George Joseph Frye (? – ?) co-invented the random sampling technique.
George Frye grew up in Kansas City, Missouri and attended Rockhurst High School in Kansas City. After that, he attended Rockhurst College as a physics major. He transferred to the University of Kansas and studied electrical engineering. As an undergrad project, he built a carrier current system for the campus. During these early years, George was active on ham radio (W0EZU) and eventually worked all continents.
During undergrad, Frye worked at Wilcox Electric, initially in shipping, later on the assembly line, soldering, and later helping debug 10 kW shortwave transmitters.
As a grad student, also at the University of Kansas, under Professor Norris Nahman, he developed the random sampling technique under a grant from the US National Security Agency.
“But then realized that an NSA project I worked on while going for my MSEE at KU showed the way to generate real time sampling pulses at very high frequencies.
Just use a klystron. Velocity modulate the beam at the desired sampling frequency and then place a catch electrode at the point where the electrons combine in pulses at the modulating frequency. Klystrons usually place a cavity there to collect the amplified RF signal.
That was the basis for the project I was assigned to 60 years ago…”
While still in Kansas City, he took a job at Bendix Corporation. That was work for the Department of Defense.
George's first assignment at Tek was to build a high speed (around 100 MHz) square wave waveform generator for internal purposes. It didn't go into production.
After Norm Winningstad left Tektronix in the mid-1960s, George Frye's manager was Al Zimmerman.
Frye is listed as "Project Engineer, Electrical" on the 4S2A sampling plug-in for the 661. In the late 1960s, he was involved ("head man") with the development of the S-1 and S-2 sampling heads. The sampling technology used in those sampling heads was similar to previous instruments, just modularized.
In terms of making high speed sampling heads, Tek was at a disadvantage compared to HP because HP had faster snap-off diodes. This enabled HP to generate very sharp sampling strobe pulses and therefore achieve small aperture time and therefore good high frequency response. George Frye pondered how to build a very fast (low aperture time) sampler using the components Tek had at the time. He decided to leverage the very short turn-off time of Tek's Schottky diodes. This led to the invention of the traveling wave sampling gate, US patent number 3629731. In this new sampling gate design, the aperture time is not a function of the length of the sampling strobe pulse. Only the falling edge matters. Another way of viewing this is that conventional sampling heads depended on the sampling pulse having a high second derivative, whereas the new design only required a high first derivative. This led to a significantly faster sampling head. The first product using this new sampling gate design was the S-4, which has a rise time of 25 picoseconds.
Frye Electronics produces instruments for measuring the performance of hearing aids. As of May 2023, George is still actively involved with Frye Electronics.
- George Frye and Norris S.Nahman, Random Sampling Oscillography. IEEE Transactions on Instrumentation and Measurement, Vol. IM-13 Issue 1, March 1964
- George Frye, A new Approach to Fast Gate Design, 1968 (also in Servicescope No. 52, Oct 1968)
- George Frye, A Predictable Subnanosecond Step Generator. IEEE Transactions on Instrumentation and Measurement, Vol. IM-17 No. 4, December 1968
Documents Authored by George Frye
|062-1244-00.pdf||Book||Measurement Concepts: Time-Domain Reflectometry Measurements||James A. Strickland • H. Allen Zimmerman • Gordon Long • George Frye||1969||TDR • 3S7 • 3T7|
Products by George Frye
|4S2||Plug-in||Dual channel sampling plugin||George Frye||1962|
|4S2A||Plug-in||Dual channel sampling plugin||George Frye||1965|
|S-4||Plug-in||Sampling Head||George Frye||1968|
|7T11||Plug-in||Sampling Sweep Unit||George Frye • Al Zimmerman • Gene Cowan||1969|
|7S11||Plug-in||Sampling plugin||George Frye • Al Zimmerman • Gene Cowan||1969|
|7T11A||Plug-in||Sampling Sweep Unit||George Frye • Al Zimmerman • Gene Cowan||1986|
Components by George Frye
|155-0001-00||Hybrid integrated circuit||gate assembly||George Frye||S-4|
|155-0053-00||Hybrid integrated circuit||sampler||George Frye||S-6|
- Project Engineer on 4S2A (1966; see Tektronix 4S2A Engineering Specification)
- Designed S-4 Sampling Head (1968)
Patents by George Frye
|Page||Office||Number||Title||Inventors||Company||Filing date||Grant date|
|Patent US 3281705A||US||3281705A||Wide band signal inverter circuit having separate paths for high and low frequency signal portions||George Frye||Tektronix Inc||1964-02-03||1966-10-25|
|Patent US 3297885A||US||3297885A||Variable width pulse generator employing independently operated switches for controllably discharging transmission line||George Frye||Tektronix Inc||1964-03-06||1967-01-10|
|Patent US 3309532A||US||3309532A||Wave shaping and voltage limiting circuit employing plural snap-off diodes||George Frye||Tektronix Inc||1964-03-20||1967-03-14|
|Patent US 3344285A||US||3344285A||Ramp generator and comparator circuit employing non-saturating gate||George Frye||Tektronix Inc||1965-01-19||1967-09-26|
|Patent US 3434049A||US||3434049A||Time domain reflectometry system having a current source for locating discontinuities in a transmission line||George Frye||Tektronix Inc||1965-12-06||1969-03-18|
|Patent US 3524993A||US||3524993A||Triggering method and apparatus wherein the triggering period is determined||George Frye||Tektronix Inc||1967-02-17||1970-08-18|
|Patent US 3629731A||US||3629731A||Sampling system||George Frye||Tektronix Inc||1968-07-12||1971-12-21|
|Patent US 3612915A||US||3612915A||Triggerable apparatus||George Frye||Tektronix Inc||1969-05-26||1971-10-12|
|Patent US 3611003A||US||3611003A||Oscilloscope signal sampling system||George Frye||Tektronix Inc||1969-05-26||1971-10-05|
|Patent US 3612910A||US||3612910A||Triggered pulse generator having automatic bias adjustment||Gene Cowan • George Frye||Tektronix Inc||1970-07-28||1971-10-12|
|Patent US 3747002A||US||3747002A||Time and sequence determining circuit||George Frye||Tektronix Inc||1971-04-29||1973-07-17|
|Patent US 3881133A||US||3881133A||Two dot indicator system||George Frye||Tektronix Inc||1973-06-18||1975-04-29|
|Patent US 4069447A||US||4069447A||Stabilized high-efficiency sampling system||George Frye||Tektronix Inc||1974-08-19||1978-01-17|
|Patent US 8995674||US||8995674||Multiple superimposed audio frequency test system and sound chamber with attenuated echo properties||George Frye||Frye Electronics Inc||2012-05-30||2015-03-31|
Links and References
- George Frye: Family Need Leads To A Better Hearing Aid And A New Industry. Electronic Design, Nov 2008
- Frye Electronics: History