New video about impedance matching using an L-Network. This is a complimentary video to my classic text blog entry I wrote about this subject earlier.
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Search Results for: L network
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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Tektronix RSA 306 | GPS Receiver and Clock Reference
The Tektronix RSA 306 is a great low-cost USB 3.0 spectrum analyzer for up to 6 GHz in an ultra low-profile format. If paired with the RSA Map function of SignalVu-PC and a GPS receiver, it becomes an extremely powerful tool for interference hunting and signal strength mapping. This article shows a possible way to […]
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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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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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Crystal controlled listening device
There are tons of circuits for listening devices available on the internet. For the most part, they all have in common that they are virtually useless. This article shows how to build a reliable, small and inexpensive listening device using a PLL clock multiplier and a standard crystal. Most audio listening devices, also called spy […]
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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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