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fsphil / hacktv

Analogue TV transmitter for the HackRF
GNU General Public License v3.0
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Shouldn't the teletext lines be active all the time... #61

Closed Zcooger closed 4 years ago

Zcooger commented 4 years ago

...regardless of available teletext page amount? Small comparison: ds030 ds006

fsphil commented 4 years ago

Not necessarily. If you're just transmitting a single magazine, there will be blanks due to the 20ms rule:

For compatibility with earlier decoders in the field, a page clearing interval of 20 ms should be maintained in the transmission between the header and any packets of a page that is intended to be interpreted by a Level 1 or 1.5 decoder. This time interval is required by many decoders for erasing the previous page from memory