The TADD-3 is a distribution amplifier for digital pulses. Its primary use is to distribute 1 pulse-per-second ("PPS") signals such as those obtained from GPS timing receivers.
The TADD-3 has six low-impedance outputs that deliver greater than 3.5 volts into a 50 ohm load, with rise time at the connector of less than 3ns. It also has two RS-232 level outputs that can be used to feed computer timing applications.
These outputs can be driven from one or two inputs, and the output polarity of each channel can be independently set. A multi-purpose input circuit allows direct input of TTL level signals, or other levels via an adjustable high-speed comparator. The inputs can be terminated in 50 ohm, 4.7kohm, or 1mohm loads.
The 12 volt power input is fused and protected against reverse polarity. Current drain depends on the number of loads and ranges from 70 to 250ma.
The RF and DC inputs are arranged so that two (or more) TADD-3 boards can be stacked, sharing common signal and DC inputs.