Teradak Supply Accuracy?

[mourip]

Hi,

 

I just received a Teradak 5v @ 3amp supply to use to power my PPAv2 USB card. I am finding that using my Fluke multi-meter it is putting out 5.2 volts.

 

I hate to nit pick but it seems to me that when one is buying a regulated supply it should be right on the money. I suppose that my meter could be drifting and it is also possible that as long as it is really stable at 5.2 volts the USB card will not care but I am still thoughtful about it.

 

Is my OCD protruding?

 

Any ideas?

 

Best,

 

Paul

[prot]

Hi,

 

I just received a Teradak 5v @ 3amp supply to use to power my PPAv2 USB card. I am finding that using my Fluke multi-meter it is putting out 5.2 volts.

 

I hate to nit pick but it seems to me that when one is buying a regulated supply it should be right on the money. I suppose that my meter could be drifting and it is also possible that as long as it is really stable at 5.2 volts the USB card will not care but I am still thoughtful about it.

 

Is my OCD protruding?

 

Any ideas?

 

Best,

 

Paul

 

5.2V means a 4% deviation. Which is pretty good. I am not aware of any standards but from what I seen, basic regulated PSes have a deviation of about 10%. And 5% is more or less the average ...and a good value. 1% devices exist (at least in theory) but the prices are quite crazy.

You can further investigate but unless you have a friend with the right tools it's gonna be prohibitively expensive: very good multimeters cost >$400 and an oscilloscope even more.

Also, a constant voltage is a pretty good sign.

 

So...yes...you are most prolly worrying too much

 

 

P.S.

dont expect the regulated PS to make major diffs in sound, especially if your PC was optimized and relatively noise free to start with. The reports are wildly exagerated and it depends on many, many, many factors.

[mourip]

Thanks. I appreciate the reply.

 

I had DIY'd a 5v shunt regulator but it was straining at 1 amp. It played music well and I thought bought a tiny bit of improvement but I had a lot of dropouts/buffering. As soon as I hooked my internal HDPlex 5v power supply back up all was well. I think that the PPA needs at least 1 amp, oddly enough as specified on their web site :-)

 

You are probably right. Ones worst fears are never(seldom) realized and my OCD is now back inside the box...

 

Best,

 

Paul

[prot]

...

and my OCD is now back inside the box...

 

Best,

 

Paul

 

That's very good news, glad I was able to help. As you prolly seen in other threads my 'speciality' is actually annoying people

But Christmas is coming, time to be nice(er)

 

Now ... if anyone could take care of my OCD...

[Lowlands]

Most pictures of Teradak PSU internals show regulator boards that can be fine-tuned with a screw driver. Look for a small blue rectangular box with a small copper-flavour screw on top..... Use a good multi meter and allow it to warm up first....

On the other hand, if the PPA works on the 5.2V, you might want to ask Paul first if it matters at all...

[Elberoth]

Voltage should drop to 5v @ rated current draw. With no load voltage is often higher.

[Superdad]

Voltage should drop to 5v @ rated current draw. With no load voltage is often higher.

 

It better not be. Not on a regulated supply. If it does, then the supply is designed wrong.

Our JS-2 puts out the same (whatever the user sets its switches at) at no-load, at 0.5A, and at rated 5A. Of course at the end of a long cable you will have a couple tenths droop, depending upon wire gauge and length (unless using our "sense" circuit to insure exact and quick voltage compensation right at the load).

[mourip]

Voltage should drop to 5v @ rated current draw. With no load voltage is often higher.

 

I emailed Teradak and they said that exactly. 5.2 no-load and 5v with a load. I also emailed Paul Pang and he said that even if it was 5.2 that was fine. My guess is that a stable voltage from a quiet supply is the key part even if the output is not exact.

 

I might adjust it however they put a sticker over the case joint so that they will know if you have opened it. Since the warranty states "walk-in" and they are in Asia and I am in the eastern US I probably will not walk there if I have a problem so opening the case seems like an option :-)

 

These days I either do not buy overseas direct or if I do I just figure that I have no warrany and I will fix it myself. I generally look for equipment made here or at least from a vendor with a US repair agreement.

 

The good news is that the noise floor of my system dropped when I add the supply and I now have better sound...to my ears...more detail and a more analog sound. I believe that it was a worthwhile upgrade and at the price point a very good value.

 

Of course now that I have the 19v/12v HDPlex and the added 5v Teradac I find out that HDPlex now makes a supply with 19v/12/9v/5v which would have been a perfect solution.

 

Thanks to those who have replied!

[sandab]

Hi,

 

I just received a Teradak 5v @ 3amp supply to use to power my PPAv2 USB card. I am finding that using my Fluke multi-meter it is putting out 5.2 volts.

 

I hate to nit pick but it seems to me that w

It might drop to 5.0V under 500mA (or 3A?) load.

 

Always better to have a supply that's slightly high than low.

[Superdad]

It might drop to 5.0V under 500mA (or 3A?) load.

 

That makes no sense. The whole point of a regulated supply is to regulate. If the output voltage sags under load then that load is greater than the supply is rated for (or the supply is rated for more than it is capable of).

[Thiers.prive]

I emailed Teradak and they said that exactly. 5.2 no-load and 5v with a load. I also emailed Paul Pang and he said that even if it was 5.2 that was fine. My guess is that a stable voltage from a quiet supply is the key part even if the output is not exact.

 

Sory I have tried to contact Teradak on there three mail adress no answer? Do you know haw to contact them by anather way or adress. The webste seems old.

Thanks for your helm

[sandyk]

5.2V means a 4% deviation. Which is pretty good. I am not aware of any standards but from what I seen, basic regulated PSes have a deviation of about 10%. And 5% is more or less the average ...and a good value. 1% devices exist (at least in theory) but the prices are quite crazy.

You can further investigate but unless you have a friend with the right tools it's gonna be prohibitively expensive: very good multimeters cost >$400 and an oscilloscope even more.

Also, a constant voltage is a pretty good sign.

 

So...yes...you are most prolly worrying too much

 

 

P.S.

dont expect the regulated PS to make major diffs in sound, especially if your PC was optimized and relatively noise free to start with. The reports are wildly exagerated and it depends on many, many, many factors.

 

Most regulated PSUs have trimmer potentiometers (often 20 turn types) for fine adjustment of output voltage, or carefully selected 1% tolerance voltage setting resistors. Another approach when using 2 resistors for doing this is to aim for a slightly lower output voltage , then fit a suitable higher value resistor in parallel with the lower value resistor of the pair, to get the output voltage to within several millivolts of the desired output voltage. Conversely, if the output voltage is a little too, you can fit a selected much higher value resistor across the higher value resistor of the pair. Perhaps even up to 100 x the value of the higher value resistor.

You can obtain a close tolerance DMM for <$100.

Basic voltage regulated PSUs should be less than 5% from the nominal value. Most I.C. based voltage regulators use adjustable voltage regulators due to their superior ripple rejection, which can be up to 15dB better when a 10uF capacitor is connected between the adjust terminal and the 0 volts line. There is no excuse for an expensive Linear PSU to have an voltage output that isn't within 100mV or so of the desired output voltage, even under the rated continuous load. I would be concerned with a 5V output higher than 5.25V though.

Alex