On my sansa E260 v1 I have the FM radio does not tune on the right frequency.
Example: to tune a station on 99.1 Mhz, I have to tune it to 99.15. If I tune it to 99.1 lots of static is heard. The same happens on all stations and it does not happen on the original firmware (tunes ok with no offset but I cannot confirm the frequency).
On the FM debug screen the frequency displayed when tuned correctly is 99264 kHz. I do not have fine tuning option to be more precise so that is as good as it gets (see attached).
The frequency also has a drift with time. Watching the debug screen, when it drifts lower to 99150 kHz the static starts to show up.
The device has a exceptionally good real time clock. It stays on time for as long as I have it (years). I have a feeling the reference clock used to tune the FM chip is not the best of option.
The CPU frequency shows as 30000000 which I assume is 30MHz.
My questions for the hardware gurus:
Is the real time clock used at all as a reference in the tuning algorithm?
Can we fine tune ? The presets have a lot of zeros in the frequency, but the best I can do is using the Other region that allows for 50 KHz steps.
A non related question, just for my knowledge. The device has a dual CPU. Does rockbox take advantage of that?
Topic: Sansa E200 v1 FM tuning frequency is off (Read 1214 times)
