The "$50sat rtty decoder"  decodes the RTTY telemetry sentence.

$50SAT,128,,438,,,62,3,,21,129,83,,142,281,3703,*51
$50SAT,128,,443,,,49,3,,21,144,82,,102,281,3662,*44
$50SAT,128,,443,,,52,3,,21,141,83,,102,281,3662,*4A
$50SAT,128,,443,,,57,3,,21,135,83,,122,281,3683,*41
$50SAT,128,,445,,,64,3,,21,132,84,,122,283,3723,*4E
$50SAT,128,,445,,,62,3,,21,134,83,,122,283,3723,*49
$50SAT,128,,445,,,56,3,,21,140,83,,102,283,3703,*4D
$50SAT,128,,448,,,52,3,,21,141,83,,102,286,3662,*46
$50SAT,128,,448,,,55,3,,21,138,83,,102,286,3683,*40
$50SAT,128,,452,,,55,3,,21,138,83,,102,290,3683,*4C
$50SAT,128,,452,,,58,3,,21,134,83,,122,290,3683,*4F
$50SAT,128,,457,,,53,3,,21,140,82,,102,295,3662,*4B
$50SAT,128,,457,,,56,3,,21,137,83,,102,295,3683,*40
$50SAT,128,,462,,,56,3,,21,136,83,,102,300,3683,*4A
$50SAT,128,,462,,,62,3,,21,,82,45,4122,300,3703,*7D
$50SAT DECODER SCREEN
FOUR GRAPHICS PARAMETERS RFMTEMP, PCBTEMP, SOLAR VOLTS, BATTERY VOLTS
Unfortunately the $ 50sat stopped working in July 2015, after being in operation for over a year and a half.