How about sdr for android cell phone?

[humblegeo]

Anyone fooled with this? I have a Samsung android cell phone S7 but also have an older Samsung Galazy S3 available, with the micro usb to female usb adapter and a DVB-T+DAB+FM RTL-SDR device. I have downloaded from the play store to the cell phone the SDR Touch app. That's as far as I have gotten. What's next?

Appreciate the help
Larry G

 

[scruggsy]

watching!

 

[Markb]

Have you downloaded the driver and are you using a USB OTG cable and not a simple adapter?

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[br0adband]

Plug in the OTG cable (do that with the USB stick already attached to the cable - it's weird, yes, but I've found over the years that attaching a USB device to the OTG cable before then attaching the cable to the smartphone or tablet works better initializing the USB device (whatever it is).

Once everything is attached, and as long as you've installed the SDR Touch app + the RTL-USB driver required (the first time you run the SDR Touch app it will tell you if the driver isn't installed and if it's not then it'll link you to the Play Store to get it installed, it's free).

USB stick attached to OTG cable - check
OTG cable attached to smartphone/tablet (with OTG support and the S3 and the S7 both have that) - check
SDR Touch app + RTL-USB driver installed on device - check

Run the SDR Touch app and explore the functionality. If you're using the trial version of the app it will function indefinitely for tuning/listening purposes but the spectrum display functionality will only work for 1 minute at a time. It's still fairly limited in scope but it does work and works quite well for what it offers and since there's really no other competing app(s) out there it's basically the only option. I had hoped the author would add a lot more functionality to the app, potentially even some digital decode capability either directly or with plugins but that hasn't happened and may never come to fruition.

I've always had an issue with the cost of the SDR Touch app because it hadn't been updated in a long long long time but apparently a few of us emailing the author earlier this year did prompt him to finally push an update in August 2017. The author of the app works for some company now that has some restrictions on his outside programming. I don't know all the details, I just read someplace in late 2016 that the author was under contract for some job - I think he works for Amazon actually - that put restrictions on what he was able to do in his own free time (kinda crappy to be put under such limits) in terms of coding for profit, I have no idea really.

Anyway, I may have to check out the latest build and see how it performs. I've been using Google Rewards for the past few years (answer survey questions and earn a small amount of Google Play Store credit for my time) and I have more than enough stashed at the moment to get the full app for $9.99, might have to do it once and for all since it wouldn't be costing me anything out of pocket at this point. My current smartphone unfortunately doesn't support OTG, however, so that's kinda crap.

 

[Flatliner]

One thing about modern kit that really gets my goat, is the lack of a dedicated power port. Anyone who has tried to get a phone with a dongle attached AND a battery pack to work together, will understand. These SDRs soon put paid to a phone's battery life, though I suppose the whole assembly does make a very good hand warmer, and winter is only just around the corner.

 

[humblegeo]

Well thanks for all the help but it didn't work out for me so far. I downloaded from play store SDR Touch app and the RTL-SDR Driver. I don't have a cable to interface dongle to cell phone, all I have is the Samsung usb adapter which plugs into the cell phone and then dongle plugs into the adapter. The one youtube video I did watch showed using this same small white Samsung usb adapter and that particular setup seemed to be working fine on the youtube video. The driver said it installed correctly and said please launch your host application and it will trigger the driver automatically, which I did and got the following message: No compatible device found. make sure your usb device is connected properly and your phone/tablet supports usb host mode. I also noticed that the light on the dongle was not on.

Might be my issue is has to do with USB Host Mode not configured on my phone??

I also ran across this comment on the internet "I received a new Samsung Galaxy S7 yesterday when upgrading my phone. It comes with a USB-2-Go adapter to use for data transfer. I was curious to see if it would work with an RTL-SDR dongle and, sure enough, it works!
I downloaded the RTL2832U driver app and the SDR Touch demo app. I've also got an ADSB app as well. Now, I can sit at work during lunch and monitor air traffic."

 

[Markb]

It is not going to work if you do not have a USB OTG cable. A simple adapter is not going to do the trick.

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[humblegeo]

I think your probably right, something about the way the USB OTG cable is wired activates USB Host Mode. Can I just buy one from Ebay or maybe locally?

 

[Markb]

Yes, I think your best bet is either eBay or Amazon.

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[humblegeo]

Ok, I'll get a Samsung compatible USB OTG cable and go from there. Thanks for the help.

