{"id":103642,"date":"2021-04-26T16:01:37","date_gmt":"2021-04-26T16:01:37","guid":{"rendered":"https:\/\/www.snapwhole.com\/index.php\/building-the-heathkit-cr-1-crystal-radio-2\/"},"modified":"2023-01-17T01:05:10","modified_gmt":"2023-01-17T01:05:10","slug":"building-low-power-dummy-loads-for-qrp-operating","status":"publish","type":"page","link":"https:\/\/www.snapwhole.com\/index.php\/building-low-power-dummy-loads-for-qrp-operating\/","title":{"rendered":"Building Low Power Dummy Loads for QRP Operating"},"content":{"rendered":"\n

The process of building 3 QRP Dummy Loads<\/mark><\/p>\n\n\n\n

Return To Ham Radio Projects<\/a><\/d3><\/center>

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Building Low Power Dummy Loads for QRP Operating<\/strong><\/mark><\/p>\n\n\n\n

I have been building a few QRP oscillators, experimenting with the different types and configurations<\/p>\n\n\n\n

I need a few dummy loads to terminate the circuits when testing for frequency and power out, to simulate real world operating conditions<\/p>\n\n\n\n

I decided to build three dummy loads, and use three different configurations<\/p>\n\n\n\n

50 mw \u2013 an old arc-net 50 ohm terminator
1 watt \u2013 use 1 watt resisters on a BNC pigtail
2 watts \u2013 use 2 watt resistors on a BNC right angle connector salvaged from a wireless router<\/mark><\/p>\n\n\n\n

I ordered 1 watt and 2 watt resistors from Digi-key<\/p>\n\n\n\n

I had the heat shrink tubing, arc-net terminator, the BNC pigtail and BNC right angle connector in my junk box<\/p>\n\n\n\n

The only other items I needed were solder and a soldering iron<\/p>\n\n\n\n

The arc-net Terminator was ready to go, but was only good for extremely low power oscillators, but useful when building the first stage of oscillators<\/p>\n\n\n\n

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\"QRPp<\/a>
QRPp Dummy Load Installed on Oscillator<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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So I started assembling the parts for the 1 Watt and 2 Watt Dummy Loads<\/p>\n\n\n\n

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\"Parts<\/a>
Parts to Build 3 Dummy Loads<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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The BNC pig tail needs resistors soldered between the center wire and the shield<\/p>\n\n\n\n

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BNC Pig Tail, signal pin to shield Dummy Load<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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The bare wires could provide an RF burn if touched, so they need covered, and heat shrink tubing work well and look better than tape<\/p>\n\n\n\n

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1 Watt Dummy Load needs covered to prevent accidental Shock<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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\"The<\/a>
The heat shrink tubing installed on the 1 watt dummy load<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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The BNC right angle connection needs resistors soldered between the center spring and the base of the connection<\/p>\n\n\n\n

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\"2<\/a>
2 Watt Dummy Load Soldered<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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The spring was easy to solder, but soldering to the connection base required a lot heat to get a good solder joint<\/p>\n\n\n\n

The completed dummy load installed on a oscillator built in an Altoids Tin<\/p>\n\n\n\n

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\"The<\/a>
The completed dummy load installed on a oscillator built in an Altoids Tin<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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The 2 watt resistors were a little large and I did not have a large enough piece of heat shrink tube, so I used electrical tape instead<\/p>\n\n\n\n

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\"Using<\/a>
Using Electrical Tape as an Insulator for Dummy Load<\/figcaption><\/figure><\/div><\/div>\n\n\n\n
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This project\u2019s total time to complete was about 15 minutes, and I now have three different dummy loads to use while building small oscillators and low power radios<\/p>\n\n\n\n

Watch the Dummy Load Build Video<\/p>\n\n\n\n

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