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Homepage Archive - August 2024 (page 1)

See Page 1 | 2 | 3 | 4 | of the July 2024 homepage archives.

Wednesday the 7th

Precision Apparatus Company Test Equipment

Precision Apparatus Company Test Equipment, September 1962 Radio-Electronics - RF CafeAccording to common advertisements seen in electronics and mechanics type magazines in the 1940s, '50s, '60s, the two best ways to get the woman of your dreams is by ordering a Charles Atlas body building course, or, at least according to these Precision Apparatus Company promos, becoming an electronics technician. Whether it be Hogarth in a World War II Echophone ad or Pete in this Precision Apparatus Company ad, it seems techies get the girls. It appeared in a 1962 issue of Radio-Electronics magazine. I don't know at what point nerds began being shunned by the babes rather than being wowed by them. Here's another Precision Apparatus Company advertisement asserting the same message. Maybe at some point the tables will turn again...

Connectors for PC Boards

Connectors for PC Boards, October 1969 Electronics World - RF CafeHere is another in a collection of articles on printed circuit board technology that appeared in the October 1969 edition of Electronics World magazine. Amphenol has been making and driving the evolution of electrical cable, sockets, and connectors since 1932. I have seen their advertisements in many of my vintage electronics magazines, including this one that appeared in these Radio News issues from January and October 1945. A lot of the innovation was driven by military and aerospace quality, reliability, pin density, and weight requirements, and as is always the case, a lot of the benefit redounded to the commercial realm as well. Many of the connector types appearing in this article were still being used during the years I worked in the defense electronics business. During my time as...

British Army's High-Powered Laser Weapon

British Army's High-Powered Laser Weapon - RF Cafe"UK scientists and engineers have successfully fired a high powered laser energy weapon from a British Army combat vehicle for the first time. The ground-breaking test was conducted at Dstl's (Defence Science and Technology Laboratory) range in Porton Down. The laser weapon neutralised targets at distances in excess of 1km. As part of MoD's Land Laser Directed Energy Weapon (LDEW) Demonstrator programme, the laser was mounted on a British Army Wolfhound armoured vehicle for the tests. The technology is intended to be a low-cost, precise and powerful defence against aerial threats, such as drones..."

Electronic Geometry Quiz

Electronic Geometry Quiz, January 1965 Popular Electronics - RF CafeAll of these technology-related quizzes from my collection of vintage Popular Electronics magazines were created by Robert p. Balin, and range in difficulty from relatively easy to head scratchers (for typical test takers like myownself). Sometimes modern readers will be stumped by references to dated drawings and/or terms like vacuum tubes and CRTs (which are themselves vacuum tubes, of course). This Electronics Geometry Quiz might assign a Millennial handicap on item "E" if you spaz out over the picture because of your relative youth, but if you get the other nine correct, you'll get all ten by default...

RF & Electronics Symbols for Office™

RF & Electronics Schematic & Block Diagram Symbols for Office™ r2 - RF CafeIt was a lot of work, but I finally finished a version of the "RF & Electronics Schematic & Block Diagram Symbols"" that works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog, antenna, and other commonly used symbols for system block diagrams and schematics created for Visio™. Each of the 1,000+ symbols was exported individually from Visio in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down without becoming pixelated, so all the shapes can be resized in a document and still look good. The imported symbols can also be UnGrouped into their original constituent parts for editing...

Tuesday the 6th

News Briefs

News Briefs, September 1968 Radio-Electronics - RF CafeThe Sperry Univac 1219 computer was one of the first transistorized mainframe computers. The 18-bit computer was used by the military for defense radars. As was the TPX-42 IFF synthetic radar I worked on in the USAF, the Univac 1219 consisted of chassis filled with plug-in printed and wire-wrapped circuit boards containing thousands of integrated circuits in DIP format. It also used magnetic core memory which handled up to 288, 18-bit words. As reported in this 1968 issue of Radio-Electronics magazine, two Univac 1219's powered the airport radar system which used a 9' x 12' composite array of CRT displays to project air traffic. Also, the FTC (Federal Trade Commission) issued a policy prohibiting companies from inflating the performance of transistorized products...

DIY Radio Chassis Work Fixture

Radio Chassis Work Fixture: Kirt's Cogitations™ #362 - RF CafeRF Cafe website visitor and frequent contributor Bob Davis just sent me a photo of an amazingly nice fixture he made for conveniently holding a radio chassis while being worked on. When I asked him if I could post it on the website, he prepared the construction info and additional photos shown below. He even provided links for purchasing the components! The first inhabitant of Bob's new radio chassis work fixture was his Zenith Model 6S511 superheterodyne, 6-tube AM broadcast / shortwave radio. It came out in 1941, which means it was one of the last new radio models manufactured until the end of World War II (1945), since radio companies were required to dedicate facilities for...

