NL254 – Ratemeter
The NL254 calculates, using digital circuitry, the ‘instantaneous frequency’ of each interval in trains of events, uses a 3 digit display to show the rate in pulses per second or pulses per minute and produces an analogue voltage which is proportional to this rate. It features an adjustable threshold so that additional modules for detecting peaks (such as theNL201 Spike Trigger) should not be necessary.
NL506 – Analogue Switch
The NL506 contains a single pole change-over analogue switch. The state of which is controlled by a logic signal. This signal can be generated externally or by the internal Flip-Flop that can be toggled by the negative going edge of a logic input. A front panel switch allows direct selection of the switch state which is indicated by an LED.
NL703 – EMG Integrator
The NL703 EMG Integrator module was designed to produce an analogue signal to represent the amount, or strength of muscle activity. The unit accepts signals up to +1V, which are first full wave rectified and then applied to a “leaky integrator” within the module. The output of the integrator is buffered and the overall gain is set at unity. The time constant of the integrator is selected by a 6 position rotary switch.