The transmission of poise width modulated signals over restricted bandwidth systems

The apparent anomaly of transmitting FW signals, with pulse lengths as short as 90 microseconds, over restricted bandwidth systems with bandwidths in the order of 3 kc´s, are discussed. It has been shown that in reality, data is transmitted not as pulses of absolute length, but of relative length. However, resolution errors introduced using the techniques described do result in some increase in jitter. No attempt has been made to compare operating thresholds or to make S/N comparisons as such figures as are now available would not be indicative of system performance when using optimized FM/FM discriminator output, low pass filters.