I am interested in replacing ACA with ACAmini to reduce a bit heat dissipated in my 4-channel amp (2xF5 + 2xACA) which currently is borderline in the Summer time. However I would need a pcb for each channel to be separate and in a smaller footprint, (even height is limited in my amp to OAH = 1.5inch). the chances are I will have to make that pcb myself but I am too busy right now. Here are the pictures of the inside of the amp where ACA board(s) (one on each side) are mounted under P.Daniel F5 board(s). The amp has Papa's dual mono regulated PS from Zen v5 article ( rails ended up a bit lower at +/-22.7V):
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Very good news, I am looking forward!Since the ACA mini seems to be a success, Jason has agreed to bring the kit
into the store, so we will make preparations to put it there.
I wish the very best for the new year!
Franz
May I ask which brand 520/9520 will be used in the kits? I don't expect to see Harris parts, or do you have thousands of those in store as well!?
🤔
Which is a vibration-sensitive time bomb, waiting and preparing to suddenly vaporize your amplifier. Pause and consider one of these links
THE FIRST LINK:
https://www.jameco.com/z/2012JH-R-Jameco-Valuepro-Shorting-Block-with-Black-Tab-0-1-_152671.html
THE SECOND LINK:
https://www.amazon.com/ZYAMY-2-54mm-Standard-Circuit-Connection/dp/B077957RN7
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I measured the Harris irf520 I received yesterday with a Mega 328 transistor tester. The junction capacitance is in the range of 934pf to 975pf and a gate to threshold voltage (Vth) in the 4.1v and 4.2v range. These are the two parameters the 328 gives me.
The parts I measured seems on the high side for the gate to to threshold voltage with the data sheet listing 4v as the maximum.
I don't see a specification for junction capacitance on the data sheet.
I guess my next step is to test for Vgs (a procedure I've never done before).
The parts I measured seems on the high side for the gate to to threshold voltage with the data sheet listing 4v as the maximum.
I don't see a specification for junction capacitance on the data sheet.
I guess my next step is to test for Vgs (a procedure I've never done before).
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Fantastic!Since the ACA mini seems to be a success, Jason has agreed to bring the kit
into the store, so we will make preparations to put it there.
Since the ACA mini seems to be a success, Jason has agreed to bring the kit
into the store, so we will make preparations to put it there.
I tested and selected all the parts for Vgs or Idss to make sure operation would be achieved within the range of the pots.
The Harris parts were very consistent, which is one reason I prefer them.
The Harris parts were very consistent, which is one reason I prefer them.
Mark is just joking. There is no amplifier reliability aspect to that connection.
OTOH, everyone knows that aluminum foil will spoil the cow's milk.
OTOH, everyone knows that aluminum foil will spoil the cow's milk.
Anybody interested in taking a video of theirs in action? I'd love to hear it. Can't wait to order one for myself. Do we know what the store cost will be?
So I measured all the IRF520's for Vgs at 5ma and got a range in the 3.50V to 3.56V. I'm doing all this testing to authenticate them as Harris parts, but does what Iv'e done so far prove they are genuine?
Should I get the cryogenically treated jumpers? I heard that they will quantum entangle the 3rd and 4th harmonics in the 5th dimension resulting in an "Age of Aquarius". Of course aluminum foil is more D.I.Y.
Don't let it vibrate loose and fall onto other components, where it can create a short circuit with disastrous consequences.
The new jumpers fit tightly and are unobtrusive. Plus I have a bag of them if I lose another. The included jumpers are quite loose and easy to lose.
they seem good to me. The appearance matches mine. Looks like 2022 has started well.
Ive got mine built, but I am having trouble with biassing - V0 is at 11.8v when the pots are all the way counterclockwise, and I cant get VB above 0.004v.
Any thoughts on what would cause this?
Any thoughts on what would cause this?