This site contains historical information on equipment designed and built in the Gaithersburg plant of Watkins-Johnson, the Bethesda plant of Communication Electronics, Inc and the Rockville plant, which produced both CEI and WJ equipment.

This site is not affiliated in any way with past or present owners of the Gaithersburg facility
(Watkins-Johnson, BAE, Signia-IDT, DRS Technologies or Finnemeccania)

Get the June 2009 issue of Popular Communications magazine to read "The Father of Modern Spy Radios", covering the origins of post WWII American made surveillance radios.

Allen S. Clarke has all but disappeared from radio history, but his companies, Clarke Instruments and Nems-Clarke nurtured a number of engineers who went on to play key rolls in establishing American's superiority in VHF and UHF radio design.

Ralph Grimm was Clarke's third employee. Grimm, with Clarke's assistance, founded CEI, which became the Gaithersburg division of Watkins-Johnson, a preeminent source for high performance VHF and UHF radios.

Progress Report

11-8-09 - Barry Narod, Adjunct professor of Earth and Ocean Sciences University of British Columbia donated a collection of early Watkins-Johnson component catalogs from the West Coast operations. They will be filtering onto the site as time allows. These are for VCOs, mixers, YIGs and other parts made in Scotts Valley, San Jose and/or Palo Alto. The first one, a VCO catalog, can be found on the Site Document Index.

8-30-09 - A RARE FIND ADDED - full service manual for the Mason A-3B suitcase countermeasures receiver. See the Site Document Index page in a section called Other Manufacturers.

8-30-09 - I decided to add watermarks to all the documents on this site. I have never liked to see them on other sites but I now understand. It takes tremendous time, energy and a certain amount of money to locate these documents, pictures and information. The internet may appear to be free and many people feel they can freely use things with no attribution, but someone does the work and someone deserves the credit even when they do not charge for their efforts.

3-25-09 -COMING SOON - In the June 2009 issue, Popular Communications will publish my history of Nems-Clarke and Clarke Instruments. This article shows the early origins of the modern surveillance receiver. It also covers some of the connections between receiver manufacturers appearing on this site.

(Old News)

For documentation or help, please try the folks
on the manuals or service work links above.

I do not sell or broker equipment, manuals or service work.
I am not a clearinghouse for information or documentation.
Most of this equipment is rare and documentation and/or software is even more rare.
Please do not be offended if I do not respond to your e-mail.
I receive many requests, often with apologies and pleas of desperation.

This site is also gathering size and becoming unwieldy to edit.
If you see anything wrong or find any broken links, please let me know.
Contact me at watkins-johnson at terryo dot org