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Calibrated noise source - W0IYH
Information To Support Radcom Article "The Measurement of Noise" by Dave Roberts G8KBB Jan 2007
Hi Chaps. Enclosed in a Zip file for downloading are the following:
1. Copy of original article from QST (also reproduced in ARRL handbook for last few years)
2. Copy of datasheet on noise diode
3. Copy of datasheet on relay
4. Circuit diagram of proposed board
5. PCB layout showing PCB overlaid on standard diecast box
6. Bill of Materials (excludes box)
7. Spreadsheet showing stock numbers from Digikey and APPROXIMATE prices
Printed Circuit Board
The PCB is simple but in the interests of ease I propose to put 6 on 1 PCB and get it done as a prototype via George's friendly manufacturer as a good quality board. It is designed to fit into a standard 92x38x27 diecast box but you may want to do otherwise. The PCB output connection is deliberately long so that it can be cut down to fit different connector styles. It is a 50 ohm microstripline to avoid discontinuities assuming εr of FR4, 62 thou laminate and 2 oz copper.