From 2d0cb62973cfc5385eb8ce1ddcb4112bb3afc0dc Mon Sep 17 00:00:00 2001 From: Samy Kamkar Date: Sun, 22 Jul 2018 18:00:16 -0700 Subject: [PATCH] Added troubleshooting section --- FAQ.md | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/FAQ.md b/FAQ.md index 528f415..2b95e79 100644 --- a/FAQ.md +++ b/FAQ.md @@ -211,4 +211,13 @@ What is the minimum signal power level that can be detected by HackRF? This isn't a question that can be answered for a general purpose SDR platform such as HackRF. Any answer would be very specific to a particular application. For example, an answerable question might be: What is the minimum power level in dBm of modulation M at frequency F that can be detected by HackRF One with software S under configuration C at a bit error rate of no more than E%? Changing any of those variables (M, F, S, C, or E) would change the answer to the question. Even a seemingly minor software update might result in a significantly different answer. To learn the exact answer for a specific application, you would have to measure it yourself. -HackRF's concrete specifications include operating frequency range, maximum sample rate, and dynamic range in bits. These specifications can be used to roughly determine the suitability of HackRF for a given application. Testing is required to finely measure performance in an application. Performance can typically be enhanced significantly by selecting an appropriate antenna, external amplifier, and/or external filter for the application. \ No newline at end of file +HackRF's concrete specifications include operating frequency range, maximum sample rate, and dynamic range in bits. These specifications can be used to roughly determine the suitability of HackRF for a given application. Testing is required to finely measure performance in an application. Performance can typically be enhanced significantly by selecting an appropriate antenna, external amplifier, and/or external filter for the application. + +## Troubleshooting + +### Q: +Why is a known signal at an incorrect frequency, while adjusting the center frequency offsets the incorrect frequency even further or less? + +### A: + +You are probably using firmware not associated with the CPLD bitstream (firmware). If using the latest git code, first [update the HackRF firmware](../../tree/master/firmware/README), then [install the `host` code](../../tree/master/host/README.md), then [install the CPLD bitstream](../../tree/master/firmware/cpld/README), followed by powering the HackRF down and back up. \ No newline at end of file