Is it possible that you have the cables on the wrong port? Sent from my iPhone
> On Nov 9, 2020, at 1:16 PM, Moses Browne Mwakyanjala <mbkit...@gmail.com> > wrote: > > > Hi, > The flowgraph contains a sinusoidal source and a USRP sink. You may notice > that the sample rate is quite high. It is part of the requirements. > Regards, > Moses. > <image.png> > > >> On Mon, Nov 9, 2020 at 6:19 PM <discuss-gnuradio-requ...@gnu.org> wrote: >> Send Discuss-gnuradio mailing list submissions to >> discuss-gnuradio@gnu.org >> >> To subscribe or unsubscribe via the World Wide Web, visit >> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> or, via email, send a message with subject or body 'help' to >> discuss-gnuradio-requ...@gnu.org >> >> You can reach the person managing the list at >> discuss-gnuradio-ow...@gnu.org >> >> When replying, please edit your Subject line so it is more specific >> than "Re: Contents of Discuss-gnuradio digest..." >> >> >> Today's Topics: >> >> 1. Re: Measuring transmission power from USRP B210 (Marcus D. Leech) >> >> >> ---------------------------------------------------------------------- >> >> Message: 1 >> Date: Mon, 09 Nov 2020 12:01:24 -0500 >> From: "Marcus D. Leech" <patchvonbr...@gmail.com> >> To: discuss-gnuradio@gnu.org >> Subject: Re: Measuring transmission power from USRP B210 >> Message-ID: <5fa975e4.9020...@gmail.com> >> Content-Type: text/plain; charset="utf-8"; Format="flowed" >> >> On 11/09/2020 11:39 AM, Moses Browne Mwakyanjala wrote: >> > Hello everyone, >> > I'm in the process of testing a GNU Radio transmitter. The transmitter >> > will be connected to a solid-state power amplifier (SSPA) for >> > near-Earth satellite communications. The SSPA expects an input of 0dm >> > from the USRP TX port. >> > >> > The first step is thus to measure the power from the USRP. To that >> > end, the flowgraph generates a complex sinusoidal signal with a unit >> > magnitude. The UHD:USRP Sink block is set to maximum gain (i.e. >> > normalized gain of 1.0). Unfortunately, the maximum power I can see >> > from the spectrum analyzer is around -6.93 dBm as shown below. To my >> > understanding, the USRP can transmit up to 20 dBm as reported in the >> > "External Connections" section at this Ettus link : >> > https://files.ettus.com/manual/page_usrp_b200.html. >> > Could anyone explain why I can't achieve a 20 dBm (or anything around >> > it) power level? >> > IMG_3475.JPG >> > Thanks in advance, >> > Moses. >> > >> Could we perhaps see a minimal flow-graph that demonstrates the issue? >> >> Generally, setting the baseband magnitude to 1.0 at the same times as >> setting to MAX gain can cause linearity issues. >> >> >> -------------- next part -------------- >> An HTML attachment was scrubbed... >> URL: >> <https://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20201109/e3b13728/attachment.html> >> -------------- next part -------------- >> A non-text attachment was scrubbed... >> Name: not available >> Type: image/jpeg >> Size: 1112823 bytes >> Desc: not available >> URL: >> <https://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20201109/e3b13728/attachment.jpe> >> >> ------------------------------ >> >> Subject: Digest Footer >> >> _______________________________________________ >> Discuss-gnuradio mailing list >> Discuss-gnuradio@gnu.org >> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> >> ------------------------------ >> >> End of Discuss-gnuradio Digest, Vol 217, Issue 10 >> *************************************************
