Gas scintillation proportional counters (SPC) onboard TENMA provided
a powerful tool to study cosmic X-ray sources. Their high sensitivity
enabled us to trace the 283 sec pulsation from an X-ray pulsar Vela
X-1 with a high data quality. Also their excellent energy resolution
provided us with a high quality X-ray spectrum from this source,
in which the iron K-line emission is clearly seen.
The TENMA observed a recurrent activity of the Rapid Burster in
July 1984. An example of the typical type II bursts is shown here.
One of the remarkable features of the type II burst is its rapid
repetition with an interval of tens seconds to several minutes which
is linearly proportional to the total energy emitted in the proceeding