Best antenna for RTL2832U SDR

[debojitacharjee]

The ML30 loop antenna that has been mentioned will cover medium wave all the way into the SW spectrum. You also might want to do a google search a”broomstick” antenna. Normally designed for HF, it can be adapted to MW as well. It is basically what you are describing in your original post, but on a larger scale. Think of it as a loopstick antenna on steroids.

B.S.

I need to build one.

 

[debojitacharjee]

Copper wire loops need not take up a lot of area; that is simply not true. How about a plastic milk crate as the form?

How to build a Milk Crate AM Broadcast Loop Antenna

Many thanks to SWLing Post contributor, James Townley, who shares the following guest post originally posted on his Shortwave/Medium Wave blog: AM Broadcast Loop Antenna by James Townley Several ye…

swling.com

Mike

I need the formula and design concept.

 

[debojitacharjee]

I would like to build a loop antenna for receiving AM broadcasts (MW and SW).

Please tell me the formula and the method using a variable capacitor.

I would also like to know the difference between a simple loop antenna and a magnetic loop antenna. Which one is better for AM reception?

 

[Dirk_SDR]

AM and FM are modulation types, that can be used on nearly any frequency.
Antennas are mainly made for certain frequency ranges.
Do not use 2 antennas in parallel.

As PDXh0b0 said, you will need some or many antennas depending on your location and on what you want to receive.
So a discone and the RTL-SDR dipole antenna: Using our new Dipole Antenna Kit
... are a good wide band starting point.

 

[jeepsandradios]

Dont you already have a thread here ?

How to build a loop antenna?

I need to know how to calculate the number of turns and the diameter of a loop antenna to receive AM broadcast of 525–1705 kHz. Can a loop antenna be used to receive shortwave frequencies above 2.3 MHz?

forums.radioreference.com

 

[prcguy]

Why not try a big ferrite rod antenna for AM reception? I built one of these sticking two giant ferrite rods in some PVC pipe then winding the primary coil and secondary pickup loop and it really works great.

 

[ka3jjz]

Read the article. You need neither a formula nor really the design concept. This loop inductively couples to a portable radio, like many such loops (the Grundig AN200 and it's various clones do this as well).

Don't overthink - just build and enjoy

Mike

 

[TAC4]

That's quite an expensive antenna. Why should I buy it if I can build one?

Do you know the formula to build a loop antenna?

Yes I do, here is the link VK3CPU Magnetic Loop Antenna Calculator lol
We are literally going around in circles in this thread no
pun intended. I think the OP is playing us ? He also has
another loop thread started in the forum. I literally have
loop burn out now, thanks a lot lol. By the way OP you
never did mention what radio you are using ?

 

[dkcorlfla]

I have 14 different antennas outside for sdr
Tram 1410
Tram 1411
1/4 wave gp tuned to 402 mhz
1/4 wave gp tuned to 433 mhz
1/4 wave gp tuned to 915 mhz
1/4 wave gp tuned to 1090 mhz
1/4 wave gp with reflector for satcom
Patch antenna
Qfh tune to 137.5 mhz
V-dipole tuned to 137.5 mhz
J-pole tuned to 154 mhz
Ofc dipole
Hf dipole
K-180wla loop

Discones are great to find what you want to listen too, then you build an antenna to target your interest 😉

If you want to go above the sdr frequency range you'll need an down converter & appropriate antenna

I'm curious about the 1/4 ground plane you made for 433 and 915Mhz, do you see a noticeable improvement over the discone? If so I will have to make a pair of these.

Thanks, Dale

 

[debojitacharjee]

AM and FM are modulation types, that can be used on nearly any frequency.
Antennas are mainly made for certain frequency ranges.
Do not use 2 antennas in parallel.

As PDXh0b0 said, you will need some or many antennas depending on your location and on what you want to receive.
So a discone and the RTL-SDR dipole antenna: Using our new Dipole Antenna Kit
... are a good wide band starting point.

But how about using a simple loop or magnetic loop antenna? That can work on both AM and FM.

 

[debojitacharjee]

Dont you already have a thread here ?

How to build a loop antenna?

I need to know how to calculate the number of turns and the diameter of a loop antenna to receive AM broadcast of 525–1705 kHz. Can a loop antenna be used to receive shortwave frequencies above 2.3 MHz?

forums.radioreference.com

In that thread, I am not getting the formula and the design method.

 

[debojitacharjee]

Why not try a big ferrite rod antenna for AM reception? I built one of these sticking two giant ferrite rods in some PVC pipe then winding the primary coil and secondary pickup loop and it really works great.

But what is the formula for building it?

Is it going to work for MW and SW bands?

 

[debojitacharjee]

Yes I do, here is the link VK3CPU Magnetic Loop Antenna Calculator lol
We are literally going around in circles in this thread no
pun intended. I think the OP is playing us ? He also has
another loop thread started in the forum. I literally have
loop burn out now, thanks a lot lol. By the way OP you
never did mention what radio you are using ?

That seems like a magnetic loop antenna but I am looking for the formula for a simple loop antenna.

 

[prcguy]

But what is the formula for building it?

Is it going to work for MW and SW bands?

If the specific building info was not there it’s in another one of his videos, I found it and built two ferrite antennas. Like this and many similar projects you need a little test equipment to measure inductance of the loop or ferrite windings so you know where the antenna will resonate with a 365pf variable capacitor. It’s nearly impossible to build a tunable antenna without it and have it work in the frequency range you want.

Or just build an untuned shielded loop using large coax for the loop with a thin section of braid cut out at the top feeding a small 4:1 balun and preamp. Those work ok well and don’t require tuning or test equipment but you have to purchase a good low noise preamp.

 

[cg]

Exactly what and how far away are you trying receive? What can or can't you do in terms of outside antennas?
Virtually every antenna can receive that entire radio range if you are trying to monitor a 100 watt signal from a 100 foot tower 1/4 mile away over flat terrain.
Don't be afraid to experiment with some home built stuff on known signals.

 

[TAC4]

I am officially signing off from this thread lol. Tootdaloo

 

[majoco]

Me too.

 

[debojitacharjee]

If the specific building info was not there it’s in another one of his videos, I found it and built two ferrite antennas. Like this and many similar projects you need a little test equipment to measure inductance of the loop or ferrite windings so you know where the antenna will resonate with a 365pf variable capacitor. It’s nearly impossible to build a tunable antenna without it and have it work in the frequency range you want.

Or just build an untuned shielded loop using large coax for the loop with a thin section of braid cut out at the top feeding a small 4:1 balun and preamp. Those work ok well and don’t require tuning or test equipment but you have to purchase a good low noise preamp.

But this way it won't be a desirable antenna. I need the formula and design theory. I need to know the relation between the frequency range and the loop size. and turns.

 

[debojitacharjee]

Exactly what and how far away are you trying receive? What can or can't you do in terms of outside antennas?
Virtually every antenna can receive that entire radio range if you are trying to monitor a 100 watt signal from a 100 foot tower 1/4 mile away over flat terrain.
Don't be afraid to experiment with some home built stuff on known signals.

I need to build one for my use but need to know the formula. Do you know how to design a loop antenna using any formula?

 

[cg]

1. Go to Google
2. Type in " I want to build a loop antenna, ONLY a loop antenna, and I won't listen to what others suggest"
3. Ignore what Google suggests and keep asking the same question over and over again.