RASON Projects Page

Designing Bipolar Transistor Audio PreAmps, Designing JFET Transistor Audio PreAmps, Designing Op Amp IC Audio PreAmps, Switching Regulator Basics, Using Transistors As Switches.

RASON Projects Page – Amateur Radio

  • 10 Amp, 13.8 Volt Power Supply
  • 12 Volt Gel Cell Charger
  • Thermal Fan Controller
  • Transistor Audio Amplifiers
  • 12 Volt Gel Cell Charger
  • Switching Regulator Basics


A Potpourri of Audio Amplifiers  By N1HFX

“I intentionally avoided the use of IC amplifiers to provide a real learning experience for audio amplifier design. Although many IC amplifiers provide excellent performance at low cost, we need to learn the basics first. I will address IC audio amplifiers in a future article.”

The Radio Amateur Society of Norwich
P.O. Box 329 – Norwich, Connecticut 06360

NE612 – Balanced mixer with Local Oscillator

I am designing a circuit that implements an AM radio circuit that ultilises the IC Double mixer and Oscillator NE612. I was just wondering whether there is any standard symbol for this kind of IC.

mail from CM

There is no standard symbol for NE612, just a square box. You have to make a custom part in the CAD software or see if someone has done that. check these links on info of NE612 circuit and symbol….

GM47: Simple 30m Band QRP CW-Transceive

The Rx mixer is followed by a IF stage featuring an NE592. The mixer’s balanced output is directly connected to the amplifier’s differential input, minimizing component count at this point.

Simple 30m Band QRP CW-Transceiver

Direct Conversion Receiver using NE612 for HF Bands

The NE612 is an integrated circuit which contains a balanced mixer with its own on-board local oscillator and voltage regulator. The mixer can provide up to 18dB of gain at 45 Mhz, and the local oscillator will operate up to 200 Mhz.

HF Transceiver using NE612

I would be working on the Transverter first, as with this, I could try out the 9Mhz SSB Module that I already have. I would be building the Transverter for the 14 Mhz band depending on the values from my DC Receiver project using the NE612 IC


Ham Shack of W5JGV – Ralph

My Start as a Ham – Ralph’s Story – “I suppose my interest in things electrical began when at a very young age I poked a metal hairpin into an electrical outlet. To this day, I vividly remember the amazing flash and bang that resulted! Of course, I wanted to know why that happened. It was a few years more before I learned to read, and found out about electricity.”

Ham Shack of W5JGV – Ralph

Ananth Notes- Thank god you survived to tell the story, this was a Jolt of a start. Very few people survive this. I would like to add …

All Mains Inlet Sockets should be Shuttered, so that such a thing does not happen again to any child again. Another Law, No Mains Socket should be less that 5 feet above the ground level.

Then we should all move to a 24V home voltage standard, Read more at my Tech blog..

EMerge Alliance – Safe Low-voltage Power

Then ralph has many projects with educative information. A RF Ammeter the Easy Way. A 400 Watt 60 Hertz Power Inverter. These are interesting to study.

Experimental KW HV Switching Power Supply

A KW Switch Mode Regulated High Voltage Power Supply

The design of switching supplies is a bit more involved than traditional “big iron” transformer power supplies. When taken step-by-step, however, it is quite possible for an amateur to design and build a working high power switching power supply. This article describes a high power, high voltage switch mode power supply designed to operate a KW level RF power amplifier.

Home brew Litz Wire

The Litz wire was fashioned by taking two parallel strands of #18 AWG wire about 115 feet long and twisting them together in a clockwise direction with an electric drill until the twisted wires had about two turns per inch. The twisted wire was then cut into four equal length and laid side by side.

Radiocalc – Convertisseur Radio Universel

Besides classical functions and dB conversions, RadioCalc includes a converter of Power to field strength commonly used for EMC/EMS test-set-up. Also impedance can be represented as a function of reflection coefficient (somehow like an electronic Smith-chart). This and many other functions are obtained by clicking into the arrow of the “Conversion off” window.

Radiocalc – Convertisseur Radio Universel

dB calc Radiocalc

Thanks to RadioCalc the different dB charts are obsolete by computing the ratios of Power (W) or Voltages (V) according to dB = 10*log(P2/P1) ou dB = 20*log(V2/V1).

Just for a trial : type 100/10 (or just 10) and push the dB button as the ‘W’ mode is chosen, the result will be 10 dB, then choose the ‘V’ mode by clicking in the V button (in the Quick dB window) push again dB, the result is now 20 dB.

From – Temcom – Consulting for test & measurement and electronics in France

(This was Earlier Radiocalc, i have now updated the link to the new site in France)

WB4HFN Amateur Radio Website

The vintage radio equipment from the R.L. Drake Company. Life before solid state devices,..vintage radio equipment from the Collins Radio Company. Featuring the “S” Line radio equipment from the 1960’s and 70’s era.

WB4HFN Amateur Radio Website

Antenna construction, digital communications, operating tips and practices to handling CATV interference

Amateur Radio And Resource Information

Heathkit Vintage Amateur Radio Equipment

One of the first all solid state radios produced by Heathkit Company in the mid 1970’s was the SB-104 Transceiver.

Homebrew Electronic Projects of Harry

Homebrew Electronic Projects of Harry

Harry’s Homebrew Homepages; a resource for radio, hamradio and electronics in general.

Harry Lythall – SM0VPO/G4VVJ.

Antenna projects, Receiver circuits, Transmitters circuits, AF / Amps circuits, Morse Code, PSU circuits, Useful circuits, EPROM circuits, RF Converters, Synthesizer circuits.

QRZ Ham Radio

QRZ was founded in 1992 by Fred Lloyd, AA7BQ as a spinoff of what was once called the “Callsign Project”, a cooperative effort designed to obtain and distribute FCC database tapes.

QRZ Ham Radio


Amateur Radio Station – N7JND

“I have been a licensed Ham Radio Operator since 1979. I enjoy chatting on Ham Radio everyday of my life. I have never grown tired of this wonderful hobby. It’s part of my everyday life. Radio in itself has been part of my whole life.

My other passion is playing the drums. I have been playing drums since 1974 and still enjoy gigging in and around the Tucson area. I have developed a drumming style that is solid and acurate.I play both acoustic and electric drums”