The NXP MRF101 series high ruggedness N-channel Enhancement-mode lateral MOSFETs promise over 100 Watt CW output power and slightly over 20 dB gain from 1.8 MHz all the way up to 250 MHz. Their mismatch insensitivity for a VSWR of greater than 65:1 without significant device degradation makes these devices extremely interesting for amateur radio […]
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Amateur Radio
ICS501 / ICS501 VHF Experiments
The ICS501 / ICS511 from Renesas are easy to use, fully integrated clock multipliers for output frequencies up to 200 MHz. What makes them particuarly interesting is the integrated crystal oscillator circuit and ability to produce some fractional multiples, such as 6.25 or 2.5. So let’s find out if they’re interesting for the hobbyist who […]
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Lumped-Element Wilkinson Splitter / Combiner Design
This is a supplemental article to two of my videos on my YouTube channel about the theory and design of Wilkinson splitters and combiners. A Wilkinson divider is a specific class of power divider with high isolation between the output ports. This feature is particularly useful when used as a combiner. This article will show […]
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Tiger / Rat Tail for Handheld Radios
Handheld radios are getting more and more sophisticated and versatile. The bottleneck for modern handheld radios is often the stock antenna. There is an extremely simple yet very effective add-on called a “Tiger Tail” or “Rat Tail” to remedy this situation. This article is going to explain how to make your own. For less than […]
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850 MHz Scanner Preamplifier / Filter Project
This article shows how to use off-the-shelf parts to improve the performance of a radio scanner in the 800 – 900 MHz band. Furthermore, it shows how to expand radio coverage by using two different receive antennas at the same time. For some reason, my new BCD996XT scanner wasn’t working as expected on the statewide […]
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