PSOne Screen speaker/amp problem SOLVED!

Website · Post by **Life of Brian** » Sat Aug 12, 2006 5:46 pm

Excellent! I actually have some free LM386 samples coming my way - good thing I ordered more than one! I think having a volume knob would be badass for my SNESp, and I don't mind having to do this at all. It's an excellent excuse to learn about audio amps, of which I have already learned a lot over the past day or two.

Thank you very much, segasonicfan. You've pointed me in the right direction and I think I can carry on from here.

...good thing I haven't cut holes for the volume/brightness adjusts yet

lifeisbetterwithketchup · Mon Aug 14, 2006 12:04 pm

If the main problem is the level of audio is too high, why can't one just put a resistor on the input audio line? I know this sounds too simple, but why not?

Edited for clarity.

segasonicfan · Post by **segasonicfan** » Mon Aug 14, 2006 5:30 pm

No, that is not the problem. The problem is voltage spikes in the grounding to the audio circuit. The analogue and digital voltage inputs were not properly seperated on the board and so all the interference with the amp is duplicated through the screen output. That's why completely ungrounding the chip and applying grounding only to the voltage input is the solution (other than putting in a new amp).

Glad to hear everything it working out for ya joedog ;)

-Segasonicfan

jmetal88 · Post by **jmetal88** » Thu Dec 28, 2006 1:07 pm

I've been reading over this topic hoping to find some answers, but I have found absolutely nothing which helps me. Can someone please point out where the audio amp is and which traces I would go about isolating? Or at least tell me which chip or circuit the audio amp is so I can figure out how to isolate it myself. This problem is very severe in the portable Jaguar I am trying to make. It affects the screen at any more than 1/3 volume.

Website · Post by **Life of Brian** » Fri Dec 29, 2006 11:20 am

Well, my first question to you is what batteries are you using? Also, are you using a PSOne screen or something else?

jmetal88 · Post by **jmetal88** » Fri Dec 29, 2006 11:56 am

joedog86 wrote:Well, my first question to you is what batteries are you using? Also, are you using a PSOne screen or something else?

Hi Joe, thanks for responding!

Actually, I am not using batteries yet, I am powering the whole assembly from the Jaguar's AC adapter. The LCD is getting power from the Jaguar's power switch through a 10-ohm resistor (for some reason powering it directly produced large grey bars on the screen, but through the resistor the picture is fine until the speakers are plugged in). I eventually intend to power it from a battery of rechargeable C-cells, however. And yes, I am using the PSOne screen. I don't believe I would have posted in this specific topic if I hadn't been.