Watkins-Johnson &
Communication Electronics, Inc

November 14, 2024 - A rare manual for the FS-101 and FS-102 frequency synthesizers. These units were an important step forward in the development of microprocessor controlled synthesized radios. They accepted BCD input from a DEC PDP-11 computer to control the VH and UH series tuners in the RS-160 system.

This manual can be downloaded from the WJ & CEI Document Index page

November 13, 2024 - A partial manual with full schematics for the Communication Electronics, Inc 232 tunable filter. Essentially a 2-30 MHz triple conversion HF tuner. 1st IF is 60 MHz, 2nd IF is 10 MHz, third IF came in three variations, the 232 had a 20 kHz, the 232-1 had 15 kHz and the 232-2 had 25 kHz. This manual covers the 232-1 and 232-2 and probably everything you need to know about the plain 232. A data sheet for these unit produced after CEI was purchased by Watkins-Johnsons is also available.

This manual and/or the data sheet can be downloaded from the WJ & CEI Document Index page.

November 7, 2024 - The Watkins-Johnson Workmanship Standards Manual. Documents like these were common among companies that had exacting standards for construction techniques in the electronics industry. Anyone who has ever looked inside a Watkins-Johnson or Communication Electronics, Inc radio can see that their radios were built to the highest standards.

This is a higher resolution scan of a very similar document that has been removed from the document index page.

This manual can be downloaded from the WJ & CEI Document Index page. Look near the bottom under Misc Technical Information.

October 21, 2024 - New in the documents, a manual for the Communication Electronics, Inc 901-5 receiver, which also covers the 901-1 and the plain 901. This was the first VHF receiver designed and built after numerous staff left Nems-Clarke to found CEI. Many thanks to Ross Lahlum for providing this scan.

This manual can be downloaded from the WJ & CEI Document Index page

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) demodulator, 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

This article can be found on the Collector Corner Page.

January 23, 2022 - - In 2016, a chapter I wrote on the life of WJ founder Dick Johnson was published in the National Academy of Engineering's Memorial Tributes book series.

Dick Johnson partnered with Dean Watkins to form Watkins-Johnson in 1957. In 1967 they purchased Communication Electronics, Inc and financed the building of the Gaitherburg facility for their new division. Most of the radios covered on this website were made by this division.

Links to this chapter can be found on the My Publications page.

January 21, 2022 - A full scan of the (1988-1989 Watkins-Johnson RF and Microwave Components catalog has been buried on this site along time. It has been added to the master document index to make it easier to find.

Be sure to check out the data sheet for the WJ-G1, which contains a running joke on Phase of the Moon that persisted in the catalog over a number of years. (p. 421 or pdf p. 407)

This catalog can be downloaded from the WJ & CEI Document Index page

January 10, 2022 - A scan of a photocopied manual for the WJ-9188A-18, the companion signal monitor for the WJ-8716 & WJ-8718 series of receivers. Can be used with other receivers having a 455 kHz IF frequency. This manual is not suitable for troubleshooting the half rack width WJ-9188A which has completely different circuitry.

This manual can be downloaded from the WJ & CEI Document Index page

December 27, 2021 - Twelve data sheets have been added covering most of the 300 series of early radios that Communication Electronics, Inc designed and built prior to and shortly after their acquisition by Watkins-Johnson. These radios covered HF, LF, VLF and ELF.

These data sheets cover the 301A, 301A-1, 302, 351, 352, 353, 354, 355, 356, 357, 371A, 373A and 377A radios.

Many of these were wideband receivers intended for RFI testing, Tempest and subcarrier intercept. The notable except is the 357 which most often came with the narrow bandwidths one would expect for receivers in these frequency ranges. Not included is the developmental data sheet for the 358 receiver, which when finally developed was sold as the DMS-105 demodulator.

These data sheets can be downloaded from the WJ & CEI Document Index page

December 14, 2021 - Twelve data sheets have been added covering most of the 500 series of early radios that Communication Electronics, Inc designed and built prior to and shortly after their acquisition by Watkins-Johnson.

