USB Dongle numbers and FMP24

Status
Not open for further replies.

W4KRR

Member
Premium Subscriber
Joined
Apr 1, 2001
Messages
3,434
Location
Coconut Creek
When using USB dongles with FMP24, it sometimes refers to dongle 1, dongle 2, etc. ("Found Rafael Micro R820T Tuner") I have several USB dongles plugged into a USP strip, how do I know which one is #1, #2, etc? What I currently have to do is to disconnect all dongles except for the one I want to use, if I want to use a specific one. If I specify a dongle number in a batch file, it tells me it can't find #1, #2, or whatever.
 

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
One can change dongles serial number by using the program "rtl_eeprom.exe". My ones all shared the same serial number. but by changing them, one can identify the individual dongles.

"rtl_eeprom.exe" comes with SDR#, I think...


Type in "rtl_eeprom.exe -h" for a list of commands using command prompt (cmd.exe).
 

slicerwizard

Member
Joined
Sep 19, 2002
Messages
7,643
Location
Toronto, Ontario
When using USB dongles with FMP24, it sometimes refers to dongle 1, dongle 2, etc. ("Found Rafael Micro R820T Tuner") I have several USB dongles plugged into a USP strip, how do I know which one is #1, #2, etc?
Run FMP24 -i1 and see which dongle's antenna you have to remove to affect the spectrum display. Repeat for -i2, etc.

One can change dongles serial number by using the program "rtl_eeprom.exe". My ones all shared the same serial number. but by changing them, one can identify the individual dongles.
Doesn't help when FMP24 doesn't display serial numbers:

SDR device count=1
Found Rafael Micro R820T tuner
Found Rafael Micro R820T tuner
Tuner type=5 (R820T)
Sampling rate set to 2.400000 MHz
...
 

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
"Doesn't help when FMP24 doesn't display serial numbers:"

Oh good point! I am trying to remember WHY I set separate serial numbers now.



Well I run 2 v3 dongles with frequency correction of '0' due to the crystal ovens. I feed 1 aerial (wide band discone) into a 2 way TV splitter (with F connectors) and then to each dongle. This way I don't need to worry about which one is which. This may not work with your config, but works great for me.

Sorry about any confusion.
 

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
I think WHY I set individual serial numbers was because dongle '0' and '1' (with same serial number) would sometimes swap over, presumably due to initialising and being detecyted at different times? This affected my other older setup as f corrections were approx +62 and +32. This caused issues! I had to swap USB ports over by unplugging dongles and switching them.
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
7,425
Location
Suffolk County NY
I am trying to remember WHY I set separate serial numbers now.


Unitrunker 2.0 maybe?

I am running 2 nooelec dongles at the same time. 1 shows as the generic serial number (00000001) and the other shows something different.
RTL2838UHIDIR:00000001
RTL2838UHIDIR:8&2033C819&0&4

Since they are good dongles, and don't seem to need a ppm correction, I have no issues at all.

When I run sdr#, I just select rtl usb, and it fires up regardless of what's connected. I have nooelec hooked up all the time.

Same thing when running 2 instances of fmp24. No issues at all


ut2.JPG
 

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
"Unitrunker 2.0 maybe? "

May be Dave (my poor brain). I have 2 dongles, one made in 2016 and the other 2017. I use the date of manufacture as the serial (6 digits, 021116 or 120317 for eg.). Helps to disambiguate them. I do use UT...
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
7,425
Location
Suffolk County NY
I have not had to change any serial numbers with the nooelec dongles at all. I did have a problem with the cheap sh*t china dongles a while back. I only changed one of them. Can't remember the application that was giving me trouble.

Nooelec dongles rock!
 

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
Mine are the v3 ones, which work great for the price. Initially I used the v1 ones with the bad offsets.


Ah, CCC. "Cheap Chinese Cr@p" ! Don't start me...
 

