xv6700 Screen Noise - High Pitched Buz

[dbrahms]

so, I've seen several forum comments on other sites (none as good as this of course) that mentioned the high pitched screen noise that starts to spew out of this device after a week or so. None are too recent and wanted to see if anyone found a fix that I have not seen ? Anyone really nail down what the problem is anyway ?

If you are uinfamiliar with this issue, hold your xv6700 (or xv6600) up to your ear. Not the earpiece but the screen itself. Hear a high pitched noise similar to a tube TV's high pitched noise when you first turn it on ?

[lesterm]

A lot of Palms used to do it - our old Zire71 done it and this was common. I think some people cured it by over/under clocking very slightly.

Hope this is of some help

[dbrahms]

already tried to overclock utilities..going from 200mhz to 600mhz and still the same problem. thanks for the reply though.

[lukas44a]

also see if makes a difference when you turn light on/off..
I used 2 see that in and old pda of mine :roll:

[John Schaefer]

Hear a high pitched noise similar to a tube TV's high pitched noise when you first turn it on ?

Nope, and I have good HF hearing. My unit does not have that behavior.

My engineering guess would be that you have faulty hardware. I don't know the circuits used, but perhaps there's a switching supply/convertor to drive the screen backlight. If so, there could be an issue with magnetostriction creating a degree of microvibration at the fundamental or a harmonic of the switching frequency, combined with an accidentally critical clearance of the magnetostrictively affected component to something else that's rigid and acoustically radiative at the frequency in question. The magnetostrictive component vibrates, at one excursion limit it smacks into the acoustically radiative component, significant sound amplification results.

Or, instead of magnetostriction, it could be an inductor developing a drive-frequency force against its core or a nearby ferrous element.

Anyway, faulty hardware of one kind or another.

[jamesmct]

Its funny, because I used to have the same problem with my Treo 650 when it first came out. It is actually the antenna wire that goes behind the screen. The high pitch sound is coming from the frequency passing through the wire and being picked up by the screen when its turned on. They came out with a fix for the original 650's and I think Palm actually released a second generation 650. As for the UTC er... PPC... er... XV6700, all these stupid names... I would bring it back to Verizon because that is definetly a hardware defect that shouldn't be happening. Just out of curiousity, which version do you have... the one with the white letters on the keyboard, or the blue letters. You might have the older generation 6700.

[bigray327]

My brand new XV6700 does it. I'm thinking about taking it back.