These data sheets cover the 501, 501A, 504, 504A, 519, 521A, 521A-1, 555, 560, 565A, 595 and 601A radios made with both CEI and WJ name plates.

The earliest versions of the 501 receiver had rounded meters like the pictures of the 701 and 901 and data sheets listed below. Meter and knob types changed unpredictably depending on the size of an order and the amount of inventory in stock. Other than initial radios being made with rounded meters and gray knobs, there is no linear sequence, no direct correlation between appearance and date of production.

These data sheets can be downloaded from the WJ & CEI Document Index page

December 13, 2021 - Ten data sheets have been added covering most of the early Communication Electronics, Inc 700 series of UHF receivers. These radios have excellent sensitivity, competitive with many modern radios and fare better than most SDRs, doing so with nuvistors and ceramic planar tubes.

Data sheets for the 701, 701A, 702, 702A, 704, 705, 725, 730A, 737, 770, 770A and 775-3 can be downloaded for free from the WJ & CEI Document Index page

December 11, 2021 - The addition of 8 data sheets covers 15 different radios from the 900 series of VHF receivers from the early, pre-Watkins-Johnson days of Communication Electronics, Inc.

Data sheets from the Bethesda plant are very rare as the company was only in the rented space above Community Auto Service for a little over three years starting in 1960. By 1963, they had broken ground on the new Rockville plant, which they outgrew in less than a decade but weren't able to expand until they Watkins-Johnson absorbed them and built the Gaitherburg plant.

Data sheets for the 901A, 901B, 903B, 904, 904A, 905, 905A, 906, 906A, 907, 952, 960B, 960B-2, 965 and 977 can be downloaded for free from the WJ & CEI Document Index page

December 7, 2021 - Fifty-four data sheets have been added to the document index page. These include WJ-8710A, WJ-8611, WJ-8653B, WJ-8664, WJ-8711A, WJ-8615P, WJ-8607, WJ-866X, WJ-8712A WJ-8621, WJ-866X/DAT, WJ-8712P, WJ-8629, WJ-8609A, WJ-971Y/485, WJ-8634, WJ-860X/TU WJ-871Y/DOS1, WJ-8635, WJ-9605, WJ-9904, WJ-871Y/MATX, WJ-9607, WJ-871Y/SEU, WJ-9902A WJ-8721, WJ-9903-3, WJ-8723, WJ-9908A, HF-1000A, WJ-9119, WJ-9128X, WJ-9488, WJ-9128/TTI WJ-8986A, WJ-8996-1, WJ-9881A, WJ-9887, WJ-8991, WJ-9012, WJ-9886, WJ-9896, WJ-9424, WJ-9548 WJ-9548-1, WJ-9497, WJ-9543, WJ-9168, WJ-9311, WJ-9312, WJ-9314, WJ-9135, S-9903E, WJ-9954

These data sheets can be downloaded from the WJ & CEI Document Index page

November 29, 2021 - The options appendices manual for the WJ-954x demodulator series. This includes, App A: ACT1 Activity Monitor, App B: CEPT CEPT Formatter, App C: AUD12 12 channel audio reconstruction, App D: FLX & FLX-1 Flexible Demodulator Options, App E: ACT2 Activity Monitor, App F; T1 T1 Output Formatter Option, App G: 422 RS-422 Renote Interface.

This manual is now available for download from the WJ & CEI Document Index page

November 28, 2021 - The WJ-8809A microwave receiving system extended the miniceptor concept into microwave reception. Covering 0.1 to 18.5 GHz in a small package with low power usage was quite an accomplishment in 1993.

The data sheet for this radio is now available for download from the WJ & CEI Document Index page

November 27, 2021 - The WJ-8969 microwave receiver came in three types. The WJ-8969 was designed and built in Gaithersburg. The project was then moved to San Jose which redesigned it as the WJ-8969B and WJ-8969C. Thee data sheets for all three versions of these radios have now been uploaded.

These data sheets can be downloaded for free from the WJ & CEI Document Index page

November 24, 2021 - The WJ-9548 demodulator was the last and best of a long line of demods made by WJ. Full of DSPs and uPs, it was available with many different options. Introduced in 1989, it did not appear in any catalog until 1997. After a trade show, engineers hooked a WJ-9548 to an antenna and, while tuning around on shortwave, realized the 9548 contained the nucleus of a potentially new kind of radio, a revelation that led to the WJ-8711.

