Please feel welcome and enthusiastically invited to create a PCB which implements your design idea. DiyAudio members would certainly benefit from having additional choices! Especially if yours results in a physically smaller board, or a significantly cheaper total parts cost. You might choose to eliminate some features of H9KPXG that you think are worthless; or to add new features that you think are sadly lacking; since you're doing a complete redesign from the ground up anyway. Maybe you'd like to add a capacitive proximity sensor capability, letting the user get rid of the on-off button entirely. It's your design, allow it to reflect your unique vision.
Here's my simple ON/OFF power solution using a momentary pushbutton switch/low voltage standby powered.
Works perfectly and uses a minimum of components.
If desired, a 555 timer can be implimented to make a "countdown" switch for a second relay.
Works perfectly and uses a minimum of components.
If desired, a 555 timer can be implimented to make a "countdown" switch for a second relay.
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This one uses a micro controller and costs less than building one.
12V Bond Bistable Relay Car Modification Switch Start Stop Self-Locking Module K | eBay
Mark's design has soft start though. Neither yours or this one do.
Yes, however I was just contributing a simple on/off approach that uses a low voltage/low current momentary pushbutton design to control a main power relay.
With an additional 4017, along with a simple 555 timer, the circuit could activate a second relay after a time delay used in soft-start application.
I would gather that parts and layout would be much less involved then the OP's design.
Grounding question
I have two boards I am going to use in Aleph J monoblocks I am building (thank you Scott). I would like to run a cable from the switch pads on each H9KPXG pcb to a dpdt switch located in a separate box placed near my preamp.
I have two questions:
First: Should my cable just have two wires (V and return) or should I have a third ground wire connecting the chassis (of 1 or both?) of the Aleph Js to the box? I do not want to introduce ground loops and I do not think it would be necessary, but I really have no idea.
Second: I was thinking of using a 5V relay for my switch in the box and powering it with an iPhone charger plugged into the switched outlet of my preamp. This way when I turned on the preamp the Aleph Js would also be turned on. (Would something like this https://www.mouser.com/ProductDetail/Panasonic/JW2SN-DC5V/?qs=HLLy2pIPwuus9vgayzgjwA== work?) (or maybe this one https://www.mouser.com/ProductDetail/TE-Connectivity-PB/R10-E1X2-V28/?qs=zPqOFFyn9moYhWGf%2BHi/5A== (it uses less current for the coil)) Does anyone see any problem with doing that?
Thanks,
Jazzzman
I have two boards I am going to use in Aleph J monoblocks I am building (thank you Scott). I would like to run a cable from the switch pads on each H9KPXG pcb to a dpdt switch located in a separate box placed near my preamp.
I have two questions:
First: Should my cable just have two wires (V and return) or should I have a third ground wire connecting the chassis (of 1 or both?) of the Aleph Js to the box? I do not want to introduce ground loops and I do not think it would be necessary, but I really have no idea.
Second: I was thinking of using a 5V relay for my switch in the box and powering it with an iPhone charger plugged into the switched outlet of my preamp. This way when I turned on the preamp the Aleph Js would also be turned on. (Would something like this https://www.mouser.com/ProductDetail/Panasonic/JW2SN-DC5V/?qs=HLLy2pIPwuus9vgayzgjwA== work?) (or maybe this one https://www.mouser.com/ProductDetail/TE-Connectivity-PB/R10-E1X2-V28/?qs=zPqOFFyn9moYhWGf%2BHi/5A== (it uses less current for the coil)) Does anyone see any problem with doing that?
Thanks,
Jazzzman
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Guess?? The silkscreen AND the pcb itself is marked!
Silkscreen has A and K printed on the LED pads, and the solder pads themselves are square and circular, square is positive. (just like the capacitors)
I am actually talking about the wires from the switch LED. But, I am glad to see so many boards now with the square pads for the (+) for parts. That does take most of the guessing out.
And, yes, the board is quite well marked. The switch I am using came with a computer PC wiring harness, which I cut short, removing the marked ends. I did be sure to distinguish the power switch pair from the LED pair. Since I could no longer read the tiny indented marks on the switch LED tabs, I knew that the switch pair did not matter how connected. I figured I could swap the leads to the LED if it did not light up. Then I did not have to unmount the switch to try and read the dang tiny marks with my old eyes.
DO NOT depend on square vs round! It is completely arbitrary and could be used in both (opposite) orientations on the same PCB. In fact I think I might make my next few boards with all-square pads just to thwart people who use hole shape as a crutch. Don't do it!!
Instead, use your brain, use the schematic, use your DVM on continuity buzzer mode. One of the LED holes will have electrical continuity to the other component leads where the LED Anode (positive terminal) is connected. The schematic tells you what the LED Anode should be connected to. Buzz it out with your continuity tester and verify that Pad_X is connected everywhere LED_Anode is supposed to connect. If so then Pad_X is LED_Anode.
