@58997ea5 

$GPGSV,1,1,00,0*65
$BDGSV,1,1,00,0*74
$GNTXT,1,1,01,ANTENNA OPEN*3B
$TDINF,Techtotop Multi-GNSS Receiver*63
$TDINF,T3,RomFw,1.1(48),Aug 12 2016 16:57:35*02
$TDINF,GNSS=BDS+GPS,ANT=Integrate*6A 

 @58997ea5 So, it sounds like techtotop is a big Chinese vendor that ships GNSS chips..