sounds like poor decouppling <<cant spell or do i care
try running a wire from the neg to chassis m8
Murphy Homebase Mains Hum
- dt307
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Re: Murphy Homebase Mains Hum
163dt307-chris
“I fear the day that technology will surpass our human interaction. The world will have a generation of idiots.”
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“I fear the day that technology will surpass our human interaction. The world will have a generation of idiots.”
― Albert Einstein
- sickboy
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Re: Murphy Homebase Mains Hum
That's some cap lol, imagine putting that reverse polarity by mistake, it'd take half your house away!
Wire from neg to chassis actually makes it worse for some reason?
So the switch mode psu creates this noise whether it's in the Murphy case or out, but doesn't create it with other rigs.
A separate external (linear) psu doesn't create any noise at all though, so it looks like that's the route I'm going to have to go. Add a 12v input socket on the rear of the case. Shame to do that but if it makes it useable then so be it
Wire from neg to chassis actually makes it worse for some reason?
So the switch mode psu creates this noise whether it's in the Murphy case or out, but doesn't create it with other rigs.
A separate external (linear) psu doesn't create any noise at all though, so it looks like that's the route I'm going to have to go. Add a 12v input socket on the rear of the case. Shame to do that but if it makes it useable then so be it
Embrace your inner muppet !
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Re: Murphy Homebase Mains Hum
Sometimes switch mode psu's will whistle when there isn't enough load on them.
Try connecting an indicator bulb across the psu and see if that quietens it down.
If so, it might need a permanent load of about 1 amp on it to stop it howling.
A lot of the cheap psu's on eBay are designed to have about full load on them all the time (LED lights etc), so they don't bother too much with the no (or little) load conditions.
A lot of computer psu's are like that also.
Try connecting an indicator bulb across the psu and see if that quietens it down.
If so, it might need a permanent load of about 1 amp on it to stop it howling.
A lot of the cheap psu's on eBay are designed to have about full load on them all the time (LED lights etc), so they don't bother too much with the no (or little) load conditions.
A lot of computer psu's are like that also.
Alan 26FB806
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27.385 LSB, 27.555 USB, 27.78125 FM
Use it or lose it!!!!
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27.385 LSB, 27.555 USB, 27.78125 FM
Use it or lose it!!!!