And oh by the way, the boards I lay out have the anodes of diodes marked with an "A" in top silkscreen, and the cathodes of diodes are marked with a "K". Even Light Emitting Diodes. I do this as a quick reminder to myself when stuffing boards: Anode goes here, Cathode goes there. If you see "A" and "K" on silkscreen, you can rely upon that. Just don't imagine that square pad or round pad means anything special -- you'll get burned.
Instead, use your brain, use the schematic, use your DVM on continuity buzzer mode. One of the LED holes will have electrical continuity to the other component leads where the LED Anode (positive terminal) is connected. The schematic tells you what the LED Anode should be connected to. Buzz it out with your continuity tester and verify that Pad_X is connected everywhere LED_Anode is supposed to connect. If so then Pad_X is LED_Anode.
And oh by the way, the boards I lay out have the anodes of diodes marked with an "A" in top silkscreen, and the cathodes of diodes are marked with a "K". Even Light Emitting Diodes. I do this as a quick reminder to myself when stuffing boards: Anode goes here, Cathode goes there. If you see "A" and "K" on silkscreen, you can rely upon that. Just don't imagine that square pad or round pad means anything special -- you'll get burned.
But, what is soft unstart actually?
Good Morning Mark and everyone
Firstly, of course, many thanks to Mark for sharing his immense knowledge, and for all the thorough and entertaining explanations!
I’m not quite through all of it, but I tried both reading through and specific search to no avail: what is actually the soft unstart (how does it work and why should I have it)?
Thank you!
I wish an enjoyable say to everyone!
d.)
Good Morning Mark and everyone
Firstly, of course, many thanks to Mark for sharing his immense knowledge, and for all the thorough and entertaining explanations!
I’m not quite through all of it, but I tried both reading through and specific search to no avail: what is actually the soft unstart (how does it work and why should I have it)?
Thank you!
I wish an enjoyable say to everyone!
d.)
If you stuff and solder an H9KPXG PCB according to the schematic and the Detailed Parts List, you'll get soft unstart whether you want it or not. If you really, really don't want soft unstart you'll need to devise a modification to the circuit design. It will probably require a few "cuts and jumps" to the copper traces of the PCB, but if you're both clever and lucky, no new components. I offer my best wishes for successful completion, but I do not offer any assistance; in my opinion soft unstart is a good idea not a bad one, and I won't participate in disabling it.
Soft unstart describes the gradual and safeguarded procedure used in H9KPXG during turn-off. The big idea is to turn the triac on and leave it on, before, during, and (importantly) after opening the relay contacts. Thus the triac + ICL appear in shunt, across the relay contacts. If the relay contacts bounce (and they usually do, when opening), the triac+ICL damps ("quenches") any possibility of contact arcing during bounce(s). Finally, after a delay time much longer than the longest possible contact bounce, the triac shuts off and current to the load (transformer primary) is zero.
Soft unstart lengthens the service life of the relay contacts, by preventing contact arcing during shutoff.
There's a diagram of this, figure #5 in post 1 of this thread. Look for the oval shaped bubbles and arrows.
Soft unstart describes the gradual and safeguarded procedure used in H9KPXG during turn-off. The big idea is to turn the triac on and leave it on, before, during, and (importantly) after opening the relay contacts. Thus the triac + ICL appear in shunt, across the relay contacts. If the relay contacts bounce (and they usually do, when opening), the triac+ICL damps ("quenches") any possibility of contact arcing during bounce(s). Finally, after a delay time much longer than the longest possible contact bounce, the triac shuts off and current to the load (transformer primary) is zero.
Soft unstart lengthens the service life of the relay contacts, by preventing contact arcing during shutoff.
There's a diagram of this, figure #5 in post 1 of this thread. Look for the oval shaped bubbles and arrows.
Thank you, Mark
Somehow you got me right and wrong:
I just did not understand what the soft unstart (like this expression very much) actually does. Now I have a feeling like I kinda do.
I really really do not not want it in my circuits. [emoji4] (but I haven‘t it yet, because there‘s a diyaudiostore softstart ... yet.
And please don‘t get me wrong about me trying to be ironic—I enjoy these injected glimpses of irony (sarcasm, sometimes?) and I especially appreciate that you are sharing all that stuff.
Well, no. I had an idea that soft unstart probably was as good to the shutdown-process as the softstart is to the start-/ loadingprocess. Just like i prefer to shut down a computer by using the appropriate procedure instead of just pulling the plug. [emoji3526]
diyAudio members ggetzoff , 6L6 , A321Drvr , and no doubt many more,
will be able to explain the original meaning of the term "un-start", which I shamelessly appropriated from the engineering lexicon of the Pratt and Whitney J58 turbojet , and its installation into the Oxcart airframe by project manager Clarence "Kelly" Johnson (no relation).
You've got ten clicks of Tri Ethyl Borane, ten and only ten. Manage your resources wisely.
_
will be able to explain the original meaning of the term "un-start", which I shamelessly appropriated from the engineering lexicon of the Pratt and Whitney J58 turbojet , and its installation into the Oxcart airframe by project manager Clarence "Kelly" Johnson (no relation).
You've got ten clicks of Tri Ethyl Borane, ten and only ten. Manage your resources wisely.
_