A tunable multiplex discriminator with digital output

The unit to be described differs from present tunable discriminator products chiefly because it is designed to simultaneously demodulate all the subcarrier channels in a frequency division multiplex. In addition the demodulated output data is presented in digital format that is compatible for direct computer entry. The discriminator implementation techniques will be discussed at the block diagram level. Particular emphasis will be given to the use of 'Finite Impulse Response' filters and also to the internal tape speed compensation process.