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attenuator [2024/02/06 15:41] ei3jdbattenuator [2024/02/06 15:50] ei3jdb
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  * Connectors and wire (I bought a pigtail that had a BNC at one end and an SMA at the other, and an N-type chassis mount with an SMA on the back)  * Connectors and wire (I bought a pigtail that had a BNC at one end and an SMA at the other, and an N-type chassis mount with an SMA on the back)
  
- Box that can sink the heat (I bent some 50mm x 3mm aluminium strip into half a box -- another piece of aluminium sheet can make a lid.)+ Metal box that can sink the heat (I bent some 50mm x 3mm aluminium strip into half a box -- another piece of aluminium sheet can make a lid.) 
 + 
 +You will also need things like a soldering iron, drills, spanners and screwdrivers to fit the connectors, and some way of measuring RF impedance.  I used a NanoVNA but any RF source coupled with a SWR meter should also work.
  
 ==Construction== ==Construction==
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 +==Testing==
 +
 +Test that both the inputs produce the expected SWR measurements and impedance values (my NanoVNA said 49.something ohms and a few pF of capacitance in the 70cm band.) Also test that shorting out one port does not change the impedance values of the other by very much.
 +
 +If these tests pass, you have an attenuator.
  
  
attenuator.txt · Last modified: 2024/02/06 16:16 by ei3jdb