Eaton-Peabody Laboratory

I am employed at the Eaton-Peabody Laboratory of Auditory Physiology as a Senior Research Support Engineer. EPL is a consortium between the Research Laboratory of Electronics at the Massachusetts Institute of Technology (my Alma Mater), the Massachusetts Eye and Ear Infirmary, the Massachusetts General Hospital, and Harvard Medical School.

The Laboratory staff includes faculty from both MIT and Harvard Medical School. Undergraduates from both Harvard and MIT work on various projects during the summer, while graduate students and post-docs work year round (and sometimes round the clock) on interdisciplinary research teams. A number of graduate students in the Health Sciences and Technology (HST) Speech and Hearing Program are involved in research here.

My responsibilities entail maintaining a network of computers including Macintosh, Sun, VAX, NeXT, SGI and even PC platforms, including support of both system and application software; design and construction of analog and digital systems for instrumentation, as well as doing or arranging for machining and electrical systems work.

Another large chunk of time goes to assisting students and researchers learn how to use new (or old) pieces of equipment or software - or trying to mediate between user expectations and hardware / software capabilities.

Notable Accomplishments

Graphics terminal emulator for the LINC (1974)
Assembly code for the LINC to emulate (after a fashion) an IMLAC display processor.
Programmable Timing Generator (1974)
Computer-controlled eight channel digital delays, gates, and pulse trains, a versatile laboratory instrument.
Programmable Oscillator (1976 & 1991) A direct-digital synthesizer, remarkable in its time for low cost, ease of computer interface, and no relays or trimpots to wear out or need adjusting.
Interaural Delay Line (1979) Delay of an audio signal in 10 microsecond steps for sound localization experiments - computer or manually controlled.
Multichannel Event Timer (1988) Precise time-stamping of events for later correlation and statistics analysis.
Precision Step Attenuator (1989) A multichannel computer controlled audio attenuator with range from 0 to -130dB in 0.1dB steps, minimal phase shift and rolloff from DC to well over 50kHz.

This is not to say that nothing else was going on in the interim, but much work during these years was for computer systems that no longer exist! Things like programming high quality vector fonts for incremental plotters, graphics drivers for the Versatec electrostatic printer-plotter and any other graphics devices that came in, enhancements to the FOCAL programming language that were breakthoughs in their day, but are only history now. Also file transfers, conversions and updates through a succession of operating systems, such as LAP-6, OS-8, RT-11, VAX-VMS, Unix System 6, Ultrix, Sun-OS and where to next?

Other projects can be found on my Engineering Notes page.

Corrections, additions or comments?
Send email (if supported by your browser) to the author, ijs@mit.edu.
Original June 22, 1994
Last Modified: Jun 10 19:36 EDT 2008 / ijs