pmr circuit diagram

PMR 446 external antenna - A slim jim PMR 446 Mhz antenna in spanish

Jpole for PMR-Radio - A 446 Mhz J-pole antenna

Antentop: Loop Antennas - Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

Building Coaxial Traps - This page describes the design and construction materials W8WWV used to build a coaxial cable trap. A coaxial cable trap is a parallel resonant circuit that is usually inserted in an antenna element to enable multiband operation.

Multi Band Antenna Traps - These devices are called Traps, but they are actually more like frequency sensitive switches. They are parallel resonant, high Q, tuned circuits which provide a very high impedance at their frequency of resonance.

Fun With Tubes - A noncommercial site operated by Max Robinson and dedicated to passing on and preserving knowledge of vacuum tube circuits and techniques.

Antique Radio Schematics and Capacitors for Tube Radios - Specializes in antique radio schematics and capacitors. carries antique radio schematic diagrams and electronic circuit service information for american, canadian and european antique radios.

Atwater Kent Home Page - This is a "techie" site, dedicated to presenting service manuals, parts lists, schematic diagrams and other information of value to restorers and technicians who try to keep these radios working

Canadian Antique Radios Schematics Diagrams Service - We specialize in canadian antique radio schematics for vintage tube radios made in canada. we carry lots of factory electronic circuit schematic diagrams as well as all rcc / radio college of canada service data 1920's - 70's.

E. H. Armstrong - Radio's premier inventor, Edwin H. Armstrong was responsible for the Regenerative Circuit (1912), the Superheterodyne Circuit (1918), the Superregenerative Circuit (1922) and the complete FM System (1933).

PSK31 Interfacing - PSK31 basics and radio to pc soundcard interface circuits, radio to soundcard, soundcard to radio and pc serial port to radio

Yaesu FT-847 (FT 847 FT847) at ham.dzm.ro - Yaesu FT-847 (FT 847 FT847) transceivers mods reviews software manuals and diagrams

Far Circuits - FAR Circuits is exclusively a manufacturer of Printed Circuit Boards for electronic projects that are used by the Amateur Radio and electronic hobby enthusiast.

ExpressPCB  ^updated - Free PCB software is a snap to learn and use. For the first time, designing circuit boards is simple for the beginner and efficient for the professional.

Ipox5 radio link system - Ipox5 is the freeware version of a commercial radio linking system, designed for amateur, nhw, emergency communications etc. It is optimised for mobile broadband and difficult IP links. It allows PC access, and up to 100 users on your link at one time. Usefull for multiple PMR446 use on very large sites. Works under Windows 98, XP, Vista, and Linux (under Wine)

AM-6154 FAA Amplifier circuit conversion - AM-6154 222MHz grid Conversion Information by N0UK

Homebrew HF Amp with 3CX3000F7 - Grounded grid triode HF linear amplifier with pictures and schematics diagrams by W2DTC. The amp design was for 160 80 40 and 20 meters

Medium Frequency Amplifier Circuits Compared - Mark Connelly, WA1ION article on Medium Frequency Amplifier Circuits in PDF format, include some RF amplifier schematics

Rotator Brake Delay and Protection Circuit - A rotator modification by W4ZT

NiCad battery charger - A basic nicad battery charger using a single medium power transistor.

A low cost UHF/VHF duplexer - Duplexers for dual band radio are usually high pass filter and low pass filter combined in the same box. This circuit is a design within a cost of US$10.

A Power Supply on the Cheap - Need a variable power supply that is short circuit protected and over voltage protected; Here is a good one that can be built cheap by VE3IVJ

External Keypad for FT-817 - An external keypad for FT-817(ND), for the serious portable/field-day contester/operator. Homebrew it with the free firmware and public circuit diagram. The circuit is very simple and takes power supply from the ACC port of the radio

Universal QRP Transmitter - Here's the homebrew Universal QRP transmitter adapted from work by Wes Hayward - W7ZOI. The circuit originally appeared in QRP Classics published in 1980 by the ARRL

Receiver block diagram - This is a block diagram of a superhetrodyne receiver.