Build Your Own 4:1 BALUN With Coax

 Thank to Ralph Gable of "Electronics for the inquisitive experimenter" for this cheap and easy way to make a  basic 4:1 BALUN.

Ralph takes you step-by-step through the design and construction procedures.  Each step is thoroughly explained and demonstrated.

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Here are a few comments from Ralph:

In this video I am going to show you how to build a 4:1 BALUN using nothing but a length of coaxial cable. I will work through the process of design and construction one step at a time with many pictures to show you how I did it. More than that! I am going to explain WHY it works. I sourced a number of books and the Internet looking for this answer and I was amazed at how little there was out there. Well, not so here. I give you the explanation plain and simple with simple math. ** IMPORTANT NOTE ** At 14:30 I state that 28.79 inches = 78.13 cm. REALITY: 28.79 inches = 73.13 cm Ooops! Well, a 3 does look a lot like an 8. :-/ **Thanks to a viewer for the observant correction!** PROMISED SPEED OF LIGHT NUMBERS: C(in/sec) = 11802852677 in/sec C(cm/sec) = 29979245800 cm/sec Time Markers for Your Convenience ---------------------------- 00:05 Introductory Comments 01:08 The Basic Design 02:32 How does it work 07:37 Designing One 07:37 Gathering needed Information 09:14 Our Design - Information Gathered 11:12 Deciding on a Configuration 13:38 Our choice of configuration 13:57 Calculate the actual length of coax 14:42 Deciding on final Pigtail length 15:03 The Actual Build 15:10 Cutting the BALUN coax to length 15:25 Procuring a feedline 15:37 Cutting the Pigtails 16:07 Stripping the coax and pigtails 16:50 Tinning ALL conductors 17:07 Procure #24AWG wire for BALUN assembly 17:29 Arrange the coax for assembly 18:01 Connecting the shields together with wire 18:20 Soldering the shield connections 19:04 Connect the feedline to the BALUN coax 19:38 Adding the pigtails 19:41 The feedline/BALUN coax pigtail 19:56 The BALUN coax pigtail 20:04 Final Inspection before test 20:27 Testing & Adjustment 20:31 Initial Test with results 21:37 Weatherize your BALUN 22:02 Adjustment 23:20 FINAL TEST RESULTS 23:59 Lessons Learned: Experiment Debriefing 25:45 Final Comments and toodle-oots -----------------------------





Required Information


Cutting the feed line

Stripping the coax

Electronics for the Inquisitive Experimenter

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