If you look at the bottom right hand corner of the third page (the HackRF One front end) of https://github.com/mossmann/hackrf/blob/master/doc/hardware/hackrf-one-schematic.pdf
The SMA antenna (P4) is followed by a transient-voltage-suppression diode to protect the circuit (ESD), which is followed by the Bias-T blocking capacitor (C64), then it enters a single-pole triple-throw switch (U14 - SKY13317), there are three possibilities: The TX amp (U25) is connected to the Antenna. The bypass path is connected to the Antenna. The RX amp (U13) connected to the Antenna. The symptom of a blown amp is that when it is switch into the signal path it acts like an attenuator (lower SNR) instead of a providing gain, relative to it being bypassed. So you will see a higher SNR with the amp bypassed. On 01/07/2015 16:02, Daniel Bernhardt wrote: >> Now the amp is presumed blown it acts more like an attenuator, i.e. signals >> are weaker with it switched on. > Not regarding your specific case: > Is there a definitive way to determine if ones preamp is blown or not? For > all we know it could be a faulty antenna setup or a cabling issue. Is the amp > completely bypassed if turned off or just not amplifying? What are the > symptomps of a "blown" amp? Does it short or are there signals coming through > much weaker due to some cuppling effects? > Forgive my ignorance on the matter. Just beeing curious. > > Daniel > _______________________________________________ > 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
