Whatfor do i need a LAB PSU ?

[julian1]

This is Dave's review of the E3610A. They can be picked up on Ebay around $100, (although postage is an issue is you have to source it from overseas).



The advantages are simple, linear, no fan noise, top-brand, schematics are available. Disadvantages - you need two if doing dual rail. Definitely don't spend $400 on a power supply if you don't have a scope yet.

[bitseeker]

Disadvantages - you need two if doing dual rail. Definitely don't spend $400 on a power supply if you don't have a scope yet.

Note that the E3620A has two outputs and the E3630A has three (although the third is negative-only relative to common).

[julian1]

the E3620A has two outputs

Do those have current limiting? - it's a bit hard to tell the front-panel. They also command a higher-price - which means they compete against the features of more modern models (tracking, programmable etc).

[The Soulman]

i,m busy with audio

What are you doing with audio? dac, active filters, amplifiers?
solid state, tubes?
And more importantly, what do you want to learn from it?
I was like you 25 years ago.. 

[bitseeker]

the E3620A has two outputs

Do those have current limiting? - it's a bit hard to tell the front-panel. They also command a higher-price - which means they compete against the features of more modern models (tracking, programmable etc).

Unfortunately, they do not have adjustable current limiting, just short-circuit protection. Same story on the E3630A. However, they cost less than buying two (or three) single-channel models. They were HPs budget line, so not as much power or features as, say, the E3631A (triple-channel) or E364xA (dual channel) models.

[FlyingHacker]

I see no point in a "lab" supply without an adjustable current limit. You might as well use wall warts or batteries at that point.

[CraigHB]

That's pretty much the whole point of using a lab supply, ammeter and adjustable current limits.  I use the ammeter all the time and often rely on the set current limit.  Otherwise you could just use any ol' power supply.

[JanJansen]

What sorts of currents do you need your power supply to deliver?

Not much, not more then 1A maybe a half, that Peaktech PSU is overkill already.

Spend 1000 euros you can get Rigol DS1054z oscilloscope, Rigol DP832 bench power supply, and UNI-T UT61E multimeter from eBay. I think they are good enough to a beginner.

Noisey X 2, i rather have that €800 Hameg/R&S scope without noise.

You need 3 of these for audio (totally $2700). 2 for bipolar 15V/18V for OPAMP, and one for +12V or +5V for logic.
Make sure your bench top is free from any RFID equipment before using any Keysight gears .

Yeah, only i use single supply audio, the final build is powered from a wall adapter, i dont trust 220volt, i always find out the hard way.
Huh, RFID in Keysight gear ?, i,m not buying that brand or a rebadged brand, they are crazy, what is the use for that ?

What are you doing with audio? dac, active filters, amplifiers?
solid state, tubes?
And more importantly, what do you want to learn from it?
I was like you 25 years ago.. 

Hi, i make synthesizers instead of buying, not learning anything special, just to build more cheap synthesizers.
Right now at the moment, i re-make 25+ years old digital synthesizers like Yamaha DX7 & Casio CZ in 1 chip.
Did you have PIC chips with build in audio DAC + 128KB Program & 16,384 RAM Bytes 25 years ago ? 

I see no point in a "lab" supply without an adjustable current limit. You might as well use wall warts or batteries at that point.

That Peaktech has that, right ?, i going to buy that one not that noisey Rigol brand.
http://www.peaktech.de/productdetail/kategorie/schaltnetzteile/produkt/peaktech-6225-a.html

[FlyingHacker]

I see no point in a "lab" supply without an adjustable current limit. You might as well use wall warts or batteries at that point.

That Peaktech has that, right ?, i going to buy that one not that noisey Rigol brand.
http://www.peaktech.de/productdetail/kategorie/schaltnetzteile/produkt/peaktech-6225-a.html

I can't imagine the Peaktech is much less noisy. As others have pointed out a switchmode power supply is probably not a good idea for audio.

I might go with one of these:

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313.TR0.TRC0.H0.XLambda+LPT-7202-FM.TRS0&_nkw=Lambda+LPT-7202-FM&_sacat=0

[tautech]

I see no point in a "lab" supply without an adjustable current limit. You might as well use wall warts or batteries at that point.

That Peaktech has that, right ?, i going to buy that one not that noisey Rigol brand.
http://www.peaktech.de/productdetail/kategorie/schaltnetzteile/produkt/peaktech-6225-a.html

I can't imagine the Peaktech is much less noisy. As others have pointed out a switchmode power supply is probably not a good idea for audio.

That Peaktech ^^ is SMPS and somewhat noisy but quite OK for tinkering around with IF you add additional local smoothing capacitance to your projects.
As others have pointed out it's made by MCH and here's an older thread examining them in little detail:
https://www.eevblog.com/forum/testgear/cheap-variable-switching-power-supply/
 

[JanJansen]

Yes i always use big cap where the power goes in, then a 100ohm resistor and then again a cap.

