Picosecond Pulse Labs is now part of Tektronix. The same leading performance you have come to expect from Picosecond Pulse Labs products is now available with the worldwide support and backing of Tektronix.
Tektronix designs low-pass (risetime) filters that produce very clean transient responses. Risetime filters are also sometimes called Transition Time Converters or TTC's. These filters are based on a proprietary, absorption design that has frequency responses that are similar to Bessel-Thomson (B-T) filters, but provide superior transient response.