Electronics-Themed Comics

Electronics-Themed Comics, September 1969 Electronics World - RF CafeThese two tech-themed comics from the September 1969 issue of Electronics World magazine are pretty good. I especially like the one where the guy's wife entered his printed circuit board layout in an art contest. PCBs were just starting to gain momentum in production electronics as they replaced the old point-to-point wiring method. Also popular in that era was high fidelity stereo equipment. Owning a system with speakers that operated from 1 Hz through 30 to 40 kHz was major evidence of an audiophile's technical savvy, even though the human ear con only detect frequencies in the 30 Hz to 20 kHz range. Dogs can hear frequencies up into the 45 kHz range...

Battery-Free Power for Electronic Devices with Ambient RF

Battery-Free Power for Electronic Devices with Ambient RF - RF CafeThis is new? "Ubiquitous wireless technologies like Wi-Fi, Bluetooth, and 5G rely on radio frequency (RF) signals to send and receive data. A new prototype of an energy harvesting module—developed by a team led by scientists from the National University of Singapore (NUS) - can now convert ambient or 'waste' RF signals into direct current (DC) voltage. This can be used to power small electronic devices without the use of batteries. RF energy harvesting technologies, such as this, are essential as they reduce battery dependency, extend device lifetimes, minimize environmental impact, and enhance the feasibility of wireless sensor..."

Communications Satellites - Key to World-Wide TV

Communications Satellites - Key to World-Wide TV, March 1960 Popular Electronics - RF CafeIn 1960 when this article appeared in Popular Electronics magazine, futurists were predicting that within 10 years it would be possible to beam television signals between continents and directly into homes. It was the eve of Project Echo, which boosted a 100-foot-diameter inflatable metallized plastic ball into low Earth orbit to reflect signals efficiently back through the atmosphere. Engineers and scientists were already planning the next best thing - a satellite that not only reflected, but also amplified, possibly frequency converted, and would even steer signals that impinge upon it. Envisioned in this article is hundreds of satellites being available for relaying signals between all regions of the Earth on then-standard VHF channels. We now have successful...

RF Cascade Workbook

RF Cascade Workbook - RF Cafe RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running series, RF Cascade Workbook. Chances are you have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system cascade parameter and frequency planner that includes filters and mixers for a mere $45. Built in MS Excel, using RF Cascade Workbook is a cinch and the format is entirely customizable. It is significantly easier and faster than using a multi-thousand dollar simulator when a high level system analysis is all that is needed...

Monday the 5th

Unijunction Transistor Applications

20 Unijunction Transistor Applications, June 1968 Radio-Electronics - RF CafeUnijunction transistors (UJT) were relatively new semiconductor devices in 1968 when this article appeared in Radio-Electronics magazine. Of course for that matter most semiconductor devices were still relatively new then. Some commercial products were still being made with vacuum tubes. The "transistor" part of the name is somewhat of a misnomer due to its physical construction, in that there is no rectifying PN junction between the two bases, only a single PN junction (emitter) embedded part-way into the channel between the device's two "base" connections. There is no collector. The UJT is sometimes referred to as a double-based diode, although there is no PN junction separating the two base connections. It usefulness lies primarily in a negative resistance region...

The Iconoscope

The Iconoscope, July 1944 QST - RF CafeAn iconoscope was an early form of television image capturing tube. Some amateur radio operators were experimenting with slow scan TV even back when the technology was relatively new to the world. When this article was written in 1944, there were still large portions of the United States that did not have television broadcast coverage. Of course I would argue that at the time of my growing up in the 1960s and early 1970s a lot of areas - even suburbs - were still not covered by TV signals, based on how cruddy the reception at my parents' house was. But I digress. The article mentions that because of the lack of TV coverage, many amateurs did not even have television...

GaN-on-Silicon Fully Vertical Electronics

GaN-on-Silicon Fully Vertical Electronics - RF Cafe"École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland claims the first demonstration of direct growth of gallium nitride (GaN) at high temperature on silicon (Si) substrates simply by using a trimethyl-aluminium (TMAl) preflow, without any intentional AlN buffer. Among the benefits of the process could be the realization of 'more efficient fully vertical GaN-on-Si devices, in which the silicon substrate may become a functional part of the device, as well as novel devices that require effective current conduction to the substrate,' according to the team. Vertical current flow diode/transistor devices are particularly sought for power electronics, and the GaN/Si combination..."

