Why a 30M QRP CW Transmitter?
A friend, Bill Harbour, KD4PWB was enquiring about various aspects of the design of CW QRP transmitters. In particular, his interest centred around the amateur radio band of 30 metres (10.000 – 10.150 Mhz). Various topics and design principles had been previously discussed and in the end I decided to present an experimental transmitter for CW (morse code) QRP (low power less than 5W) for operation on the 30M amateur radio band. Bill’s original project revolved around a crystal oscillator using a TTL 7400 Quad 2-input NAND gate. The original project is described on Harry Lythall’s – SM0VPO pages. Bill has on hand some T37-6 toroids so we will try and use them but I will suggest other types. For our purposes, as a guide to demonstrate design principles, I decided to go back to basics and use a conventional crystal oscillator. Although in my pages on crystal oscillators I stress the need for a buffer amplifier I decided for sake of simplicity not to use one here (oh heresy!). Here is our
