ACA with 24 V supply is a step up.
Regards
Thiago
do you think these would do the job they seem a good price?
https://www.amazon.co.uk/SJP-LIGHT®...471512857&sr=8-3&keywords=24v+power+supply+5a
or would I be better off with a couple like this
https://www.amazon.co.uk/dp/B01DDX7JM2?psc=1 KeerSen DC 24V 5A 120W Switching Power Supply Regulated Transformer w/ Short Circuit and Over Current Protection (24V5A)
??
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hi guys,
I hope you can help me answer this simple question regarding Keratherm MOSFET insulators.
Do we use both the pink pad and the brown pad (2 layers) to insert b/w the heatsink and the mosfet or we only use the pink pad and discard the brown pad as the pink pad can be peeled off from the backing brown pad.
Please let me know the answer ASAP
I actually finished putting the board and soldered them to both mosfet and I only use 1 single pink pad for the thermal insulator as shown in the illustrated guide. But when I watch the Youtube video from TekThing, they use both layers (Pink+Brown) for each mosfet. That's where my confusion comes in
Please see the image attached for my definition of PINK and BROWN pads (Please excuse me if I don't use the right technical term for these thermal insulator pads)
Pink pad
https://www.dropbox.com/s/r82xh1aclieslc3/PINK%20PAD.jpg?dl=0
https://www.dropbox.com/s/zed7uexdbwsvwj2/BROWN%20PAD.jpg?dl=0
Thanks,
Tom
I hope you can help me answer this simple question regarding Keratherm MOSFET insulators.
Do we use both the pink pad and the brown pad (2 layers) to insert b/w the heatsink and the mosfet or we only use the pink pad and discard the brown pad as the pink pad can be peeled off from the backing brown pad.
Please let me know the answer ASAP
I actually finished putting the board and soldered them to both mosfet and I only use 1 single pink pad for the thermal insulator as shown in the illustrated guide. But when I watch the Youtube video from TekThing, they use both layers (Pink+Brown) for each mosfet. That's where my confusion comes in
Please see the image attached for my definition of PINK and BROWN pads (Please excuse me if I don't use the right technical term for these thermal insulator pads)
Pink pad
https://www.dropbox.com/s/r82xh1aclieslc3/PINK%20PAD.jpg?dl=0
https://www.dropbox.com/s/zed7uexdbwsvwj2/BROWN%20PAD.jpg?dl=0
Thanks,
Tom
If I order a kit today will the circuit board have a space R15? If not is the resistor used at one of the legs of Q3 included?
I can't say about inclusion of the resistor in the kit, but I have a
recent-vintage ACA board and it has a space for R15.
Dennis
You can tin them if you like. It's not going to hurt anything. I don't.
As for speakers and little amps, more sensitivity is always better. As is a smooth impedance curve.
Once you hear these amps (totally awesome) you will really want one of the bigger First Watts, and build an Alpeh J or BA-3 or F6, etc...
As for speakers and little amps, more sensitivity is always better. As is a smooth impedance curve.
Once you hear these amps (totally awesome) you will really want one of the bigger First Watts, and build an Alpeh J or BA-3 or F6, etc...
Well you need the trimmer potentiometer to adjust the bias voltage to 10V as per the instructions. If you had a pot to use temporarily you could adjust it then measure the value and then insert a resistor (or a combination) or maybe start with a resistor in around a 2.5k value. Not sure if a smaller or larger resistor raises the voltage. You can (carefully) find out. Probably someone will say and once you know that you can proceed conservatively.
THe suggested trimmer resistor is 5K 0.5w in part list.
Can i use 5K 250mw (1/4w) resistor?
Thanks in advance.
Well you need the trimmer potentiometer to adjust the bias voltage to 10V as per the instructions. If you had a pot to use temporarily you could adjust it then measure the value and then insert a resistor (or a combination) or maybe start with a resistor in around a 2.5k value. Not sure if a smaller or larger resistor raises the voltage. You can (carefully) find out. Probably someone will say and once you know that you can proceed conservatively.
This question stems from my experience with tubes whose bias can change over time. Is that true with MOSFETS or is it a set it and forget it approach?
Best,
Anand.
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