M105

Member
Joined
Sep 13, 2005
Messages
399
I have 4 old dongles each with correction factors. The good news is that once they come up on Windows7 they do return to the same numbers on subsequent reboots. The bad news is, if you change things in the USB setup then it is a crap shoot and you have to figure out which dongle is which all over again. I have tried to rename and reorder them in device manager until I went further insane but never found a method to make Windows 7 always put them in the same order. This is a PITA but looks to be an inherent problem. I also see similar issues with sound devices that change numbers when the system is disturbed.

If anyone has solutions, I would love to hear how it is done!
 

GTR8000

NY/NJ Database Guy
Database Admin
Joined
Oct 4, 2007
Messages
15,412
Location
BEE00
I have several dongles of various origin. A few of the original cheap non-TCXO from China (63 and 180 ppm drift, yikes), two of the v1 RTL-SDR.com 1.5 ppm TCXO, and two of the NooElec NESDR SMArt 0.5 ppm TCXO.

Instead of screwing around with them all having the same default 00000001 serial #, I've modified them all using rtl_eeprom. The NooElec are now 00000010 and 00000011, the RTL-SDR.com are 00000020 and 00000021, and the cheap ones reflect the ppm, 00000063 and 00000180.

I also disabled the IR receiver with rtl_eeprom, which pretty much guarantees that they won't show up as multiple BULK IN INTERFACE entries, instead showing up as a single RTL2838UHIDIR entry each.

Long story short, if you keep all of the serial #'s 8 digits long and put them in some sort of sequence, I've found that they will usually line up with Device 0, Device 1, etc. So in my case, Device 0 = 00000010, Device 1 = 000000011, Device 2 = 00000020, and so on.
 

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
"but never found a method to make Windows 7 always put them in the same order. "

Same with USB serial port adaptors! Threw mine in the bin. Luckily my old quad core is fairly fast (even 8 years later!) and has a real serial port. But I digress.


ps. $60 for a pair of v3 silver dongles ain't too bad. Has saved me a lot of frustration time as one is 0 and the other is only about +0.5 offset.


"I also disabled the IR receiver with rtl_eeprom, which pretty much guarantees that they won't show up as multiple BULK IN INTERFACE entries, instead showing up as a single RTL2838UHIDIR entry each."

Interesting! I did not know that Beavis (I am Cornholeio!), um, I mean GTR8000 ! I am off to have a play with that. I will report results.


I also read that one master clock oscillator on a dongle can be fed to another. May be even more than one more, depending on it's current drive capability, I guess. A transistor buffer could be made up, I guess. So one ovenised osc can be made to feed our old non ovenised dongles.
 
Last edited:

TheButcher

Member
Joined
Jun 12, 2013
Messages
269
So yea... Run cmd to launch command prompt. If necessary, change directory to rtl_eeprom.exe, or copy the file into PATH.

rtl_eeprom -h (Shows help)
rtl_eeprom -i0 (Invokes first dongle, device 0 to disable IR port. Get asked y or n)


Soo from that...
rtl_eeprom -d0 -i0 (Select y, IR port device 0 disabled.)
rtl_eeprom -d1 -i0 (Select y, IR port device 0 disabled.)

If you have a third dongle, use -d2

That worked and dongles still worked afterwards. I hope that helps... :love:



Same process for serial number change...

ps. I had to manually unplug and plug back in the 2 dongles and guess what? It worked!

pps. And ensure you use Zadig version 2.4 (as a reminder, -latest version at this point).

ppps. IR port is used for the remote control. On my older v1 dongles, I actually removed the IR sensor to save a little power as it was not needed. Either unsolder or just chop it off with side-cutters.


Tip: With the old plastic dongles I removed and threw out the plastic covers and soldered on a length of stranded wire to an earth point. I then wrapped the dongle up in insulation tape, taking care to leave the wire exposed by say, 2cm or 1". Then wrap the dongle in alluminium foil. Fold and spread out the stranded wire onto the foil. Then tape up in another layer of tape. Presto! 100% shielded dongle.
 
Last edited:
Status
Not open for further replies.
Top