I have the Peaktech 6225 A, i am very happy with it, glad i did not wait 60 years.
It is looking realy good, makes no noise at all, it dont get hot, and dont smell ( my old adapter alway get hot and smell ).

Ok, you can see its made in china :
The banana plugs dont go in totally, a half centimeter you see the metal.
When removing the plasic from the display, the display comes loose from the device ( it did not break and went back in place when the plasic was removed ).
One time when rotating the voltage encoder down, the voltage goes up instead of down.

Still for that money ( around 75 euros ), i am very happy, it measures how many mAh it takes, and very presice setting the voltage and max mAh.

[JanJansen]

I am not so happy no more with my Peaktech 6225 A :

[FlyingHacker]

Just get a older Lambda lab supply and be done with it. Linear, silent, bombproof, through hole, with schematics.

Lambda makes the power supplies for many of the big players. A lot of HPs and Agilent/Keysights, and others are Lambda supplies with some extra circuit board thrown in, and a much higher price. Those companies know if they want a good, reliable supply they start with a Lambda.

[rstofer]

Wow, i,m looking to the Rigol DP832 YouTube movie, it makes a lot of noise,
i,m busy with audio, so i dont want any Rigol gear, those scopes also makes noise.

Which kind of 'noise'.  If it is audible, well, that will be a function of load current on the DP832 but, yes, it is noisy enough to remind me that it is on.  For the DS1054Z, many people, myself included, have changed out the fan.  Details elsewhere.  I did it but I didn't really have to.  None of this stuff is anywhere near as noisy as one of my tower computers which already has sound absorbing padding.

If you're talking about electrical noise, I would expect to have to add both bulk and decoupling capacitance to the circuit anyway.  Long leads from the PSU to the project aren't really such a great idea.  Measuring noise with a scope just brings in the scope's own noise floor and that isn't anywhere near 0V.  If I use my handy dandy EEVBlog Brymen meter to measure electrical noise from the DP832, I get around 0.01 mV AC (unloaded).  My Fluke 189 gets a somewhat higher reading (like 0.15 mV AC) but, either way, well under 1 mV.

I have been messing around with this stuff for a very long time without a lab quality PSU.  It would be my last piece of equipment, not my first.  There are lots of ways to power circuits that don't involve spending a lot of money.  My order would be: DMM, Scope, Signal Generator then PSU.  Wall warts and USB work for me!

[james_s]

You don't *need* a lab PSU, it just makes life easier. I've always built my own, these days there are so many really cheap modules you can get that make it even easier. Surplus power bricks can be used as the source.

[JanJansen]

Its my first choise, i like it if it worked good, before i was blind, now i can see ( milliampere usage ), i dont wanto always use multimeter for that, besides i dont have the extra cables.
Also this thing is small, fits great in my house, it would be perfect, it makes no sound at all.

Now i am looking to a bit more expensive, 3 channel GW instek GPS-3303, since i was reading only good things about that brand.
The first thing i see on YouTube : GW INSTEK GPS-3303 CH1 malfunction


If i had the money i would invest 1000+ in a good 3 channel PSU, i hope the shop will replace mine with a updated working model or fix it, for 75 i cannot buy anything else, i need 75 and more on top of 1000 bwha.

[bingo600]

This is Dave's review of the E3610A. They can be picked up on Ebay around $100, (although postage is an issue is you have to source it from overseas).



The advantages are simple, linear, no fan noise, top-brand, schematics are available. Disadvantages - you need two if doing dual rail. Definitely don't spend $400 on a power supply if you don't have a scope yet.

Watch out getting especially the E3610A from overseas , Dave says in the video that they aren't switchable between 110v <--> 220v

/Bingo

[bghende]

If its in your budget, try to get a supply with an enable button. Nothing scarier than turning on the main power switch on a power supply connected to a load without knowing what the voltage and current limit settings are.

[james_s]

I always turn on the supply and then connect the load, I suppose an enable button would be more convenient though.

Power supplies are something I've always built myself. They make good beginner projects, you can start building simple ones and then move on to more advanced features.

[JanJansen]

The shop fixed the PSU, i removed the movies from youtube.

[VEGETA]

Lab supply is a must for me, but if you don't have money now maybe you can see this:



^ adjusted after  a stupid mistake!

[ProBang2]

Lab supply is a must for me, but if you don't have money now maybe you can see this:

https://www.youtube.com/edit?o=U&video_id=CJEQZV30sc8

Ahhh.... - nope. Nothing to see. Zero videos.   

[VEGETA]

OMG I am so stupid!

here is the link:

I copied the first one from my channel dashboard!!! 

gonna adjust it now;