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Old 28th April 2006, 03:26 PM   #11
jleaman is offline jleaman  Belgium
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Quote:
Originally posted by Mad_K
Are you using R0? What value?

R0? huh
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Old 28th April 2006, 04:30 PM   #12
khaho is offline khaho  Finland
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Quote:
Originally posted by jleaman
And here is a link to my crappy drawing to how it is all connected.


http://jleaman.ath.cx/aleph/testing-psusm.jpg
Is -IN really not connected at all ? It should be connected in SE too.
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Old 28th April 2006, 07:50 PM   #13
Mad_K is offline Mad_K  Norway
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Quote:
Originally posted by jleaman



R0? huh

-IN should be connected to SG, but that's not creating a ground loop.
R0 should be 3R3@3W (according to A30 sch) or jumpered.
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Old 28th April 2006, 08:28 PM   #14
jleaman is offline jleaman  Belgium
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Quote:
Originally posted by Mad_K



-IN should be connected to SG, but that's not creating a ground loop.
R0 should be 3R3@3W (according to A30 sch) or jumpered.

I don't understand. and my other mini a's not in this chassi work 100% with out any hum only this one in a chassis.
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Old 29th April 2006, 06:18 AM   #15
jleaman is offline jleaman  Belgium
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Ok i did what you suggested MAD_K but there is still hum. It sounds like it is more lighter but less deeper now. Now to test and see if i should be shielding the interconnect cable now from the pcb to the rca jack..
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Old 29th April 2006, 10:00 AM   #16
Mad_K is offline Mad_K  Norway
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So what value did you use for R0?. Also, do you use a 10R/5A thermistor from GND (on psu board) to the chassis/Protective Earth? Both of these components are used to supress ground loops.
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Old 29th April 2006, 05:15 PM   #17
jleaman is offline jleaman  Belgium
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Quote:
Originally posted by Mad_K
So what value did you use for R0?. Also, do you use a 10R/5A thermistor from GND (on psu board) to the chassis/Protective Earth? Both of these components are used to supress ground loops.

R0 is = 3.0Ohm @ 3 watt

and i have a thermister on the ac side of the ac plug but not on the gnd i could try one there but i doubt it will do any thing. I have tried removing the ac gnd from the circuit and it does nothing.
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Old 29th April 2006, 11:11 PM   #18
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What if you tried a 'series' ground. Take your ground from the psu to one amp board, and just ground the other amp board at the first amp board...see below. It worked for me on my mini a. Actually, it's the only thing that worked for me.
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Old 30th April 2006, 12:22 AM   #19
jleaman is offline jleaman  Belgium
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Quote:
Originally posted by mpmarino
What if you tried a 'series' ground. Take your ground from the psu to one amp board, and just ground the other amp board at the first amp board...see below. It worked for me on my mini a. Actually, it's the only thing that worked for me.

Where do you want the speakers Ground connected to ?
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Old 30th April 2006, 01:25 AM   #20
Mad_K is offline Mad_K  Norway
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I would have tried to connect SG (RCA GND) to the other side of R0 (near Z4).
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