RFSim99 is a free linear S-parameter based circuit simulator offering schematic capture, simulation, 1 port and 2 port S-parameter display and file support, tolerance analysis, stability circles, and much more. Requires Windows 95, 98, NT or 2000. File size 2045K

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Qucs is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit. After that simulation has finished you can view the simulation results on a presentation page or window.
Link to Qucs site

The following limitations apply to the EAGLE Light Edition in general:
•    The useable board area is limited to 100 x 80 mm (4 x 3.2 inches).
•    Only two signal layers can be used (Top and Bottom).
•    The schematic editor can only create one sheet.
Apart from these three limitiations the EAGLE Light Edition can do anything the Professional Edition can do. You can even load, view and print drawings that exceed these limits!
 Link Eagle Printed Circuit Freeware

This Application Note describes the performance of the Avago Technologies AT-41511 low cost low noise bipolar transistor. The AT-41511 is used in a two stage low noise amplifier in the 800 to 1000 MHz frequency range. The amplifier is designed around the catalog S Parameters at a VCE of 8 volts and a collector current, IC, of 10 mA. Although designed for operation at a VCE of 8 volts, the amplifier has very good performance as a low noise amplifier at collector voltages as low as 3 volts. The amplifier also provides a means of generating moderate power at a VCE of 5.5 volts.

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Coaxial Cable: RG_142_B/U

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Objectives
• 100 Watt HF transceiver
• Voice and CW capability
• Remote antenna selection
• Remote antenna aiming (for beams)

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Air Capacitors are designed specifically for RF applications, VHF through microwave, and have become the industry standard of excellence. High Q and temperature stability are a result of proper attention to geometry and choice of optimum materials.

Data Sheet  File size: 1.56MB

Homebrew outdoor antenna to 2.4 GHz band.

Antenna gain is comparable to panel antennas including the Freedom Antenna Set sold in Finland. Comparing is made simple by connecting antennas to same computer with Orinoco WLAN card and indicating results in Link Test of the Client Manager. My antenna has been found about 2 dB better gain than the Freedom antenna, which is specified as 12 dBi antenna. And prices ... Oh, I need not even mention this! In Europe there is a maximum allowable output power of 20 dBm (100 mW) because of the ETSI standard we use. While Orinoco "red" card is transmitting 8 dBm signal and my antenna gain is about 14 dBi there has to be only 2 dB cable and connector loss to keep output level below 20 dBm. The Orinoco Adapter Cable takes about 1 dB and H1000 antenna cable takes 2 dB/10m. So using 5 metres antenna cable there is no risk of exceeding the output power within the ETSI standard. This antenna can also be built without the Ring to decrease antenna gain if needed especially with very short antenna cable.