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Black Radios - Home Page Radio Manufacturers Index Black Radios Document Index Historical Roots in Brief Watkins-Johnson - Home Page Supporting this Research WJ & CEI Document Index Sales & Clearance WJ-CEI Home Page My Publications Research Material Donations Bio and Contact Collector Corner (Articles by collectors on how-to, repairs and projects) Visit the BlackRadios Facebook page for discussions and sharing information Watkins-Johnson & Communication Electronics, Inc This is one public window to my ongoing research into Watkins-Johnson and Communication Electronics, Inc and the history of American telemetry and surveillance equipment manufacturers (COMINT, SIGINT and ELINT). For other companies please see my Black Radios website . New on the WJ & CEI Site October 14, 2023 - Section 1 of the operating manual for the WJ-8904B TEMPEST test receiver is now available. This is a huge beast of a receiver whose use was required by the DoD for TEMPEST certification during the 1980s. A receiver only a true believer or a museum would want own. It covered 5 kHz to 1 GHz with 17 IF bandwidths from 200 Hz to 50 MHz. It scanned and plotted signal strengths or could demodulate AM, FM and CW. This manual can be downloaded from the WJ & CEI Document Index page October 14, 2023 - The 1984 WJ Symposium report contained a paper by Bruce Long titled " Design Considerations for an Economical Compact Microwave Receiver ." Long was on the team developing the WJ-8969A (top picture at left), which was designed and built in Gaithersburg, MD. A later version, the WJ-8969C , was developed by WJ in San Jose, CA after the project was reassigned and yanked all the way across the country. This report can be downloaded from the WJ & CEI Document Index page September 16, 2023 - Nine new data sheets for a variety of interesting equipment. The DRO-50, a digital frequency display designed for the Hammarlund SP-600, the DRO-302A and DRO-302B frequency displays ,the DM-4 demodulator , which was heavily used by the NSA, the DMS-109, a tunable 5-1000 kHz LSB/USB demodulator with Collins mech filters and four demods in the DMS-105 series , all heavily used by the NSA. These data sheet can be downloaded from the WJ & CEI Document Index page August 30, 2023 - The data sheet for the WJ-8605 , a parallel input controlled variant of the Miniceptor is now available for download. It covers 20-512 MHz but options were limited. The preselector, CW, SSB, IFT and FE options cannot be installed in these radios. The IF filters were optimized for minimal ringing. It was identical the the WJ-8606 Miniceptor and both were sold only as circuitboard (BB= BreadBoard option). Both were designed around the fast synthesizer of the WJ-8607A which placed all of these radios under ITAR export restrictions. This data sheet can be downloaded from the WJ & CEI Document Index page May 23, 2023 - Watkins-Johnson made a wide array of equipment for demultiplexer FDM stacked telephone calls. The WJ-9518 was one of the first digitally tunable FDM demods . Some hobbyists stick a preamp in front of them and tune them to six different SSB HF frequencies they like to monitor. The WJ-9518E is the equalized version. These manuals can be downloaded from the WJ & CEI Document Index page March 5, 2023 - Paolo Viappiani with an interesting comparison and the competitive history of the venerable and popular Watkins-Johnson WJ-8711 and Ten-Tec RX-340. Also included are comparison and information on the no front panel versions of both lines, the WJ-8712 and the RX-331 . This fascinating article can be found via the Collector’s Corner or on the WJ & CEI Document Index page March 5, 2023 - A custom made handy front panel tester for the Watkins-Johnson Microprocessor Front Panel (MFP) of the WJ-8718/MFP and WJ-8716/MFP HF receivers. If you are troubleshooting the front panel for one of these fine radios, you’ll want to read this article even if you don’t built a complete tester. This