YT1DL homesite

About me

My name is Dusan Milovanovic, YT1DL. I am first time licensed back in 1989. My first license was "C" that gives me right to work from radio club station and use club's call YU1GTU.

Since twelve, I start to built simple detector receivers for medium wave band. Back in eighties MW was still active and full of local radio stations. Take 20m long wire as antenna, water plum as ground, germanium diode from old radio, handset from kids telephone toy, and, I was hooked.

Miracle of listening radio without a batteries, simple radio circuits, thrill of doing something that other kids can just dream. Now, I have two sons. When I start to talk about "good old times", older one (nine years old) just says: "What is wrong with you?! Anybody can just turn on the radio; you do not need to build it!".

Like my kids, great number of ham radio operators think same: by new Japan radio, turn it on and work. But, where is a thrill of doing something by yourself, making something from nothing? I just do not get it!

I do not want to say that everybody need to work with home made equipment (I have Icom radio) , but building some parts from time to time will give them full of joy. When you built your own radio or some equipment you will feel joy and satisfaction with every QSO you made with it.

On this pages I want to show how is possible to make whole line, from key to antenna, including digimodes and software definite radio for 40m band.

Essential part of system will be:

1. Software defined radio (SDR) QRP Transceiver (SSB, CW, DIGIMODE)
2. Electronic memory keyer
2. Digital MCU controlled DDS VFO (optional)
4. Inverted V coaxial antenna

First QRP

My first QSO made with low power was with ex.YU4EZC back in 1990. It must be QRPP. Transmitter was only christal controlled oscillator. Receiver was old Hammarlund SP600. You can check transmitter schematics at picture bellow. It can not be simplest. Christal was from TV set colorburst oscillator. Three 4,5V batteries, connected in serial, was used to power up transmitter. The key was improvised just for tests and i was very surprised when I got an answer to my CQ. I work with club's call sign YU1GTU/QRP at that time.