Dry Process for Making PC Boards

Dry Process for Making PC Boards, October 1969 Electronics World - RF CafeThe October 1969 issue of Electronics World magazine contained no fewer than nine separate articles on the relatively new technology of printed circuit boards (PCBs). Through the mid 1960s, many, if not most, electronic assemblies used all point-to-point wiring connections, or a majority of point-to-point with a minor circuit or two on a PCB. Multilayer PCBs were being routinely manufactured for defense and aerospace applications, but more than two or three layers was a rarity in an AM/FM radio, television, or smart appliance (just kidding about the last one). This "dry process" for PCBs, costing $6k ($41k in 2017 dollars), was pitched as a low cost method for manufacturing small volume boards...

Many Thanks to Axiom Test Equipment for Continued Support!

Axiom Test Equipment - RF CafeAxiom Test Equipment, a Transcat company, allows you to rent or buy test equipment, repair test equipment, or sell or trade test equipment. They are committed to providing superior customer service and high quality electronic test equipment. Axiom offers customers several practical, efficient, and cost effective solutions for their projects' TE needs and is committed to providing superior customer service and high quality electronic test equipment. For anyone seeking a way to offload surplus or obsolete equipment, they offer a trade-in program or they will buy the equipment from you. Some vintage items are available fully calibrated. Please check out Axiom Test Equipment today - and don't miss the blog articles!

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks, and more. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Friday the 2nd

Electronics-Themed Comics

Electronics-Themed Comics, October 1960 Radio-Electronics - RF CafeWind down your workweek with this triplet of electronics-related comics from a 1960 issue of Radio-Electronics magazine. There are still plenty of us around who understand the page 78 comic. We are the generation(s) who sometimes needed to reach around to the back of the TV set and twist the vertical hold potentiometer to get the picture to stop climbing up or down the screen. The incredible feature of the comic is that the frame split appears to show the upper half of a man and the lower half of a woman in the same frame. Because of the structure and processing of the video signal signal, it would not have been due to parts of two noncontiguous frames or two separate channels. If you don't understand what I'm saying, it's because you weren't "there." Out of morbid curiosity...

The "Coherer"

The "Coherer", May 1967 Popular Electronics - RF CafeBefore there were vacuum tube and semiconductor diodes for use as RF signal detectors, there was the coherer. This article by Henry Davis in the May 1967 Popular Electronics magazine discusses the invention of the coherer by Dr. Edouard Branley. Dr. Branley's work was, as is often the case for the ultimate inventors of a new apparatus or process, based on predecessors who over time pieced together the puzzle of electromagnetic energy and its effects on objects located some distance from the source. Coherers rely on relatively strong, broadband energy like that emitted from the early spark gap transmitters in order to function; both being extremely crude methods compared to modern techniques...

1000x Faster Space Communications with Laser

1000x Faster Space Communications with Laser - RF Cafe""The University of Western Australia's TeraNet, a network of optical ground stations specializing in high-speed space communications, has successfully received laser signals from a German satellite in low Earth orbit. This breakthrough paves the way for a 1,000-fold increase in communication bandwidth between space and Earth. TeraNet's laser communication test with OSIRISv1 marks a step towards replacing outdated radio systems with high-speed lasers for space communications in Western Australia..."

Engineering & Tech Headlines <Archives>

• Canada Steps up Semiconductor Investment

ARRL on The Weather Channel

• GlobalWafers Gets $400M Chips Act Subsidy

• Silicon 100: Startups Worth Watching in 2024

PCs Have 2nd Quarter of Growth

Beads Block Noise

Beads Block Noise, April 1969 Electronics World - RF CafeThe April 1969 issue of Electronics World magazine included a large number of articles on the topic of filter design and use. Included were titles such as "LC Filters," "Practical Operating Limits for Filters," "Filters for Microwave," "Crystal Filters," and others which were contributed by experts in the field from industry and academia. Check the table of contents to see which ones have been posted here. This piece on the use of ferrite beads for blocking RF signals is more of a sidebar note than an article, but it's still worthy of inclusion. Ferrite beads and toroids are still widely employed for stopping radio frequency interference (RFI) on everything from AC...

Thanks to Anritsu for Their Support!

Anritsu (electronics test equipment) - RF CafeAnritsu has been a global provider of innovative communications test and measurement solutions for more than 120 years. Anritsu manufactures a full line of innovative components and accessories for RF and Microwave Test and Measurement Equipment including attenuators & terminations; coaxial cables, connectors & adapters; o-scopes; power meters & sensors; signal generators; antenna, signal, spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth & WLAN testers; PIM testers; amplifiers; power dividers; antennas. "We've Got You Covered."

Promote Your Company on RF Cafe

Sponsor RF Cafe for as Little as $40 per Month - RF CafeBanner Ads are rotated in all locations on the page! RF Cafe typically receives 8,000-15,000 visits each weekday. RF Cafe is a favorite of engineers, technicians, hobbyists, and students all over the world. With more than 17,000 pages in the Google search index, RF Cafe returns in favorable positions on many types of key searches, both for text and images. Your Banner Ads are displayed on average0,000 times per year! New content is added on a daily basis, which keeps the major search engines interested enough to spider it multiple times each day. Items added on the homepage often can be found in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the place to be...

