The images seem a bit scrambled, presumably due to missing data blocks. At that low a resolution, have you considered maybe Robot36 SSTV?

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radeeyate 2 hours ago | parent [-]

Images are all in order, but some have missing packets.

The problem with SSTV is the power required. From some looking it seems that transmitting would need at least 5 watts. This wouldn't be feasible running on the balloon, as it was powered by Energizer Ultimate Lithium batteries.

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ErroneousBosh 21 minutes ago | parent [-]

Oh, yeah FM transmitters can require a fair bit of power.

What is it using then, LoRA type stuff?

	▲	radeeyate 2 minutes ago \| parent [-]
		Yep, the radio link runs LoRa on the 33 cm band (915 MHz)