NooElec RTL-SDR Antenna

[951ryan]

I am going to be mounting this on the roof which is why I think 50' won't be long enough. What kind of cable do you recommend for 100' lengths? The SCANNER ANT-BASE 30-1300MHZ 50'RG6 already comes with 50' of cables and I tried to match up the same specs.

The cable I bought was:
50ft RG6 (18AWG) 75Ohm, Quad Shield, CL2 Coaxial Cable with F Type Connector - White


My total build to connect to SDR is

http://www.amazon.com/dp/B001JT1KEG/
http://www.amazon.com/dp/B00HFYGQHU/
http://www.amazon.com/dp/B0090RGIKU/
http://www.monoprice.com/Product?c_id=102&cp_id=10216&cs_id=1021603&p_id=4061&seq=1&format=2

Praying I didn't miss anything.

 

[jonwienke]

Looks good overall. Isn't it ironic that the antenna and coax costs more than the radio?

 

[951ryan]

Agreed.

I plan on mounting to either my chimney or wooden balcony. What parts are need to build it like shown in the pic...

 

[jonwienke]

The antenna comes with the hardware needed to mount it to a mast. You'll need to supply the mast and whatever it attaches to.

 

[951ryan]

The antenna comes with the hardware needed to mount it to a mast. You'll need to supply the mast and whatever it attaches to.

So I'm thinking the 5' galvanized steel antenna mast with chimney mount and another 2' galvanized steel antenna mast for vertical separation like shown in the picture. What is that part called which connects the vertical and horizontal mast together?

 

[jonwienke]

A U-bolt. It comes with the antenna.

The horizontal piece is part of the antenna.

 

[Spleen]

Here's a good place to compare. If you aren't going to be doing much listening much above 450MHz, you can probably squeak by with the RG-6...

Coax Attenuation Chart

I am going to be mounting this on the roof which is why I think 50' won't be long enough. What kind of cable do you recommend for 100' lengths? The SCANNER ANT-BASE 30-1300MHZ 50'RG6 already comes with 50' of cables and I tried to match up the same specs.

The cable I bought was:
50ft RG6 (18AWG) 75Ohm, Quad Shield, CL2 Coaxial Cable with F Type Connector - White


My total build to connect to SDR is

Amazon.com: SCANNER ANT-BASE 30-1300MHZ 50'RG6 15ELM: Electronics
Amazon.com: Mediabridge F81 Connector - 3GHz Female to Female F-Type Adapter - 2 Pack: Electronics
Amazon.com: MCX Male to F Female Video Adapter: Everything Else
50ft RG6 (18AWG) 75Ohm, Quad Shield, CL2 Coaxial Cable with F Type Connector - White - Monoprice.com

Praying I didn't miss anything.

 

[951ryan]

Antenna and SDR adapters should be arriving tomorrow from Amazon. I got the mast tripod and 10' mast from Frys Electronics. I have a curbed tile roof and well pretty spooked about going up there decided my 2nd story balcony should be a good spot.

 

[popnokick]

Wow... that chimney in the last pic you posted just screams, "mount that mast on Me!". If you have permission to mount there and want to avoid going on the curved tile roof, can you get an extension ladder to place on the deck then lean up against the chimney? If you can, you could get to the highest point of the chimney... which is going to be much more effective from a "radio horizon" perspective. BUT... don't forget grounding. One nice thing about the tripod on the deck is that you can take it down/put it up in a reasonable time frame... and repeatedly if necessary. Sort of a portable antenna (as portable as an ST2 can be).

 

[951ryan]

I bought this indoor antenna (http://www.amazon.com/gp/product/B00HGHULFO) to attach to my SDR just to play with and wow it made a HUGE difference already. -23db to -3db with that cheapo antenna.

 

[Flatliner]

If you're comparing the new antenna with the one that comes with the TV dongle, then you certainly should expect an improvement. The supplied antenna is designed for UHF TV and is resonant at around 590 MHz (1.2:1 SWR) according to my analyser (possibly higher but my analyser only goes to 600 Mhz), and is pretty pants below that. You could make a free dipole antenna without using an antenna at all, using a piece of coax, and it will also perform better than what comes with the dongle.

Looking at your gain settings, you may get better results if you disable the RTL and Tuner AGC, turn the RF gain to 0 dB, then move it until the noise floor rises by around 10-15 dB. The S/N wont improve much after that, but you'll get a lot of overloading and image issues with what you have in that picture.

 

[951ryan]

I did as you suggested, seemed to help a bit. Im receiving the desired frequency loud and clear.

 

[Flatliner]

Having only an 8 bit ADC means that the dynamic range isn't so good, hence it's easily overloaded.

Your gain and PPM settings are almost the same as min now. Increasing the contrast a little, just so you can see weak signals will look a little better too.

You can get a lot of fun from an £8 dongle can't you!

 

[The777]

Help with settings

Hi, I guess my problem is the same as published in the forum, i have tried many settings but cannot hear anything, is there anything amiss? my settings are attached here, all help appreciated,

T777

 

[BM82557]

Hi, I guess my problem is the same as published in the forum, i have tried many settings but cannot hear anything, is there anything amiss? my settings are attached here, all help appreciated,

T777

127.9000 is AM mode, you have it set as NFM. Also increase the BANDWIDTH to 10000.

 

[rbm]

Hi, I guess my problem is the same as published in the forum, i have tried many settings but cannot hear anything, is there anything amiss? my settings are attached here, all help appreciated,

T777

That peak doesn't look like a 'real signal' to me.
(There doesn't appear to be any modulation on it.)

If you have any known, strong signals nearby, use that as a starting point.

Check the box marked 'Correct IQ' and see if it changes.

It may just be an 'artifact' created by the dongle.
Otherwise, most of your settings look ok. (other than the AM/FM thing and even then, you could hear 'something' in the wrong mode.)

By the way, if you have 'Noise Reduction' enabled and it's misadjusted, you may not hear anything at all.

Rich

Edit: I'd also recommend not tuning the peak to the very center of the display.
Slightly to one side or the other will give you a better indication.

 

[rbm]

Here's what 'Correct IQ' does.

These two dongles are tuned to the very same frequency.
They're attached to the very same antenna through 2-way splitter.

The top instance of SDR# has 'Correct IQ' selected.
The bottom instance does NOT.

Notice the BIG spike in the very center of the bottom display?
THAT is the artifact you may see wherever you tune to if 'Correct IQ' isn't checked.

Rich

SDRSharp Correct IQ

 

[Flatliner]

Hi, I guess my problem is the same as published in the forum, i have tried many settings but cannot hear anything, is there anything amiss? my settings are attached here, all help appreciated,

T777

Reduce the sample rate for now. There is no point pushing the dongle to its limit if you're not able to receive a signal properly.

Push the contrast up so we can see the other signals modulation history also.

Expand the Audio pane. If you cannot hear anything, then is the output set right i.e. to your speakers? However, as RBM has noted, that signal doesn't appear modulated. And 108-136 MHz is AM mode.

Can you receive anything, anywhere?