article can be found via the Collector’s Corner or on the WJ & CEI Document Index page April 4, 2023 - A complete manual has been added for the DMS-107 and DMS-107A Signal Processors which tune 0.1 to 10 MHz in one band and demodulate AM, FM & CW with 8 different bandwidths. Two data sheets for these units have also been added, one form 1970 and one from 1973. These documents can be downloaded from the WJ & CEI Document Index page April 2, 2023 - The data sheet for the WJ 340A VLF receiver , which was mainly part of the RS-125 TEMPEST test set, but found many other uses as customers sought 19 different versions of this radio. This data sheet can be downloaded from the WJ & CEI Document Index page April 1, 2023 - A partial set of schematics for the WJ-8730 VHF/UHF receiver series with drop in tuners and plug-in IF strips and demodulators. Schematics for the WJ-9062 90-300 MHz tuner are included. These are photographic reproductions of the original diazo prints. These schematics can be downloaded from the WJ & CEI Document Index page March 26, 2023 - The indefatigable Paolo Viappani submitted four additional documents that will helpful to fans of the WJ-8718 series of HF receivers . A WJ-8718 series manual , an enhanced version of the WJ-8718 manual with 150 added pages of material, a revised version of the manual for the WJ-8718- 9, and a comparison of the rare Chinese rebuilt WJ-8718/MFP receivers with the stock Watkins-Johnson models. The manuals can be downloaded from the WJ & CEI Document Index page The Notes of on the Chinese rebuilt WJ-8718/MFP receivers can be found in the Collector Corner . January 27, 2023 - Seven catalog sections from the 2001 BAE - Gaithersburg catalog are now available for download. BAE briefly owned the Watkins-Johnson Gaithersburg operation and marketed many of the same products under the BAE name. These include: New Products Receivers Tuners DF Systems Signal Processing Wireless Accessories These catalog sections can be downloaded from the WJ & CEI Document Index page November 27, 2022 - Massive 1/2 GB upload of new Watkins-Johnson manuals. RS-160 surveillance system components: CSU-160 tuner switcher , HH-11 tuner for 2-30 MHz, VH-11 tuner for 30-60 MHz, VH-12 tuner for 60-120 MHz, VH-13 tuner for 100-180 MHz, UH-11 & UH-11-1 tuner for 250-500 MHz. Microwave receiver system components: Class C manual for 112 receiver , DM-112 & DM-112-1 demodulator , DM-112-5 (UK mods) demodulato r, MTF-100 & MTF-101 tuning frames , MTF-100A, MTF-101 & MTF-102 tuning frames , TH-120A tuner for 1-2 GHz, TH-145C tuner for 1-4.5 GHz, TH-145R tuner for 1-4.5 GHz, TH-240A tuner for 2-4 GHz, TH-480A tuner for 4-8 GHz, two different copies of manuals for the TH-480B & TH-480C tuners for 4-8 GHz, TH-480R tuner for 4-8 GHz, and the TH-812A tuner for 8-12 GHz. And a manual for the WJ-8718-9 HF receiver . Many thanks to Paolo Viappiani for the scans. These manuals can be downloaded from the WJ & CEI Document Index page November 27, 2002 - Data sheets are now available for the MTF-102A microwave tuning head frame , the TH-5 wideband 1-18 GHz tuning head and the TH series of tuning heads covering the TH-120R, TH-245R, TH-480R, TH-812R and TH-1218R microwave tuning heads . Many thanks to Paolo Viappiani for providing the scans. These data sheets can be downloaded from the WJ & CEI Document Index page October 10, 2022 - Manuals for the 112 and 112-1 microwave receivers and the DM-112 and DM112-1 demodulators are now available. Many thanks to Paolo Viappiani for these manuals. These manuals can be downloaded from the WJ & CEI Document Index page March 28, 2022 - Another Collector’s Corner article, this one from Paolo Viappiani delves deeply into the front panel control boards for the WJ-8716 and WJ-8718 series of radios to unravel the mystery of the MCM-2 board, as opposed to the more common MCM board (MCM is the Manual Control Module). This article can be found on the Collector Corner Page . January 23, 2022 - - In 2016, a chapter I wrote on the life of...