The manual and data sheet are now available for download from the WJ & CEI Document Index page

November 9, 2021 - Here's a complete manual for the WJ-9026 and WJ-9028 VHF/UHF receivers, all 600+ pages in a huge file. A popular radio with 30-1000 MHz coverage including a spectrum display and digital frequency readout in a 3U package, the same form factor as the fabled RS-111. The WJ-9028 is a re-engineered version of the WJ-9026, primarily for higher intercept points. The FCC was a major customer. The WJ-9028 also sold in the Netherlands, Israel and as the WJ-8734 in Germany. This manual also may be of use for working on the WJ-8735, WJ-8736, WJ-8737 and WJ-8738 radios.

The manual is now available for download from the WJ & CEI Document Index page

October 29, 2021 - The NAV version of the WJ-8718 was made for the Navy and nomeclatured AN/URR-74. Two versions of the AN/URR-74(V)2 manual are available, a clean, quality scan from Feb 1982 donated by Rich McClung, WA6KNW and a newer but poorer scan from June 1983.

These are now available for download from the WJ & CEI Document Index page

October 28, 2021 - The WJ-8730 was a versatile series of receivers that could house any 2 of 6 available tuners and any 3 bandwidths from 10 available. The WJ-8730 and WJ-8731 are the most common among private hands, though some WJ-8732 and WJ-8733 are around. A contract version was also made for Ling-Temco-Vought/E-Systems under the numbers G175J and G175K with special tuners for 1-2 GHz and 2-4 GHz.

I've yet to see a manual for these radios, but I did locate a partial set of Diazo blueprint schematics of pretty decent quality.

These schematics are now available for download from the WJ & CEI Document Index page

October 16, 2021 - A manual for the unusual MP-101-5 meter panel. This meter attaches to the 21.4 MHz IF ouput of a receiver and allows for a variety of measurements on the signal. An unusual and rare item.

The manual is now available for download from the WJ & CEI Document Index page

October 3, 2021 - The SWP-125 switch panel was the main switch box in the RS-125 Tempest test station. It has many other uses as it is basically four coaxial switched with 8 position each. There is some other non-coaxial switching ganged onto one of the positions which you may find an alternate use for using the new posted manual.

The manual is now available for download from the WJ & CEI Document Index page

September 30, 2021 - The manuals for the WJ-8969 Microwave Receiving System. In three parts, the WJ-8969/IFC demodulator/controller, the WJ-8969/TU0145, WJ-89679/TU0412 and WJ-8969/TU0112 tuning units, and a collection of notes on troubleshooting these receiver from the WJ Bonn office.

These are now available for download from the WJ & CEI Document Index page

August 8, 2021 - Engineer's notes on the DSP programming for the WJ-8711 HF receiver. These are rough internal notes provided because they may provide insights into the design. They are not necessarily the programming found inside the manufactured receivers.
This is now available for download from the WJ & CEI Document Index page and can be found under "Application Notes & Misc Technical Memos."

July 9, 2021 - The full manual for the hybrid WJ-8611 HF/VHF/UHF receiver with the analog RF sections and digital IF and demods is now available for free thanks to an anonymous donor from the Black Radio community.

This is now available for download from the WJ & CEI Document Index page

July 5, 2021 - The data sheet for the WJ-8611 HF/VHF/UHF receiver is now available.

This is now available for download from the WJ & CEI Document Index page

June 29, 2021- A full scan of the manual for WJ-8870-1 manpack portable HF receiver. Many thanks to Peter Schroeter for this manual.

This is now available for download from the WJ & CEI Document Index page

June 19, 2021 - Two new data sheets. One for the WJ-8617B(X) VHF/UHF receivers from Sept 1991 when these receivers were more flexible because of the Motorola 8609 microprocessor (also known as S1 versions). And developmental data sheet for the WJ-8617B-17 HF/VHF/UHF receiver.

