Yagi Antenna 88-108 MHz

This antenna below is a construction of an Yagi antenna calculated for the FM broadcasting band 88 - 108 MHz. The central frequency used for 100MHz. You can extrapolate easily below for others frequency grace to values of diagrams. This antenna is less difficult to construct than the one presented on the previous page.DescriptionThe goal...

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Tunable Dipole Antenna For FM Broadcast

This is a simple dipole antenna for FM broadcast. It can be tune for 88-108 MHz frequency range. It's very clear and easy to build. For more gain it can be stacked (2 or 4 antennas and used power divider for distributing RF energy).How to construct:Solder all copper pieces before attaching to the 1/2[inch] plastic T.The aluminum tubing is...

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250W Power Amplifier with the BLF548 for 100 - 450 MHz

The BLF548 is a balanced N-channel enhancement mode vertical D-MOS transistor in a SOT262 package, especially designed for use in wideband amplifiers up to 500 MHz. The transistor is capable to deliver 150 W nominal output power at a supply voltage of 28 Volts. Due to the low output capacitance the attainable bandwidth will exceed 300 MHz.A...

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QRP Operating at Crater Lake National Park

After three weeks, 5300 miles and 12 western states Beth and I are back in Rochester. I took along my K1 in a lunch bag so that I'd be ready for any ham opportunities.One of our tourist stops was Crater Lake in southeastern Oregon. On August 19 I found a tree stump overlooking the lake, threw a 32' length of wire into a nearby tree and...

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An Arduino and RS485

I love being a student! It gives you tonnes of perks, such as free industrial samples from semiconductor companies. I just got my order of MAX485 ICs through the post this morning, so I've spent the day playing around with Arduino and RS485 comms. I'm now going to share my experiences with youThe aim of this demo is to simulate some serial...

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Arduino Backplane Experiment

Just as an experiment I thought I'd try this...My motivation:Pictured above is an Allen Bradley SLC-500 PLC. We use these a lot in work to automate industrial processes. They're very expensive, and all they are is a simple motherboard connecting daughter boards. The first slot is the CPU and does all the processing, and the rest of the cards...

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FM Stereo Encoder With RC4200 Multiplexer IC

This circuit is stereo encoder for stereo modulation fm broadcast. The Basic component for stereo multiplexing is a single RC4200 IC. The textbook way of processing and encoding a stereo signal for FM transmission goes like this:1) Take both channels and low-pass-filter them at 15kHz, with steep rolloff;2) Apply pre-emphasis. Depending on...

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iPhones are great things

Just spent £1.79 on an app to blog from my phone. Lets see how it goes...-- Post From My iPh...

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