ENDEVCO MODEL 136 DC AMPLIFIER
INSTRUCTION MANUAL
IM136
Page 2
SECTION 1: GENERAL DESCRIPTION
1.1
INTRODUCTION
ENDEVCO has remained a leader in the vibration measurement field since 1951, and has
contributed many firsts in vibration sensor design. These include: the first piezoelectric
accelerometer capable of continuous operation from cryogenic temperatures up to +750°F,
the first shear design accelerometer and the world's smallest piezoelectric accelerometer. To
support a broad family of vibration transducers, ENDEVCO has provided a wide variety of
signal conditioners, including the first transistorized charge amplifier, the first computer-
programmable charge amplifier and the first airborne vibration monitoring system that is
based on a true digital tracking filter.
SIGNAL CONDITIONERS
To support the use of its sensors in large scale testing, ENDEVCO has developed several
generations of signal conditioner systems. Until recently, a state-of-the-art vibration
laboratory set up consisted of a rack of manually controlled signal conditioners. These signal
conditioners have manually controlled switches and knobs, to set full scale ranges, sensitivity
and filter corners and the set up information is recorded by hand.
COMPUTER CONTROLLED SIGNAL CONDITIONERS
To eliminate the risk of incorrect amplifier settings, ENDEVCO has pioneered the concept of
computer controlled signal conditioners. The first generation was the Multi-channel Amplifier
Control system (MAC). The second generation was the Computer Controlled Amplifier
Systems (CCAS). The CCAS family consists of five different systems that use the same rack
and digital interface assemblies with different analog boards. These units receive their setup
commands over an IEEE-488 interface bus from a computer/controller, so that tests can be
pre-programmed. In addition, these units provide comprehensive self-test and self-calibration
capabilities, which greatly improves the reliability of the test data. User feedback is indicated
that these units pay for themselves quickly by shortening test cycles, preventing retests and
eliminating over-testing.
MANUAL/COMPUTER CONTROLLED SIGNAL CONDITIONERS
The experience gained in the first two generations of computer controlled amplifiers has now
been applied to a third generation product line: the programmable bridge conditioner and the
programmable laboratory signal conditioner. These units are independently controlled and
each unit contains its own power supplies for single channel integrity.
The Model 136, has both manual and computer programmable features. This DC Amplifier is
an example of Endevco's commitment to improving the state-of-the-art in sensory
measurements. The new generation is smaller with more features and will continue to be
expanded to meet an ever widening range of application requirements.