These are now available for download from the WJ & CEI Document Index page

May 30, 2021 - Six data sheets for desirable Watkins-Johnson radios are now in the documents section: Preliminary and final data sheets for the WJ-8700 HF receiver. A data sheet for the HF-1000, the only radio they ever manufactured for the commercial (ham and SWL) market. The later version WJ-8711A HF receiver from the period when WJ was briefly owned by Signia-IDT. Two data sheets for the scarce and very nice WJ-8712P HF receiver, which is a WJ-8711 in a much smaller package, both when they were owned by other companies, BAE and Signia-IDT.

These are now available for download from the WJ & CEI Document Index page

May 21, 2021 - Added five data sheets for receivers in the WJ-8718 family of which over 10,000 were manufactured. The WJ-8716, WJ-8718, WJ-8718A, WJ-8718/URR-74 and the AN/URR-74(V)2 (based on WJ-8718A.

These are now available for download from the WJ & CEI Document Index page

May 15, 2021 - The complete series of Watkins-Johnson Tech Notes are now permanently available for free download from the Internet Archive. Many thanks to Jim Fenton for the contribution and work to make this possible.

https://archive.org/details/watkinsjohnsontechnotes

May 6, 2021 - Factory manuals for the 1 Hz Tuning Option and the 10 Hz BFO Option in the WJ-8716 and WJ-8718 have thus far been unavailable. Paolo Viappiani sought to create these manuals from scratch and his draft manuals are big leap forward if you have these options.

These are now available for download from the WJ & CEI Document Index page

May 6, 2021 - Two new files for WJ-8716, WJ-8718 and MFP versions of these radios courtesy of Paolo Viappiani. 1) A WJ-8718/MFP troubleshooting guide, featuring corrections to the original WJ manuals and diagrams for easier trouibleshooting. 2) An updated field installation guide for the very desirable Microprocessor Front Panel (MFP) option into WJ-8716 and WJ-8718 radios.

These documents can be found in the Collector Corner link show at the top of the page.

March 22, 2021 - Five additional WJ-8718 and options manuals. Paolo Viappiani donated pdfs of five WJ-878 manuals. An enhanced manual for the rare WJ-8718-19, which extended the coverage of the stock WJ-8718 to 100 MHz and four options manuals, WJ-8718/232 for serial control ports, WJ-8718/488-2 for a GPIB control port, WJ-8718/COR for the Carrier On Relay option and WJ-8718/FSK for the Frequency Shift Keying option.

These are now available for download from the WJ & CEI Document Index page

March 21, 2021 - Revamped feature: Collector Corner. A place for articles written by collectors and hobbyists on how to do things with these radios, tips and techniques on repairing and/or improving them, and projects involving these radios. Go to Collector Corner via the link in the masthead.

This feature has existed since the start of the website but has been buried in the back pages.

November 29, 2020 - In the 1970s electronic assembly standards manuals were relatively common. I was trained to the NASA Workmanship Standards while working as a technican at the Space Science and Engineeering Center on the UW Madison campus. Here's the Watkins-Johnson Workmanship Standards Manual from 1978 which shows how to build high quality, long lasting, reliable electronic equipment.

This document is now available for download from the WJ & CEI Document Index page

June 29, 2020 - Carl McGowan, G0KPE, has given permission to distribute his Visual Basic program for controlling a WJ-8712 receiver. The program was written for Win 95 & 98, performs well on XP and is untested on Win 7 or Win 10.

A zip file of this software are now available for download from the WJ & CEI Document Index page

June 29, 2020 - Added an operators manual for the WJ-8718/MFP, a factory article on the WJ-8711 DSP Fundamentals and an article written by Paolo Viapianni on field installation of the preselector option on any version of the WJ-8718.

