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Author Topic: New, Experimental WebSDR available  (Read 7226 times)
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steve_qix
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« on: September 28, 2018, 11:41:20 PM »

I have been fooling around with a WebSDR setup, and I have it up and running (after quite a bit of work - wow).

Anyway, currently it's 75-80 meters only - hooked to my main antenna in a very quiet location.  If it works out, I'll add some other dongles for other bands, probably 160 meters.

So, it seems to be working quite well.  I was also able to bring it up on my phone, which is kind of nice !

I'll be making improvements as time goes by.

The site is here:  http://websdr.radioassociates.com:8901
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VE3ELQ
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« Reply #1 on: September 29, 2018, 07:44:34 AM »

Very cool Steve, tried it this AM tuning around a bit.  Noticed a record feature which is very valuable for checking own signal quality.  Will be using it for my projects.  Great job and thanks.

73s  Nigel
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steve_qix
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« Reply #2 on: September 29, 2018, 12:25:42 PM »

The dongle (RTLSDR) is the weak link.  Overloads somewhat easily.  It works, but occasionally there is some intermod.  I have another, good quality A to D converter on the way to replace the existing dongle.

The RTLSDR was just to see if I could get everything working at all.

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KB2WIG
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« Reply #3 on: September 29, 2018, 02:03:40 PM »



  S,

I got a chance to listen in on the LoneLee Guys Net this AM.  Sounding good on my cellular telephone device. I think I'll try the record function and see how well I do.

klc
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steve_qix
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« Reply #4 on: September 30, 2018, 04:23:29 PM »

I did more work on the front end filtering, and the WebSDR is significantly improved at this point.

But will be putting in the new ADC when it arrives.

Seemed to have removed the CHU artifact that was in there, the so far, no overloads.  We'll see !


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Steve - K4HX
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« Reply #5 on: September 30, 2018, 09:38:04 PM »

The ADC is the weak link. Not enough bits.
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AJ1G
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« Reply #6 on: October 01, 2018, 01:24:18 AM »

Steve thanks for putting up the QIX WebSDR!  Nice to have one in the neighborhood so to speak, sometimes the K3FEF WebSDR is a bit too far away for copying New England stations.  Like how it defaults up to 3.885  MHz!

Only nit so far is that on my iPhone using Safari browser, the audio drops when I click to view the chat log

I've been running  a NooElec 25 MHz and up entry level RTL SDR dongle with their HamItUp 300 Hz to 25 MHz upconverter, they were Fathers Day and BDay gifts from son Dave.  Seem to work pretty well WRT to sensitivity and audio quality but yes there are significant intermod and aliasing images showing up. Biggest problem is the local AM station WBLQ on 1230 kHz 1KW about a mile and a half away.  Seems to be de-sensing things especially below the BC band.  Have yet to see any VLF signals, not even NAA on 24 kHz, that station always hammers in with a huge SNR on my Wandel & Golterman 4 khz to 18 MHz selective level meter, sometimes audible even with no antenna connected to the W&G. No pre-selection or input filtering on the SDR setup as of yet, just running my 80/75/40 meter inverted vee directly in to it so far. Using Cubic SDR software on an iMac in the shack.
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Chris, AJ1G
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« Reply #7 on: October 01, 2018, 12:11:27 PM »

Seems pretty good!

Trying it for the first time.
I've got an RTL.SDR dongle here too. Cheesy

Think I'll be needing a filter to drop out the BC band though...

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AJ1G
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« Reply #8 on: October 02, 2018, 04:50:04 PM »

Listening in the Tacoma right now to QIX mobile remote and the rest of the gang.  Great low end Steve...wicked good road rumble!  Your watthour meter at home must  be revving up every time  you key the mike. Looks very impressive on the spectral display!
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Chris, AJ1G
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« Reply #9 on: October 04, 2018, 12:39:17 PM »

Those little RTLSDR dongles have their downsides, but can't be beat for what they cost. Some guys use downconverters to make them play on HF better then they do using the direct sampling Q-channel method, but it does work. It works great for me as a 6 meter receiver for use with my Johnson 6 and 2 transmitter adapter. I was using a 6M rx adapter to other old receivers, but I like the SDR better. There is a fair amount of AM activity on 6 in New England and it would be great to have an online 6M omni SDR that is pretty much central like your location Steve. Whatsay you?
Larry
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« Reply #10 on: October 05, 2018, 12:26:00 AM »

The rtl devices are amazing....  For the price.  I'd brought them up years ago, and others have reignited them as well.  A gentleman from Italy, iirc, also posted a modulation monitor plug in you can use with one and sdr#.  Not a bad mod monitor, does every signal, including yours, displays POS and neg peaks, and costs what, ten bucks?

That said.  You REALLY need bandpass filters in front of them.  Like, they aren't an option, they need one.

Not only that, they are a gateway.  I still hold true, had I not discovered the rtl devi es five / six years ago, I'd still not have any sdr equipment at all!  Yes, rtl devices are a gateway drug!

And, as someone else said.  8 bits really isnt enough.  As soon as you experience a 12 bit sdr, its like, WHOA!


--Shane
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« Reply #11 on: October 05, 2018, 11:37:57 AM »

I've been impressed by them. I have a Stratux GPS and ADS-B in receiver package which apparently has a pair of them in there receiving on 1070 and 930 mhz. Seems to work pretty well, I see all kinds of stuff way up there in the sky while I'm puttering around in the Champ.

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73 de Kevin, WB2EMS
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« Reply #12 on: October 05, 2018, 03:58:54 PM »

This is great Steve! I noticed that the squelch is not working? What purpose is the auto notch thingy for?  Anyone?

 
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« Reply #13 on: October 05, 2018, 04:15:15 PM »

There is also a group of people on FaceLook that are light years ahead of me in what they are doing. Some are chasing satellites and others are into those new multi linked municipalities trunk systems. It took me about three days to get the software going. I have three different receivers going now but because of a recent windows update, I lost all my memories. Apparently my antenna here in Menands is not good enough for HF? Can't hear anything below about 23 mhz? This model is supposed to have the HF built in?


They can be found at this link if you are a member if FaceLook?

https://www.facebook.com/groups/rtlsdrdongle/

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KD6VXI
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« Reply #14 on: October 06, 2018, 05:47:38 AM »

Autonotch is a carrier / qrm remover.

I haven't had a lot of luck using them, at least on the remote sdrs.  The ones local to my pc, Autonotch filters work fairly good.

--Shane
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WA1LGQ
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« Reply #15 on: November 02, 2018, 02:20:46 PM »

Hey Steve I finally tried your websdr. It works very well. Nice job! I run my sdr's remotely sometimes, setting up some server software  that sends out the I/Q data to the remote PC and doing the processing locally. It is nice but it requires a good fast connection. Those RTL's are said to go down to 500 kHz but they go down a little easily to work pretty good as a receiver IF processor at 455. The IF output from the R390A is a bit too much for it without an attenuator and there is some time lag, but it adds the great detection stuff to the receiver, especially synchronous. The R390A makes a good preselector/bandpass filter for them.
Larry
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« Reply #16 on: November 02, 2018, 10:32:52 PM »

This is great Steve! I noticed that the squelch is not working? What purpose is the auto notch thingy for?  Anyone?

 

Another way to manage (eliminate) a nearby carrier is to drag that sideband in so that the offending carrier is outside of that (upper or lower) passband. Since AM sideband are identical, you can even drag one of them all the way in toward the carrier without losing either fidelity or S/N ratio.
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