HB101

H-B101 was one of the early beam switching tube introduced im the late 1955 by Haydu Brothers together with the early Nixie display tube. The prefix itself, H-B, looks to be the acronym of Haydu Brothers. H-B101, registered as 6701, was the low-voltage variant of the MO-10, with reduced magnetic field.
20V target typical voltage, 0.7 mA, 6.8 kohms load.
In Electronics, December 1955, this tube was advertised as produced by 'Haydu Brothers of New Jersey', subsidiary of Burroughs Corporation.
Operating principle of trochotron.
Haydu or Burroughs: the early trochotron tube.