L-Adapter

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I can achieve 5.2v for Rpi with either 2 or 3 segments lit. I guess it is down to dissipation?

So does that mean it is 'better ' to go for 5.2v with 3 segments and not 2?

Talema 25va 7v tx

I second jimk04's question and guess people are busy soldering...

When you can reach a Vout goal based more on the LEDs contribution than the trimmer's contribution, prefer the first way. Because it keeps the voltage source's impedance lower than the second way. No it has nothing to do with dissipation in sink mounted semiconductors. Your transformer does not have that high a secondary. Which is good for cooler sinks when the load is cruising. But also make sure its not marginal. Check that during your hardest loading current peaks. The Vin-Vout DC voltage (also measurable across D11) should never be too little because of strong momentary losses by the Tx, bridge, ripple voltage. No less than 2.5V DC across.
 
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Still OK after the earthquake Salas?

Apologies....the news of earthquakes have eluded me....been in a bubble for a few days


Hi fi is nothing as long as everyone is well.

It was a well felt, because local and of shallow depth origin, but not catastrophic quake. As the first days pass, that short fault's snap energy has been normally dissipating by many follow up small quakes. 90% of them only felt by instruments. If the dissipation's profile continues like that its very possible that a large event won't be repeated any soon. But it takes more time for such trends to also prove scientifically acceptable.

See, settling time and dissipation are not only happening in regulators. ;)
 
I have built my first L-Adapter on perfo board the last two week and have since been testing it on a 9V stand alone digital player, 12V T-Amp and my 20V laptop which is used as a music server.

All of them worked very well and exhibited low noise floor and never felt like running out of steam.

The LA is a really nice PSU for digital systems.

The digital player is also being tested with a UBiB for comparison and I hope to be able to report my finding later.
 
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L adapters powering Rpi and Ian Isolator

So I have my 2 boards built and tested and running nicely at 5.2v unloaded.
One powers the Pi and one powers the DAC board. Probably a little overkill amperage wise for the DAC but I am waiting on other components to build other psu for there.
I had a noise issue when I introduced the Isolator when powering with single 5v so I will try this later today and see how we get on.
 

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Sounds mega!
The noise issue I have pinned down to a sampling rate thing within Moode....but the psus have really quieted down the background. I have a niece lodging whilst their house purchase goes through and as a nurse on night shift she is currently sleeping so haven't had chance to listen at high levels....but so far very pleased
Thanks again Salas and Tea
 
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Listened to it all tonight for a good while.
Tpa3255 into Tang band w3 871 in 5 litre BR.
The back ground noise level has dropped dramatically and the resolution and depth of bass is also much clearer.
I am not good at portraying my thoughts on what I hear ....but this is a massive improvement on what I was listening to before with the Rpi smps.
And I only have a lowly PCM5122 Dac.
 
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diyAudio Chief Moderator
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It seems your gear really benefited from those PSUs. Good decision to combine, strong result. Congrats and happy listening. The L-A PSUs are going to remain useful for a long while, not only for that particular combination but on various and future gear also, due to their wide voltage and power range compatibility. Good to have them in your arsenal.
 
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So I have my 2 boards built and tested and running nicely at 5.2v unloaded.

One powers the Pi and one powers the DAC board. Probably a little overkill amperage wise for the DAC but I am waiting on other components to build other psu for there.

I had a noise issue when I introduced the Isolator when powering with single 5v so I will try this later today and see how we get on.



What is it which is between pi and dac?