Since I have a power switch before this board, I brought my mains directly into SW2 and Neutral. C1 becomes superfluous. Try mains directly into SW2 see what happens. Obviously have a fuse on the mains IEC before the circuit.
Dirk: you needed to have a SPST switch in between SW1 & SW2. See page 13. It’s the older board but you can figure out the switch wiring onto the new board.
If you intend to go directly into SW2 remove C1 so there’s nothing flowing back into Live/SW1.
Pete
https://www.diyaudio.com/media/build-guides/diyaudio-softstart-build-guide-v1.0.pdf
If you intend to go directly into SW2 remove C1 so there’s nothing flowing back into Live/SW1.
Pete
https://www.diyaudio.com/media/build-guides/diyaudio-softstart-build-guide-v1.0.pdf
questions arise...
Hiya!
I was looking around for information about rectifiers (prasi!), softstart (Mark!) and did some research this weekend (surfing diyaudio instead of soldering, that is). Questions arose:
1) Should the capacitor-loading be specially addressed?
2) Bleeder resistors add hum? (*)
and, since I haven't yet digested all that,
3) Are these questions senseless?
*) I found an old thread, "Soft start circuit design and other psu issues", where AndrewT made a startling statement: Ouch.
Are them R9 R10? Is this something to take into consideration? (If a very slow cap-bleed after shutdown was acceptable...)
Hiya!
I was looking around for information about rectifiers (prasi!), softstart (Mark!) and did some research this weekend (surfing diyaudio instead of soldering, that is). Questions arose:
1) Should the capacitor-loading be specially addressed?
2) Bleeder resistors add hum? (*)
and, since I haven't yet digested all that,
3) Are these questions senseless?
*) I found an old thread, "Soft start circuit design and other psu issues", where AndrewT made a startling statement: Ouch.
Are them R9 R10? Is this something to take into consideration? (If a very slow cap-bleed after shutdown was acceptable...)
5W - Hot as hell
Hello guys, I built this circuit validated my wiring but the 5W resistors are becoming crazy hot
. I made sure I have the right ones (5w wirewound 180R - white rectangle). I'm connected directly to SW2 so I removed C1. Other than this, it's all standard. The light comes on. The system works but it gets so hot I saw smoke coming out of those resistors.
Any idea what could be wrong?
Hello guys, I built this circuit validated my wiring but the 5W resistors are becoming crazy hot
. I made sure I have the right ones (5w wirewound 180R - white rectangle). I'm connected directly to SW2 so I removed C1. Other than this, it's all standard. The light comes on. The system works but it gets so hot I saw smoke coming out of those resistors.Any idea what could be wrong?
Hello guys, I built this circuit validated my wiring but the 5W resistors are becoming crazy hot
Any idea what could be wrong?
Northox, I’m presuming you’re running 220VAC, correct? If the board is disconnected from anything past XFR1&2 do the resistors still get hot?
Pete
S1 and S2 are connected together on the board. Trace the board to convince yourself.
There is no direct ground connection to the board; you connect the neutral and hot (fused hopefully) only. The earth ground from your AC inlet should be attached to your chassis. For more information about that, there is a really fantastic and detailed article that explains your options and things to consider:
Audio Component Grounding and Interconnection
--Tom
There is no direct ground connection to the board; you connect the neutral and hot (fused hopefully) only. The earth ground from your AC inlet should be attached to your chassis. For more information about that, there is a really fantastic and detailed article that explains your options and things to consider:
Audio Component Grounding and Interconnection
--Tom
Mark, in your very helpful post (#291) on the pros and cons of a soft start board vs thermistors you state that Nelson Pass recommends use of a power supply using thermistors. Do you (or does anyone else) know whether there's a reason for this related to the operation of an Aleph J (which I'm currently building)? I have built a DIY audio soft start which I'd like to use, but if thermistors really are better in this instance I'll use them.
A second question: I read in an earlier post that with 240AC (which is what we have here) it was found that a value of 220uF for C2 did not allow the relay to operate, and that 330uF worked. I currently have the 1uF cap specified in the BOM. Is this a potential problem?
Any help appreciated!
A second question: I read in an earlier post that with 240AC (which is what we have here) it was found that a value of 220uF for C2 did not allow the relay to operate, and that 330uF worked. I currently have the 1uF cap specified in the BOM. Is this a potential problem?
Any help appreciated!
Here‘s my 2c (very nontechnical...)
Thermistors are the easiest by far. Disadvantage is that it eats up a little bit of current and gets awfully hot while the amp is running.
The softstart circuit is a circuit with many more parts, but I prefer it—the circuit gets out of the way once it has accomplished its duty.
I am built my straight after the bom and buildguide, and in 230V world its clicking after a second or so...
Just re-read my reply. Sorry for writing barely english of sorts... 
Just one more comment: Although toecutter's soft-start board perfectly works, there's an alternative around giving you a few more options:
Mark Johnson's H9KPXG
It was developed with a different focus (connecting a low-power switch) but provides the soft-start too... so you might be better off with this one if you aren't satisfied with the usual AC-switches...
Just one more comment: Although toecutter's soft-start board perfectly works, there's an alternative around giving you a few more options:
Mark Johnson's H9KPXG
It was developed with a different focus (connecting a low-power switch) but provides the soft-start too... so you might be better off with this one if you aren't satisfied with the usual AC-switches...