard of the output isn't up to the standard of previous Hedghog's it still gives a reasonably good conversion. In order to get more functionality multiple program images are stored in flash memory and loaded as required.

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.

CONVERTER FEATURES

405 line standards converter with 4:3 => 4:3, 4:3 => 5:4, 16:9 => 4:3, 16:9 => 5:4 aspect ratio conversion.
Selectable equalising pulses when converting to 405 lines
405 line Test card
819 line standards converter

MODULATOR FEATURES

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