Is it possible to unwind a transformer 35volt and 750 VA?
Which value do I unwind it to? I have speakers with 8 ohm impedance drivers, maybe 4 ohm tweeters.
Also trying to put this LM3875 chip amp from chipamp.com together, not 100% sure how. Any good links? chipamp.com is no longer a website.
http://diyaudioprojects.com/Chip/Beast/nigc_kit-users_guide.pdf
https://audiosector.com/wp-content/uploads/2019/01/LM3875-kit-instructions.pdf
I put a chipamp LM3875 kit together 20 years ago. Sounded really good with Eton 8-800 2-ways; LPG tweeter.
I also have 171 VA 28.5 VDC transformer, but it doesn't look as nice.
Should I get a RFI power plug for this amp?
I was hoarding some for years, but I think I threw them out.
I like the finished product to have nice parts.
Which value do I unwind it to? I have speakers with 8 ohm impedance drivers, maybe 4 ohm tweeters.
Also trying to put this LM3875 chip amp from chipamp.com together, not 100% sure how. Any good links? chipamp.com is no longer a website.
http://diyaudioprojects.com/Chip/Beast/nigc_kit-users_guide.pdf
https://audiosector.com/wp-content/uploads/2019/01/LM3875-kit-instructions.pdf
I put a chipamp LM3875 kit together 20 years ago. Sounded really good with Eton 8-800 2-ways; LPG tweeter.
I also have 171 VA 28.5 VDC transformer, but it doesn't look as nice.
Should I get a RFI power plug for this amp?
I was hoarding some for years, but I think I threw them out.
I like the finished product to have nice parts.
22-0-22v(AC) is fine!
A Complete Guide to Design and Build a Hi-Fi LM3886 Amplifier - Circuit Basics
A Complete Guide to Design and Build a Hi-Fi LM3886 Amplifier - Circuit Basics
Is it possible to unwind a transformer 35volt and 750 VA?
Please be careful doing this. From personal experience I found removing too much secondary can make the transformer primary work more like an inductor, i.e. a dead short. May I suggest you ask about this in the Power Supplies forum here, specifically Tony Tecson?
[The Wayback archive chipamp]Chipamp Electronics
Please be careful doing this. From personal experience I found removing too much secondary can make the transformer primary work more like an inductor, i.e. a dead short. May I suggest you ask about this in the Power Supplies forum here, specifically Tony Tecson?
[The Wayback archive chipamp]Chipamp Electronics
Removing a section of a transformer secondary reduces coupling between prim-sec, and leads to an increased leakage inductance.
This works in effect as a separate inductance in series with the transformer which leads to a voltage drop when current is passing, and lower secondary voltage.
But it is not a short, unless you damage windings when unwinding.
I am not sure about the 35VDC transformer, a transformer produces AC but is it 35VAC or 24VAC rectified to DC?
The actual removal of windings can be more or less straightforward. I am currently doing it on a 2000VA transformer with 12 secondaries ranging from 5 to 80V, various amperage while trying to save a few. It doesn't help that the transformers outer insulation is varnish coated paper or cotton gauze. But hey, you gotta have a hobby
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