# USRP1 warning "requested RX frequency is outside of the system range, requested RX frequency is outs **URL:** \ **Category:** GNU Radio\ **Created:** [August 14, 2015, 12:23pm UTC](https://www.ruby-forum.com/t/usrp1-warning-requested-rx-frequency-is-outside-of-the-system-range-requested-rx-frequency-is-outs/243004 "2015-08-14T12:23:36Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Sadaf\_N](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/858c86/32.png) [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\ **Post date:** [August 14, 2015, 12:23pm UTC](https://www.ruby-forum.com/t/usrp1-warning-requested-rx-frequency-is-outside-of-the-system-range-requested-rx-frequency-is-outs/243004/1 "2015-08-14T12:23:36Z")
Dear, Sorry if I have too much question, I am getting started with GNU radio, and I did not find the answer for this on the Internet. I have USRP1 and inside it has 2 daughter boards: WBX and RFX400. I run the FM receiving grc file and got this UHD Warning: Tune Request: 102.500000 MHz The ification: Target Frequency: 102.500000 MHz Clipped Target Frequency: 380.000000 MHz The RF LO does not support the requested frequency: Requested LO Frequency: 380.000000 MHz RF LO Result: 400.000000 MHz Attempted to use the DSP to reach the requested frequency: Desired DSP Frequency: 20.000000 MHz DSP Result: 20.000000 MHz Successfully tuned to 380.000000 MHz I changed various frequency and figure out the range that has Successfully tuned is from 380Mhz to 520Mhz. I don’t know why this happen, the WBX suppose to have range from 50Mhz to 2200Mhz. Does it come from the wrong firmware ? And moreover, my USRP has 2 daughter board, so how can I choose exact daughter board to use ? In UHD USRP source of GNU radio. only have options for antenna port for example RX2 or TX/RX, right ? Best regards, Hoang ---
**Author:** ![trbhoang](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/48db29/32.png) [@trbhoang](https://www.ruby-forum.com/u/trbhoang)\ **Post date:** [August 14, 2015, 3:31pm UTC](https://www.ruby-forum.com/t/usrp1-warning-requested-rx-frequency-is-outside-of-the-system-range-requested-rx-frequency-is-outs/243004/2 "2015-08-14T15:31:43Z")
On 08/14/2015 06:21 AM, Hoang Nguyen T. wrote: > The ification: > > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) > The UHD source includes a “subdev specification”. If your WBX is in the first slot, you’d use: A:0 If your WBX is in the 2nd slot, you’d use: B:0 As the subdevice specification. You can use: uhd\_usrp\_probe --args “type=usrp1” To get a listing of the device configuration, including which slot your WBX and RFX2400 cards are in on the USRP1. ---
**Author:** ![trbhoang](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/48db29/32.png) [@trbhoang](https://www.ruby-forum.com/u/trbhoang)\ **Post date:** [August 14, 2015, 3:36pm UTC](https://www.ruby-forum.com/t/usrp1-warning-requested-rx-frequency-is-outside-of-the-system-range-requested-rx-frequency-is-outs/243004/3 "2015-08-14T15:36:59Z")
Hi Hoang, the 380MHz is the lower frequency you can get with a RFX400. That’s correct. You can chose your daughterboard by using the number of channels argument (if you want both), or the subdev spec [1], like: B:0 to select the WBX in your second slot. Best regards, Marcus [1][USRP Hardware Driver and USRP Manual: Configuring Devices and Streamers](http://files.ettus.com/manual/page_configuration.html#config_subdev) ---
**Author:** ![trbhoang](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/48db29/32.png) [@trbhoang](https://www.ruby-forum.com/u/trbhoang)\ **Post date:** [August 16, 2015, 1:19am UTC](https://www.ruby-forum.com/t/usrp1-warning-requested-rx-frequency-is-outside-of-the-system-range-requested-rx-frequency-is-outs/243004/4 "2015-08-16T01:19:26Z")
Thank you, Now it works with exact frequency . On Fri, Aug 14, 2015 at 9:35 AM, Marcus Müller [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)