Making antenna for HF for SDRPlay plus balun?

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beamin

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So I have at my disposal:
500+ feet of 14ga wire
100-200 feet of coax with connectors to make shorter pieces longer
30 foot tall bamboo poles
1cmX3cmX1cm gray ferrite ring for balun
magnet wire for balun
2nd story window to SDR for antenna or coax out
Ground rod soon.

With my old set up I had a unun I bought off ebay 11:1 or 9:1 linked to coax to the radio and 60ish foot long wire that went out second story window into a tree.

I'm trying to make something here at the new house but I have no idea where to start.

Is there a way to upload pictures to this site? I would like to make plans and see what you guys think of them...
 

ka3jjz

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You are making us cave dwellers Hulk-level green with envy.

With all those components you could make several antennas - and indeed, many do, because different kinds of antennas can work differently on the same signal. One might not hear it well, while they other might have it very clearly.

Before you start sketching plans, let's answer a few questions. How much room have you got to work with? Are you looking to hear something from a particular part of the world? Are you interested in not just HF work, but also MW? Those bamboo poles might not be the best choice; any trees on your property?

We have lots of links in our wiki, but before we overwhelm you, let's get some direction. The basic inverted L is where many people start, and it's easy to construct...here's a nice intro article that will get you started (links are always in blue)

Basic HF Antennas - The RadioReference Wiki

Mike
 

n9mxq

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Two words, FAN DIPOLE.. if you can swing it..

Sent from my SM-G950U using Tapatalk
 

prcguy

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What mix is the ferrite ring? It sounds very small and probably not suitable for an HF balun.

For general purpose use I think a 9:1 balun with 50 to 100ft of wire outside away from the house and in the clear is a good start. I would also put a good 1:1 choke balun in the feedline where it exits the house to keep noise inside the house from traveling up the coax. There are much better antennas you can make but they would be for very specific frequencies.

If you ground anything check out NEC article 810, which is specific to antenna grounding.
prcguy
 

beamin

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What mix is the ferrite ring? It sounds very small and probably not suitable for an HF balun.

For general purpose use I think a 9:1 balun with 50 to 100ft of wire outside away from the house and in the clear is a good start. I would also put a good 1:1 choke balun in the feedline where it exits the house to keep noise inside the house from traveling up the coax. There are much better antennas you can make but they would be for very specific frequencies.

If you ground anything check out NEC article 810, which is specific to antenna grounding.
prcguy

I don't know what the ring is made out of but its 3-4 times bigger then the ring on my ebay balun.

So if I make a balun I would wind two wires around it. The coax end will have a ratio of 1 turn to wire end which is 9 times the turns. One turn doesn't sound like much coupling to the ring. Should I wire three turns on coax side and 27 turns on the wire side? One thing I am trying to figure out: Wire side has one end connected to 27 turn coil on the balun and the other side of the 27 turn coil connects to ground? The coax inner connects to one end of the 3 turn coil and the shield to the other? Do I ground the shield of the coax? If I put the balun at the top of the pole with a wire to another pole and the balun is sitting 30 feet high. What should I run down the pole for my ground wire? Just wire or should I use the inner conductor of the coax running from the balun 27 coil end down to a ground rod?

I haven't figured out what gets grounded. I kind of what to ground the balun AND ground the shield of feed coax but that seems like it wouldn't work too many ground points.
 
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