These are now available for download from the WJ & CEI Document Index page

June 28, 2020 - More software added, some written by hobbyists:
WJ-RCS32 - Updated version of RCS. Suitable for one or more WJ-860x, WJ-860xA, WJ-8609A, WJ-8611, WJ-8629, WJ-8634, WJ-8635, WJ-8654, WJ-871y, WJ-8721, WJ-9902, WJ-9903, WJ-9904 or WJ-9908. Will also display the spectrum from the WJ-9168 SDU. Steeper requirements of 486DX33 with 4 MB RAM and HD space and Windows 3.1 or 95. Windows 95 required for multiple receiver control. Manul included in the zip file.
WJ-8712 v1.0 - Hobbyist written control software for this HF receiver. Sorry I didn't keep accurate nores on who sent it to me.
WJ-8618B Labview control software via IEEE-488 - Another hobbyist written program that I didn't keep track of.
WJ-861x simple serial control - Written by Geoff Bunza AD7JP.
Zip files of this software are now available for download from the WJ & CEI Document Index page

June 28, 2020 - A nice addition of three Waktins-Johnson software programs, all very old, but may still useful for hobbyists:
PCSW - HF Receiver Control Software. Written for the WJ-871y series of receivers, including the HF-1000. This requires a minimum of a 386/25 PC with a whooping 4 MB of RAM and Windows 3.1.
RCS - Receiver Control Software. Usable with a variety of equipment. I was able to communicate with a WJ-9546 demodulator using this program.
MCS - Miniceptor Control Software. Originally written for the WJ-8607, WJ-8607A and WJ-8609, I've been told it works with other WJ digital receivers like the Microceptor.

Zip files of this software are now available for download from the WJ & CEI Document Index page

June 27, 2020 - Six additional manual appendices for the WJ-8607A Miniceptor receivers.
Appendix D - Amplified 21.4 MHz IF Out & 10 MHz Reference Oscillator options.
Appendix E - Digital Scan Output option.
Appendix I - MCS-1 Miniceptor Control Software v 5.0 (covers WJ-860x, WJ-8809, WJ-8654 & WJ-8700).
Appendix J - HPIL Interface option.
Appendix K - Calibration option (covers WJ-860x series).
Appendix L - 3GFE Frequency Exrtender options (covers WJ-860x series).
These are now available for download from the WJ & CEI Document Index page

June 26, 2020 - A reader inquiry brought the dearth of spectrum display manuals to my attention. The wonderful 3" x 1" CEI and WJ spectrum displays were awesome in the days before SDR radios. Three manuals have been added.

The SM-8421, which was designed as companions for the 357 receivers and DMS-105 demodulators with their 2 MHz IFs.

The SM-8510 & SM-8511, designed for use with the Collins 51S-1, and R-388 series with their 500 MHz IFs.

And the SM-8512 & SM-8513, designed for use with the Collins R-390 series and other radios using a 455 kHz IF.

These are now available for download from the WJ & CEI Document Index page

January 12, 2020 - A reader asked for the manual for the AN/URR-52A, which is identical to the RS-111-1B-7. There are only 2 core versions of the RS-111 and they divide at the RS-111-1B-12A. The manual for the RS-111-1B-12A has been on this site for a while. The addition of this new manual for the RS-111-1B-7/ AN/URR-52A means manuals covering all the core circuits for both types of RS-111 radios are now available. The scores of minor variations are predominantly small tweaks for specific customers. This manual can be downloaded from the WJ & CEI Document Index page

January 7, 2020 - Added EMC Test Applications of the WJ-8940B, a publication explaining how to use this radio for testing to MIL-STD-461, MIL-STD-462, FCC Part 15 and CISPR Publication 1-6. This can be downloaded from the WJ & CEI Document Index page

May 23, 2019 - - - BIG NEWS - - - Limited permission to post downloadable copies of some manuals has been obtained from Leonardo DRS, the present owners of what was once Watkins-Johnson Communication Electronics division.

The following manuals listed below are now available for download from the WJ & CEI Document Index page

CEI 501 receiver , CEI 521A receiver, CEI 560 receiver, CEI 566 receiver, CEI 701A receiver, CEI 702A receiver, CEI 775-3 receiver, CEI 904A receiver CEI 906A receiver, and CEI 906A-4 receiver

One of the most important products CEI every designed the RS-111-1B-12

WJ 340A receiver, WJ 487A-(x) receiver

June 5, 2018 - Just added the 844 page RF and Microwave Component Designers Handbook from 1988-1989 in response to many requests I get for component data.