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Home Rigs Antenna Files The Shack Rig Accessories Test Equipment Portable Operating Miscellaneous My Beliefs Links	A $10 Resistor Decade Board  After fighting with using pots to set resistor values in circuits, I finally decided to build a resistor decade board.  The commercial versions are expensive, so of course I just had to make one.  Originally the "budget buster" on this project was the switches.  However, I found slide switches for $0.12 each at All Electronics (if you buy 100).  I also decided I could live with 5% resistors for my work.  Resistors are usually better than rated and in each pack of 10 I found several that were within 1% to 2%.  I also used 1/2 watt resistors since they are the same price as 1/4 watt. So, I bought 100 switches, and 10 of each resistor value.  The PC board is about 3" x 5" double sided board; I used a combination of routing and manhattan style construction.  And of course there is some wire and alligator clips involved.  All of the parts came to about $30 and I plan to build 3 of them, so the unit cost is about $10.  And I will still have a mess of resistors and switches left over.  This board will give you resistor values from 1 ohm to 10 meg in 1 ohm steps.   Parts list and schematic for one decade board is below.  Note that for the "4" values I used a "1.0" and "3.0" value in series since "4.0" values are not standard values. 3" x 5" PC Board 2 - 10 R 2 - 300 R 1 - 20K R 2 - 1M R 28 Slide Switches 1 - 20 R 2 - 1K R 2 - 30K R 1 - 2M R 2 - 1.0 R 2 - 30 R 1 - 2K R 2 - 100K R 2 - 3M R 1 - 2.0 R 2 - 100 R 2 - 3K R 1 - 200K R 2 - Alligator Clips 2 - 3.0 R 1 - 200 R 2 - 10K R 2 - 300K R Wire