It could be acting like a short circuit, and you would see no difference switching the TX amp on or off. I'm sure it depends on the mode of failure.
IC's U13 & U25 are part number MGA-81563-TR1G one is for RX and the other is TX. I think U13 is RX and U25 is TX, you should to load up the schematic in KiCAD and check. (source: https://github.com/mossmann/hackrf/blob/master/doc/hardware/hackrf-one-bom.csv ) Probably best to verify with the hackrf_transfer command as well before masking the board with aluminium foil, kapton tape and blasting with hot air. On 31/01/2015 23:24, Mark Jessop wrote: > I was using GNURadio Companion, not hackrf_transfer for my tests. > I experimented with varying all of those parameters, and could not get an > output any higher than -30dBm. > > If the TX amplifier was broken, i would have expected to see a noticeable > difference when i switched the amp on and off (i.e. RX LNA gain between 0 > and 14dB), as from what I could tell in the schematic doing so would switch > the amp in and out. > > Cheers, > Mark > > On Sun, Feb 1, 2015 at 2:33 AM, Paul Connolly <[email protected]> wrote: > >> Are using -c 127 as an argument for your testing. And -x goes from 0 to >> 47dB, why stop at 14dB ? >> $ hackrf_transfer >> receive -r and receive_wav -w options are mutually exclusive >> Usage: >> ... snip ... >> [-l gain_db] # RX LNA (IF) gain, 0-40dB, 8dB steps >> [-g gain_db] # RX VGA (baseband) gain, 0-62dB, 2dB steps >> * [-x gain_db] # TX VGA (IF) gain, 0-47dB, 1dB steps* >> ... snip ... >> [-c amplitude] # CW signal source mode, amplitude 0-127 (DC value >> to DAC). >> ... snip ... >> $ >> >> From https://github.com/mossmann/hackrf/wiki/HackRF-One#transmit-power >> you should be seeing about 15dBm that close to 10MHz >> >> It could be that you have damaged the TX amplifier, did you have -a 0 in >> your tests. Because if it is broken then it would probably act like an >> attenuator. >> >> Paul >> >> >> On 31/01/2015 12:43, Mark Jessop wrote: >> >> Hi all, >> >> Bought a HackRF a few months back, never properly measured the output power >> on it when I got it unfortunately, but it has certainly dropped at some >> point in the last few months. >> >> I finally got the chance to put it on a spectrum analyzer the other day. >> Transmitting a single carrier, I'm seeing a maximum of -30dBm output power >> at 14MHz. Only a few dB difference noticed when turning the RF Gain setting >> from 0 to 14dBm (This does actually do something, doesn't it?) >> >> Any thoughts? I have the facilities to replace QFN components if required... >> >> Cheers, >> Mark VK5QI >> >> >> >> >> _______________________________________________ >> HackRF-dev mailing >> [email protected]https://pairlist9.pair.net/mailman/listinfo/hackrf-dev >> >> >> >> _______________________________________________ >> HackRF-dev mailing list >> [email protected] >> https://pairlist9.pair.net/mailman/listinfo/hackrf-dev >> >>
signature.asc
Description: OpenPGP digital signature
_______________________________________________ HackRF-dev mailing list [email protected] https://pairlist9.pair.net/mailman/listinfo/hackrf-dev
