Hi guyz
I got it, amp is working! But i got some oscilation on output. I had to change the value of some resistors, like R32/33 to 1.9k, Vcc jumps to 82V, on each R32/33 I have 25,5mV. And connected signal gnd direct to main capacitors. R20 changed to 330ohm, on 2sk1058/2sj162 is almost 100mA on each, I do not have enough transistors to match them perfectly, pair has 80mA, some 104mA. I have ordered 15 pairs yesterday, so it will be work to do. Dc out about 1mV. Vas transistors on same litle heat sink.
No signal connected, heat sink connected to ground.
Have somebody have same oscilations?
I got it, amp is working! But i got some oscilation on output. I had to change the value of some resistors, like R32/33 to 1.9k, Vcc jumps to 82V, on each R32/33 I have 25,5mV. And connected signal gnd direct to main capacitors. R20 changed to 330ohm, on 2sk1058/2sj162 is almost 100mA on each, I do not have enough transistors to match them perfectly, pair has 80mA, some 104mA. I have ordered 15 pairs yesterday, so it will be work to do. Dc out about 1mV. Vas transistors on same litle heat sink.
No signal connected, heat sink connected to ground.
Have somebody have same oscilations?
Re: Golmund clone
Andrew
i see only the green yelow cable to continue to soft start pcb with SCHAFNER FN 405-6/02 filter.
I don't now if connected to mains ground. (Probably yes)
The other cable red yellow came from inside the box trafo and connect to star ground i think that is isolated from box and connect only on heatsink.
This conclusion comes from my measurements.
When I connect my multimeter in ~ mode between neutral 0 PSU and heatsink
i measure 10-12V AC The only way to eliminate this is to connect neutral 0 PSU
on heatsink.When i connect the main earth ground on heatsink i have ringing on my scope.
Regards Nikos
Andrew
i see only the green yelow cable to continue to soft start pcb with SCHAFNER FN 405-6/02 filter.
I don't now if connected to mains ground. (Probably yes)
The other cable red yellow came from inside the box trafo and connect to star ground i think that is isolated from box and connect only on heatsink.
This conclusion comes from my measurements.
When I connect my multimeter in ~ mode between neutral 0 PSU and heatsink
i measure 10-12V AC The only way to eliminate this is to connect neutral 0 PSU
on heatsink.When i connect the main earth ground on heatsink i have ringing on my scope.
Regards Nikos
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Re: Golmund clone
Andrew
i see only the green yelow cable to continue to soft start pcb with SCHAFNER FN 405-6/02 filter.
I don't now if connected to mains ground. (Probably yes)
The other cable red yellow came from inside the box trafo and connect to star ground i think that is isolated from box and connect only on heatsink.
This conclusion comes from my measurements.
When I connect my multimeter in ~ mode between neutral 0 PSU and heatsink
i measure 10-12V AC The only way to eliminate this is to connect neutral 0 PSU
on heatsink.When i connect the main earth ground on heatsink i have ringing on my scope.
Regards Nikos
Andrew
i see only the green yelow cable to continue to soft start pcb with SCHAFNER FN 405-6/02 filter.
I don't now if connected to mains ground. (Probably yes)
The other cable red yellow came from inside the box trafo and connect to star ground i think that is isolated from box and connect only on heatsink.
This conclusion comes from my measurements.
When I connect my multimeter in ~ mode between neutral 0 PSU and heatsink
i measure 10-12V AC The only way to eliminate this is to connect neutral 0 PSU
on heatsink.When i connect the main earth ground on heatsink i have ringing on my scope.
Regards Nikos
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AndrewT is referring to wiring standards that apply to commercial appliances in the UK. Similar ones now generally apply in the EU under IEC 60466. They are not universal since individual standards globally are often only harmonized i.e. the same where it is compatible with existing standards.
Electrical wiring - Wikipedia, the free encyclopedia
IEC 60446 - Wikipedia, the free encyclopedia
More importantly for DIY readers though, is that we don't mislead others by inappropriate use of even our own local standard mains appliance wiring codes, on which their understanding and very lives may depend. This is a difficult matter for North and South American members, whose colour codes don't necessarily include striped wiring and have different AC colours as well.