Larry G

 

[bharvey2]

Anyone fooled with this? I have a Samsung android cell phone S7 but also have an older Samsung Galazy S3 available, with the micro usb to female usb adapter and a DVB-T+DAB+FM RTL-SDR device. I have downloaded from the play store to the cell phone the SDR Touch app. That's as far as I have gotten. What's next?

Appreciate the help
Larry G

While I haven't set up a dongle on a cell phone, I've done it on a number of Android tablets. Follow br0adband's instructions and you'll be off and running. I used the paid version of the SDR software. It works like a charm.

 

[HM1529]

I didn't have much success using an SDR app just yet. But, last night, I got my OTG cable in the mail and was able to get the dongle working with some ADS-B apps. Running the dongle does burn through phone battery pretty quickly, though...at least on my LG G3. I'll keep playing with the SDR stuff to see if I can getting it working.

 

[rbm]

This what I've done in the past.

Rich

Android phone, OTG cable, and RTL2832u driver

 

[K5MPH]

It is not going to work if you do not have a USB OTG cable. A simple adapter is not going to do the trick.

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Your right it works fine for me on my LG,I just had to get a USB OTG cable and it works fine.....

 

[Markb]

Something like this:


https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/302501606793


I haven't tried it, but it might be worth looking into.

OTG with power..........



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[humblegeo]

Just purchased it. $3.99 with free shipping. So this will require external power for the dongle but will prevent dongle from draining cell phone battery? I think I will also get the standard USB OTG cable as another option to use if I am out and about.

Thanks again

 

[bharvey2]

I didn't have much success using an SDR app just yet. But, last night, I got my OTG cable in the mail and was able to get the dongle working with some ADS-B apps. Running the dongle does burn through phone battery pretty quickly, though...at least on my LG G3. I'll keep playing with the SDR stuff to see if I can getting it working.

Oh yeah, drains the battery like crazy. I bought a few OTG cables that have an additional female USB end (Like the one MarkB linked to). The cable allows me to plug in the SDR dongle and plug in another USB cable that I connect to a USB power supply. That minimizes the problem but naturally ties you to a power source.

 

[Flatliner]

I've seen a few sellers claim that their cables can charge the phone at the same time as allow the OTG to work. I've never found one that actually does that at all. It's likely a function of OTG, than of the cable.

 

[br0adband]

As noted above by Flatliner, pretty much every single OTG cable out there that claims to support charging never actually does - that eBay component in the post above by Markb clearly states in the text of the ad:

**Note: This is not designed to charge the phone or tablet. The power source provides power to the external source such as a mouse or external hard drive.

And yes it has to do with how OTG works as I understand it: USB hardware can only effectively "lock on" to one device at a time for one purpose so the charging aspect using the microUSB cable requires some detection work to say "Oh, there's a charger attached..." but that doesn't happen with an OTG cable which is wired a bit differently to give the device/usage priority to the USB device attached to it. Using such a cable will allow the USB device on the OTG cable to be powered directly and it should not drain the smartphone/tablet battery because of it being in use, the only way to know for sure is get that modded power for OTG cable and see what happens.

The only really effective way to do this - use a smartphone + an OTG cable + an RTL-SDR device (or something else like an SDRplay or Airspy if there's driver support, actually) - would be to have a smartphone attached to an external battery case like something from ZeroLemon or some other maker which supports an external charging port on the external battery case itself. That way, when everything is working strictly on the external battery, you could then plug in a microUSB charger to the external battery and it would charge it and power the device simultaneously and the OTG aspects would never have any problems since it's not involved in this at all.

Earlier this year I had a Samsung Galaxy Note 4 along with a ZeroLemon 10,000 mAh external battery case and was able to do exactly what I just described. No, it's not very convenient to do it in terms of the hardware you'd carry around but at one point I was going to do some case hacking (the external battery casing) and gut out a portion of it to place the RTL-SDR board (after being removed from the plastic case it came in) inside the battery casing. I had it all worked out and was even going to be able to mount a telescopic whip antenna or an SMA antenna connector on the external battery case and literally make it truly portable, in a self-contained smartSDR (that's what I was going to call it basically).

Never got around to finishing it because it was nearly impossible to find a decent microUSB cable short enough and with the proper type of 90 degree right-angle connector my layout required, maybe someday if I find another Galaxy Note 4 for cheap I might try that again, who knows.

 

[nowires]

Try SDRoid from Play Store.
Also have tried using a powered USB hub (that you'd use on a computer), and it doesn't charge AND use the usb device plugged into the hub in *ANY* possible configuration that I've tried so far.