background preloader

N2BHA Ham Radio

Facebook Twitter

Ham Radio, Homebrew circuits and techniques, radio circuits, and electronics.

Tools, Parts, Kits for DIY'ers - Curious Inventor. ΔΔΔ   Tonne Software Homepage   ΔΔΔ. Analog/RF Design Resources - Circuit Sage. Quarter Century Wireless Association (QCWA) Founded 1947. NØJMY's Hayseed Hamfest. HAM RADIO - AMATEUR RADIO - HAM RADIO INFORMATION, LICENSE INFO!, PLANS - PROJECTS. The Real SWR Page - Explained by WC7I - Will high SWR burn up my radio?

High loss coax can really reduce your output power.

The Real SWR Page - Explained by WC7I - Will high SWR burn up my radio?

A coax with a 3 dB loss will suck up half the power, allowing the antenna to radiate the other half. End of part 1. Part 2 Antenna SWR Have you ever measured the SWR of a simple antenna? It should NOT have been 1:1 Lots of people think that a good antenna should have a 1:1 SWR as measured by an antenna analyzer. We need to look at what SWR means, and how an "antenna system" is different from a simple antenna. Unfortunately, we need some 6th grade mathematics for this explanation. One way to find SWR is to make a fraction of the coax and load impedance. SWR is really a simple fraction that puts the larger impedance in the top of the fraction, and the smaller impedance in the bottom of the fraction. It is done this way so the answer is always equal to, or greater than, 1. Let's try this to see what I mean.

SWR =72/50 = 1.44 which means the SWR is 1.44:1 Lets try this again using a 36 ohm vertical antenna with at least three un-grounded radials. Vintage Radio and Electronics. RadioSport. Memorial to G3YCC - QRP SITE. The QRP world heard of the passing of Frank G3YCC - who most know of from the masses of information he put at our disposal through his website.

Memorial to G3YCC - QRP SITE

Frank put a lot of time & effort into this and it would be a great pity if that work was lost. Permission to reproduce his site has been granted by Frank's wife who is pleased that he can be remembered in this way by the hobby he loved. The maintainer of the site, K3HRN, believes it should be a living work in progress as a tribute to Frank, and will make corrections and additions as occassion warrants. Please report any broken links, missing files, etc to K3HRN. Please be as specific as possible. Changes to Site 05/27/2005 Recovered Missing Files: The following files were found by Tony Fishpool G4WIF: PITANK.GIF - linked from oxo.htm ccsys.jpg - linked from ccsys.htm 05/30/2005 Updated SST Information: Updated Information for sst1.htm submitted by AL7FS Jim Larsen: April, 1997 through September, 2004 Powered By As Low as $3.49 per month. Electronics Demonstrations. Alpine Software - Alpine Software. Electronics.

Contents of Electronics section My Audio Sweep Generator Article from "Electronics World and Wireless World" My "Circuit Ideas" from "Electronics World and Wireless World" A few notes about 555 timers 3-phase sine-wave generator Mixers volts or Volts?


Amplifier power Amplifier clipping "RMS" watts Polarity and Phase Amplifer power vs supply voltage. Capacitor uF - nF - pF Conversion Chart. Capacitors and Resistors for Tube Electronics - JustRadios Capacitor uF - nF - pF Conversion Chart When reading schematics, repairing radios and buying capacitors, you often must convert between uF, nF and pF.

Capacitor uF - nF - pF Conversion Chart

Paper and electrolytic capacitors are usually expressed in terms of uF (microfarads). Short forms for micro farad includeuF, mfd, MFD, MF and UF. Mica capacitors are usually expressed in terms of pF (micromicrofarads) (picofarads). Hendricks QRP Kits - QRPKits. Ham radio. Chaîne de N2BHA. Education - Electronic Circuits. Tubes & Accessories. Welcome to - Learn Morse Code (CW) Online! - Learn CW Online. Surface Mount Soldering 101. DANS CLOSE OUTS AND SPECIAL DEALS. EVLA.html. Ham Radio Homebrew - Technical Reference: Homebrew. SolderSmoke Daily News. Make PCBs at home with magazine paper and your laser printer. How to make PCBs at home in 1 hour & W I T H O U T special materials What you need You need also: a blade cutter, scotch tape, sandpaper, kitchen paper, cotton wool, vice, hacksaw.

Make PCBs at home with magazine paper and your laser printer

How it works Laser printers and photocopiers use plastic toner, not ink, to draw images. Finding the right paper The perfect paper should be: glossy, thin, and cheap. Paper preparation I discard pages heavily printed, preferring pages with normal-size text on white background. Printer setup Laser printers are not designed for handling thin, cheap paper, so we must help them feeding the sheets manually instead of using the paper tray. Printing Disclaimer: your laser printer is not designed to handle this kind of paper. This is my PC thermometer circuit printed on IEN magazine paper. How to cut raw material PCB material is fibreglass like, and a trick to cut it effortlessly is to score a groove with a blade cutter or a glass cutter. Cleaning the board for transfer Preparing for transfer Iron it! Peeling The hanger tool . Web site of: kf4trd. K8ZT's Ham Radio Resources- QRP, DX, Logging, Contesting & Ham Radio. Almost All Digital Electronics. The American QRP Club.

Four States QRP Group. Ham Radio Association and Resources. GQRP Club - Low Power Amateur Radio. SDR.