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Andrey Sviyazov andreysviyaz at gmail.comHi Joel. > 2. What is the power output in dbm of your umtrx? >> > After fixing this issue<https://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified>I measured + 20 dBm for 900 MHz band and +17 dBm for 1800. > > I will be testing this UMTRX with a DCS amp with 10 dBM input. Just to be > sure, I just need to adjust attenuation to at least 7 dBM and 8 probably to > avoid clipping the RF amp as below: > > GSM.Radio.PowerManager.MaxAttenDB 8 > GSM.Radio.PowerManager.MinAttenDB 0 > Please explain more what att do you try to use and what clipping do you mean (may be 1dB gain compression) ? Anyhow, you can easy adjust output signal of UmTRX by using --gain in case of UHD TX control. Also can be used TXVGA2 gain in case of direct LMS registers control via Python scripts. > Is using an LNA with BPF advisable with your UMTRX? > Yes of course. External LNA and duplexer or band pass filter should be used for better NF performance. > > What is the operating temperature of your UMTRX as I want to make sure the > HD case I am using for testing is good enough. I installed a small fan and > so far temperature is around 40 deg C. > You can find on the board FUN2 control IC (U35) MAX6665ASA45<http://datasheets.maximintegrated.com/en/ds/MAX6665.pdf> . So, at the PCB temperature +45'C FUN2 must start to cooling. And if you do not use FAN2 (or broken) then this IC will switch off UmTRX at temperature 45+30=75'C. Low temperature limit is minus 40'C due to industrial components (is not tested 100% in production). > The LEDs are on the board and I may want to solder some LEDs to monitor > status, where on the board can I terminate the power for LEDs? > You can use any DC-DC output higher 2V through current limiting resistor. Pleas refer to datasheet of your LED's type to find proper resistor value. > > On Tue, Mar 5, 2013 at 10:16 AM, Andrey Sviyazov <andreysviyaz at gmail.com>wrote: > >> Hi Joel. >> >> On Fri, Feb 22, 2013 at 6:28 PM, joel yabut <joel at jointventure.com> >> wrote: >> >>> > May i know the following specs >>> > 1. What is the tx and rx isolation of umtrx? >>> >> Not yet measured and unfortunately there are no info from Lime Micro. >> >> > 2. What is the power output in dbm of your umtrx? >>> >> After fixing this issue<https://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified>I measured + 20 dBm for 900 MHz band and +17 dBm for 1800. >> >> >>> >>> > 3. How is the lna on the rx input and is an external lna and bpf >>> > recommended? >>> >>> For Fairwaves 10W base stations we're developing UmSEL, which has >>> channel filter and an additional LNA. For the use without amplifier >>> you don't need any additional filters or LNAs. >>> >>> > 4. What is the main advantage of umtrx compared to usrp by ettus? >>> >>> If you want to use it for GSM, then it's cheaper and gives you >>> dual-channel support. >>> >>> -- >>> Regards, >>> Alexander Chemeris. >>> CEO, Fairwaves LLC / ООО УмРадио >>> http://fairwaves.ru >>> >>> Best regards, >> Andrey Sviyazov. >> > > > > -- > Mother Ignacia Avenue corner Scout Rallos St. > Quezon City, Metro Manila, Philippines > > Best regards, Andrey Sviyazov. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.osmocom.org/pipermail/umtrx/attachments/20130310/d2773d39/attachment.htm>