Search found 1677 matches

by exxos
Tue Apr 24, 2018 9:38 pm
Forum: TWEAKS & FIXES
Topic: Hissing and whistling in the STe audio output
Replies: 38
Views: 1051

Re: Hissing and whistling in the STe audio output

I have heard noise on my STE's, but I only used headphones direct. Pressing spacebar pretty much deafened me it was that loud. so any noise I should hear it easily. I did hear a tiny bit, more so on RAM access, but my dac fix solved it, but I could barely hear it to start with.
by exxos
Tue Apr 24, 2018 9:30 pm
Forum: TWEAKS & FIXES
Topic: Hissing and whistling in the STe audio output
Replies: 38
Views: 1051

Re: Hissing and whistling in the STe audio output

OK finally got it recorded..

This is pure PC noise... after 10 seconds I start graphics tests...


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by exxos
Tue Apr 24, 2018 9:04 pm
Forum: TWEAKS & FIXES
Topic: Hissing and whistling in the STe audio output
Replies: 38
Views: 1051

Re: Hissing and whistling in the STe audio output

OK, I hooked up my STE to my PC.. I hear the sounds I think.. but this is PC noise... Can't seem to record it in audacity... but when I run graphics test, sound goes mental.. I always disable the line input jacks on my sound card because I always hear loads of noises... makes no odds if the STE is p...
by exxos
Tue Apr 24, 2018 8:43 pm
Forum: TWEAKS & FIXES
Topic: Hissing and whistling in the STe audio output
Replies: 38
Views: 1051

Re: Hissing and whistling in the STe audio output

Paulo P wrote:
Tue Apr 24, 2018 8:27 pm
I understand. So, if you would have time sometime, please record your machine(s) to find out if all machines are the same and the hissing appears there too.
I will try and do that later this week...
by exxos
Tue Apr 24, 2018 8:13 pm
Forum: TWEAKS & FIXES
Topic: Hissing and whistling in the STe audio output
Replies: 38
Views: 1051

Re: Hissing and whistling in the STe audio output

No, I didn't run memory test software yet... but I have this feeling that the more RAM access, the worse noise is in the audio out. No matter if it is a direct stereo output or monitor audio (pin 1). So, the question is why and if there is a possibility to defuse this noise and interferences. And w...
by exxos
Tue Apr 24, 2018 7:52 pm
Forum: TWEAKS & FIXES
Topic: Hissing and whistling in the STe audio output
Replies: 38
Views: 1051

Re: Hissing and whistling in the STe audio output

Have you run memory test software and checked the audio noise ? Can't remember if its been talked about before, though I think some noise is RAM access noise. So more RAM access, the worse the noise should get..
by exxos
Tue Apr 24, 2018 7:49 pm
Forum: PSU (power supplies)
Topic: TT/Mega STE power supply headaches
Replies: 42
Views: 384

Re: TT/Mega STE power supply headaches

The meter seems to be ok - it doesn't show any voltage (maybe a few mV) a few mm from that spot...). I thought it might be some sort of transparent residue that is conducting but I cleaned the pad area and checked multiple times - nothing. The track is maybe 1cm at most and again - nothing that cou...
by exxos
Tue Apr 24, 2018 7:19 pm
Forum: PSU (power supplies)
Topic: TT/Mega STE power supply headaches
Replies: 42
Views: 384

Re: TT/Mega STE power supply headaches

when the base is not connected to the pcb it reads 0v (around 100mV, hard to say exactly) and there/s 0.6v on the pad (Zener diode is desoldered so the pad just a piece of copper on the pcb disconnected from anything). Forgive me if this sounds dumb.. but have you tried moving your scope probes and...
by exxos
Tue Apr 24, 2018 7:02 pm
Forum: PSU (power supplies)
Topic: TT/Mega STE power supply headaches
Replies: 42
Views: 384

Re: TT/Mega STE power supply headaches

BTW - I updated my previous post (re: 5v shorted). And one more thing I noticed (though it might be my imagination) - I think these dummy load resistors are heating up much faster on the non-working PSU. On the good PSU it takes about 30s for them to get hot, on the bad one it seems to be 15-20 sec...
by exxos
Tue Apr 24, 2018 6:47 pm
Forum: PSU (power supplies)
Topic: TT/Mega STE power supply headaches
Replies: 42
Views: 384

Re: TT/Mega STE power supply headaches

So the base doesn't have 0.6V but the PCB does ? I would try soldering 100K pull down on the base (reconnect the transistor base to the PCB).