Time to make: 30 minutes
Cost: 5 USD
Cost: 5 USD
Can be made for many frequencies. Commonly used for higher frequencies from 80 MHz and upwards past 2.4 GHz. In this case, used for 433 MHz, where home automation usually is found. Copper is soldered, and the whole thing is put inside of glue to protect it. The connector used here is an F-connector, but you can use any. Look for a bulkhead-connector.
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