Articles
Technical information
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Robert and Richard Santin - true ham heroes
When I was first licensed in the 1960s in Nebraska, two groups of hams were commonly heard on the air before those with jobs got off work - other teens like me and the disabled hams. Some of my earliest Novice ham buddies were blind students at the Nebraska School for the Blind in Nebraska City, and there were many other visually-impaired hams, all of whom were exceptional operators,... READ MORE |
ranickels 03/21/2022 |
Historic |
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Ceramic Loading Capacitor Replacement
Old style mica capacitors were used in the pi-net matching sections of several vintage transmitters and the combination of age, heat, and high RF currents have made them likely failure items. My Collins 32V-2 transmitter was to the point where it would not properly load to full power on 75 meters so something had to be done. Mica capacitors are no longer made but fortunately n... READ MORE |
ranickels 03/19/2022 |
Technical |
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Universal Frequency Converter
I found myself wanting to convert various frequencies to other frequencies and wanted a cheap and easy solution, so I designed a simple "universal converter" using the NE-602 and a programmable oscillator from Epson. I'd used the same combination in hundreds of "RANVerter" SDR Upconverter projects since my Dec. 2013 QST article and knew that while there were limitat... READ MORE |
ranickels 03/17/2022 |
Technical |
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Magnetic PCB holder
It's always a challenge to hold PC boards during assemly and testing. After purchasing a magnetic holder from Amazon I realized I wanted more and could easily make as many as I wanted using inexpensive 3 mm hardware from eBay and some strong "fridge magnets". All that's needed is to epoxy a standoff to the magnet - both tapped and threaded&nb... READ MORE |
ranickels 03/09/2022 |
Technical |
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Si5351 Quadrature Mode
The Si5351 has been the biggest boon to homebrewers since the invention of the NE-602, especially now that quartz crystals are essentially obsolete. But it's redundant to run the output of the 5351 through a johnson counter to develop the quadrature signals required for QSD/QSE SDR front-ends when there are three clock outputs available and the IC allows for phase offsets. &... READ MORE |
ranickels 03/09/2022 |
Technical |
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Some tips on the Johnson Pacemaker
It's pretty well accepted that the Pacemaker was not EF Johnson's finest effort. In fact it was the first of several failed attempts by the King of the AM Transmitters to make the transition to SSB. In the end, it was the rise of CB popularity that kept the company viable, along with its component business, while their ham business gradually faced away. ... READ MORE |
ranickels 03/03/2022 |
Technical |
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The William L. Howard Museum
LTC William L. Howard amassed a collection and in fact realized his dream of creating a museum that showcased the Army's technical intelligence operations - and a lot more. The following excerpt was written by Col. Howard and Todd KA1KAQ: William L Howard I first got interested in radio while a Cub Scout back in 1954... READ MORE |
ranickels 02/18/2022 |
Historic |
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Radio Belts
Some things you can improvise around, others - no way! And drive belts for radios are one of the latter, when one is broken or stretched to be unusable you need a new belt - but where to get it? Here's the answer: RADIO BELTS Many standard belts are shown but custom belts are no problem, just send them the information needed. A gr... READ MORE |
ranickels 02/14/2022 |
Technical |
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History of the Quartz Crystal Industry
Two excellent papers on the history of the quartz crystal industry. 1. A HISTORY OF THE QUARTZ CRYSTAL INDUSTRY IN THE USA With the aid of many of the people who were involved, this paper is an attempt to record the history of the quartz crystal industry in the USA. Although crystal units were in use at least a decade earlier, the beginning of the quartz crystal ind... READ MORE |
ranickels 02/11/2022 |
Historic |
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Adams-Morgan Co. radio parts catalog from 1915
Fascinating catalog from the "DigiKey of early radio" - the Adams Morgan Co. aka "AMCO" of Upper Montclair NJ. Download from the "Attachments" link below. ... READ MORE |
ranickels 02/02/2022 |
Historic |
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