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Author Topic: 1:1 Current Balun in Box  (Read 1861 times)

Offline Robot Matrix

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1:1 Current Balun in Box
« on: January 27, 2025, 0832 UTC »
This made a HUGE difference in my reception. Previously, I was using a TV balun because I didn't have anything else and it reduced noise. But, it was degrading everything the closer you got to 5 MHz. LW was worthless. Now,  I can get WWVB on  60 kHz and the Navy transmitters around 20 kHz as long as it's grounded.

Made from a plastic box from Walmart, and parts from Lowe's and Amazon, including a 43 mix toroid. Very light weight. Made for just reception.





Tomorrow,  I'm making a fan dipole-ish assembly for it, as currently I'm using uneven lengths of wire on each side. I'll share pics. 
EDIT: I tried the dipole and was still getting too much noise from the neighborhood. Will use later on the new property in the quiet country later. Opted for the loop (see other post)
« Last Edit: February 04, 2025, 2246 UTC by Robot Matrix »
eQSL: RobotMatrix@proton.me
NESDR Smart V5, Ham It Up upconverter v1.3, WEB-888 SDR, Inverted L Antenna 20' up and 30' over with adjustable base loading coil, and various other antennas to cover 1kHz-1+GHz. Unless otherwise noted, all signals or broadcasts are received at my QTH with my own gear.

Offline Charlie_Dont_Surf

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Re: 1:1 Current Balun in Box
« Reply #1 on: January 30, 2025, 2016 UTC »
As you have figured out, that cable TV balun is not going to work very well below ~50 MHz.
I don't STRETCH the truth.

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Offline Robot Matrix

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Re: 1:1 Current Balun in Box
« Reply #2 on: February 04, 2025, 0536 UTC »
As you have figured out, that cable TV balun is not going to work very well below ~50 MHz.

It was OK down to around 5MHz. Most TV stuff is rated for at least that low nowadays. Even then, I could get a decent chunk of the AM broadcast band.

But now, I built a loop and abandoned the dipole idea. It was just too noisy here. Loops are nice and quiet... and easier to change direction. I have another post on this.
eQSL: RobotMatrix@proton.me
NESDR Smart V5, Ham It Up upconverter v1.3, WEB-888 SDR, Inverted L Antenna 20' up and 30' over with adjustable base loading coil, and various other antennas to cover 1kHz-1+GHz. Unless otherwise noted, all signals or broadcasts are received at my QTH with my own gear.

 

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