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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Search Results for: l network design
L-Network impedance matching
Impedance matching is an everyday problem for RF circuit designers. The L-Network is one of the easiest lossless ways of matching a low source impedance to a higher load impedance. This article shows how they work and how to design them. Matching a transistor amplifier’s low output impedance with the higher impedance of an antenna […]
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Diplexer with integrated Bias-T (Triplexer) for QO-100 and X-band microwave reception using LNBs
This article shows how to build a simple Triplexer (Diplexer plus integrated DC Bias-T) for use with commercial TV LNBs for QO-100 or X-band microwave experiments. Introduction When using modified, commercial LNBs for reception of the QO-100 amateur radio satellite or X-band microwave experiments, it is necessary to pass a clock-reference signal, a DC supply […]
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VHF LDMOS Power Amplifier Experiments
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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Measuring filter response using a noise source
If you own a spectrum analyzer with tracking generator or, even better, a good vector network analyzer, measuring the frequency response of a filter is fairly easy. But there is one old approach using a noise source that can turn any oscilloscope with a FFT spectrum view into a useful tool for determining the frequency […]
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Review: Jackson Labs GPSTCXO Eval Board
Jackson Labs offers several different precision timing solutions. Among them are various GPS-disciplined oscillators. They sent me an evaluation board for one of their ultra small, low-cost GPSDO. So let’s check it out! The GPS-disciplined Oscillator (GPSDO) reviewed in this article is a state-of-the-art eval board from Jackson labs equipped with a high-performance GPS receiver, […]
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Manufacturers
Are you a manufacturer or distributor and you have a great product for me to review? Awesome, send it in! Just be aware of the fact that I do not do paid reviews, no exception. If you send your product in, I will review it and call it as I see it. This is really […]
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AOCJY1 series high stability OCXOs from Abracon
An Oven Controlled Crystal Oscillator (OCXO) is used wherever one needs a highly accurate and precise frequency reference. Abracon manufactures a series of affordable off-the-shelf OCXOs, which are due to their low price and outstanding performance particularly suitable for homebrew designs. Abracon’s AOCJY1 series offers various through-hole OCXOs with several possible frequencies between 10 MHz […]
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Exclusive OR (XOR) gate based phase detector
A phase detector generates a voltage proportional to the difference in phase between two signals. They are used in Phase-Locked-Loop (PLL) designs and PM / FM demodulator circuits. But how do they work? I promised in a previous blog article titled ‘No Tune NE602 / NE612 FM Demodulator’ that I would explain how a quadrature […]
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No Tune NE602 / NE612 FM Demodulator
FM demodulators have and always will be desired circuits. Many circuit designs use old and obsolete parts or appear to be too complicated for beginners. This design shows a very simple FM demodulator, a quadrature demodulator to be precise, for a 455 KHz IF using only a handful of parts and an NE602. The NE602 […]
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