Thursday the 1st

Universal Replacement Parts Kit

Universal Replacement Parts Kit from Standard Kollsman Industries, October 1961 Radio-Electronics - RF CafeField service of electronic products like radios, televisions, and even tape recorders/players and phonographs, was still a common thing in 1961 when this promotion appeared in Radio-Electronics magazine. Those assemblies had a lot of parts, most of which no two were the same. That is the nature of analog circuits containing multiple stages of varying gains, frequencies, and voltage / current / power levels. Stocking and carrying a kit of replacement parts likely to be exact replacements or suitable substitutes for factory parts was imperative for efficient and profitable business. Many component companies were supplying kits like this one featuring coils (inductors) for TV tuners from Standard Kollsman Industries. Similar kits existed for resistors, capacitors, vacuum tubes, transformers, dial lamps, switches, mechanical hardware, etc...

Many Thanks to Exodus Advanced Communications for Their Support

Exodus Advanced Communications - RF CafeExodus Advanced Communications is a multinational RF communication equipment and engineering service company serving both commercial and government entities and their affiliates worldwide. Power amplifiers ranging from 10 kHz to 51 GHz with various output power levels and noise figure ranges, we fully support custom designs and manufacturing requirements for both small and large volume levels. decades of combined experience in the RF field for numerous applications including military jamming, communications, radar, EMI/EMC and various commercial projects with all designing and manufacturing of our HPA, MPA, and LNA products in-house.

Experiment with Digital Readouts

Experiment with Digital Readouts, August 1969 Radio-Electronics - RF CafeYou might have heard of Pixie tubes and Nixie tubes from the era preceding light emitting diodes (LED's), but how about Elfin tubes? They were considered the next stage in the evolution of digital display devices. This article from a 1969 issue of Radio-Electronics magazine provides an introduction to Elfin tubes. The images above are from a listing on eBay offering to sell MG-19B Elfin Readout tubes for $10 each, in case you want one for a conversation piece or for a project. Elfin tubes are fairly accessible if this guy depletes his supply. I grabbed a shot of the tube and datasheet in case they disappear someday...

Werbel 2-Way Resistive Power Splitter for DC-7.2 GHz

Werbel Microwave 2-Way Resistive Power Splitter for DC to 7.2 GHz - RF CafeWerbel Microwave's WMRD02-7.2-S is a 2-way resistive power splitter / combiner that covers from DC to 7.2 GHz with ultra-wide bandwidth. This unique design accomplishes extremely flat frequency response in a small radial package. Our unique design approach provides higher than expected isolation between outputs at far ports than would be achieved in a typical star topology. It has applications in markets such as CATV, test and measurement, and military radio. Its small size makes it easy to integrate into compact systems. Designed, assembled, and tested in the USA.

Mac's Service Shop: Electric Shock

Mac's Service Shop: Electric Shock, August 1969 Electronics World - RF CafeUh-oh, I'd better issue a sensitivity warning before going on, because this 1969 Electronics World magazine article reports on electrocution data gathered via empirical testing that demonstrates a difference between men and women, especially since men fared better. Charles Dalziel, inventor of the ground fault interrupter (GFI) circuit, subjected men and women to increasing electrical current levels to determine how much each could take and still be able to release the small wire carrying the shocking current to their hands. The average "let-go current" was found to be 16 mA for men and 10.5 mA for women. Clearly sexism is present somewhere...

RF & Electronics Stencils for Visio

RF & Electronics stencils for Visio r4 - RF CafeWith more than 1000 custom-built stencils, this has got to be the most comprehensive set of Visio Stencils available for RF, analog, and digital system and schematic drawings! Every stencil symbol has been built to fit proportionally on the included A-, B-, and C-size drawing page templates (or use your own page if preferred). Components are provided for system block diagrams, conceptual drawings, schematics, test equipment, racks, and more. Page templates are provided with a preset scale (changeable) for a good presentation that can incorporate all provided symbols...

Many Thanks to ISOTEC for Continued Support!

ISOTEC Corporation - RF CafeSince 1996, ISOTEC has designed, developed and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components and filters for wireless service providers including non-magnetic connectors for quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM RF connectors components such as power dividers and directional couplers. Off-the-shelf and customized products up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and high-performance. Designs that are cost effective practical and repeatable.

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

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- Christmas-themed items

Anritsu Test Equipment - RF Cafe
Exodus Advanced Communications Best in Class RF Amplifier SSPAs

Axiom Test Equipment - RF Cafe