Electrical wiring - Wikipedia, the free encyclopedia
IEC 60446 - Wikipedia, the free encyclopedia
More importantly for DIY readers though, is that we don't mislead others by inappropriate use of even our own local standard mains appliance wiring codes, on which their understanding and very lives may depend. This is a difficult matter for North and South American members, whose colour codes don't necessarily include striped wiring and have different AC colours as well.
Golmund clone
The two cables red -yellow came from star earth ground inside the box trafos and connect the each metal box of supplies to star earth ground and its not isolated from box .
The heatsink not conected to 0 neutral of PSU.
The two cables red -yellow came from star earth ground inside the box trafos and connect the each metal box of supplies to star earth ground and its not isolated from box .
The heatsink not conected to 0 neutral of PSU.
Thanks for the two links.AndrewT is referring to wiring standards that apply to commercial appliances in the UK. Similar ones now generally apply in the EU under IEC 60466. They are not universal since individual standards globally are often only harmonized i.e. the same where it is compatible with existing standards.
Electrical wiring - Wikipedia, the free encyclopedia
IEC 60446 - Wikipedia, the free encyclopedia
More importantly for DIY readers though, is that we don't mislead others by inappropriate use of even our own local standard mains appliance wiring codes, on which their understanding and very lives may depend. This is a difficult matter for North and South American members, whose colour codes don't necessarily include striped wiring and have different AC colours as well.
They go to prove that yellow/green is universally recognised as PE.
Austalia even prohibits yellow/green for any of the line (live) colours
The red/yellow wires connects the two transformer chassis and the L-profile/heatsink to the chassis at the star ground point to the right of the L profile since they are all isolated from the chassis with white rubber or teflon isolators. One red/yellow wire and one green/yellow (mains Earth) wire is then connected to the ground lifting switch.
Hope this helps
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Re: Golmund clone
Ηi Tommy
Yes it helps
I had already make all these but at the end i dont connect the L profile at the ground because gives me ringing.
But what is the benefit of ground lifting switch??
Someone says (((The ground lift is useful in cases where the chassis of the amps are connected to earth ground and you have multiple amps in a metal rack. All but one of the amps in a rack should have the ground lifted so that there is only one path to ground. In other words: use this switch to prevent ground loops.)))
Ηi Tommy
Yes it helps
I had already make all these but at the end i dont connect the L profile at the ground because gives me ringing.
But what is the benefit of ground lifting switch??
Someone says (((The ground lift is useful in cases where the chassis of the amps are connected to earth ground and you have multiple amps in a metal rack. All but one of the amps in a rack should have the ground lifted so that there is only one path to ground. In other words: use this switch to prevent ground loops.)))
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Re: Golmund clone
Safety ground is the third wire in your AC power supply, usually green or green/yellow wire. For safety all metal parts of the equipment are connected to safety ground.
Audio ground appears at the audio inputs and outputs. It is not necessary for audio ground and safety ground to be connected together. In many situations the connection of audio ground and safety ground causes ground loops which pickup 50/60Hz interference.
Ted
It is called ground lift because it is disconnection switch. In the normal position of the switch the audio ground is connected to the safety ground. When the swich is in the ground lift position audio ground is not connected to safety ground.
Safety ground is the third wire in your AC power supply, usually green or green/yellow wire. For safety all metal parts of the equipment are connected to safety ground.
Audio ground appears at the audio inputs and outputs. It is not necessary for audio ground and safety ground to be connected together. In many situations the connection of audio ground and safety ground causes ground loops which pickup 50/60Hz interference.
Ted
NEVER use ground lift switches in DIY as you will compromise on safety when easy mistakes are made. Mistakes like disconnecting the ground path to the chassis for instance. PE was invented with a good reason: protecting you and your family from electrocution.
Just build stuff correctly wired and use PE as intended. Use of insulated RCA plugs is mandatory.
Just build stuff correctly wired and use PE as intended. Use of insulated RCA plugs is mandatory.
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Youre living in old ages.
Nowadays we have RCD:s (Residual Current Breakers) in almost every home.
Quite OK to break the ground connection with no concern from safety.
The "ground" is today mostly used to avert disturbances from mains interferencies though interference filters.
Johan
Why do you think the RCD's are failing??
Still the PE (Protection Earth_Netral connection) only makes the reliance of the in line fuse protection, in the range of 5 to, 15 Amps to break the current.
Thats really deadly!!
The RCD "feels" the offset current in the live/neutral of only about 15mA to cut the circuit.
Johan
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