cheap/chinese LPSU's - minefield?

[jabbr]

Ok here is this: https://www.ebay.com/itm/Assembled-S11-SUPER-linear-regulated-power-supply-board-LPS-PSU/111820643468?hash=item1a09079c8c:g:lNIAAOSw14xWQXTH

 

Best I can tell this is a specific vendor, and very upfront about what it is: indeed claims to be the sigma11 PCB design -- which would be copyrighted-- this is not a full supply. They state its "open source" etc, so ...??

 

The supplies that I have, are not this, don't resemble on the inside -- though the circuits may be similar. The discussion that I had with @look&listen was not about this product.

 

None of the links that I've posted appear to be direct sigma 11 copies nor do they claim to be.

[look&listen]

24 minutes ago, jabbr said:

Yeah and your particular vendor has serious QA issues ... 

So, mine work great. Maybe you lucky, or maybe not look hard enough?

 

Zerozone unit has exact PCB revision as old 65VA unit, but 1 big (filter)cap replace 9 old ones. Another 'variant'!

Other unit like 100VA unit, but grounded r-core shield & thin output wires (QA?)

 

26 minutes ago, jabbr said:

without having to repair each one before use ?

Maybe too much time spent in Troll thread make you nasty today?  

 

26 minutes ago, jabbr said:

they have 4 small transistors, 2 larger transistors and a bunch of caps...

4 TO-220 diodes (often Ultra Fast Recovery)

 

37 minutes ago, jabbr said:

Ok look, let's be very clear: I haven't seen one marketed as "Sigma 11", nor is there anything on ebay labeled "Sigma 11". can you provide a link?

Ok, sigh,

https://www.ebay.com/itm/Assembled-S11-SUPER-linear-regulated-power-supply-board-LPS-PSU/111820643468?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

 

https://www.ebay.com/itm/Low-Noise-S12-Super-regulated-linear-power-supply-board-5-30V-LPS-10000uF-/263610893782?oid=132048787951

No not "Sigma 11', but "S11" and variants

 

@jabbr, please sign off computer, walk away, get relaxing food, drink, & Sunday evening activities. Maybe listen to music for fun!  Wash toxic troll shit out of mind (for while) 

 

[barrows]

1 hour ago, look&listen said:

Recall one seller respect AMB enough to name source, others imply source with product naming (S11)

@jabbr,  The above quote suggests to me that these companies are marketing the product as "sigma11", am I reading this wrong?

 

Sonore designs and builds are own products.  John Swenson does our high speed PCB design and I do the power supply design (schematic/protos) and internal layout, and we use a sub contractor to layout the power supply boards.  We also use a small processor daughter board from a third party supplier, which mounts to the main board, as developing this ourselves, while possible, would add no benefit to our products, but would raise the price due to the development time involved.  We also use our own, proprietary OS (which has been copied without permission by various competitors), and have our own proprietary web based interface for configuring our products.  Our top level products (Signature Series) are hand built, one at a time, personally by me at Ice Station Zebra in Colorado.  The custom chassis for our Signature series products are designed by our VP, and manufactured in California.

[jabbr]

2 minutes ago, barrows said:

@jabbr,  The above quote suggests to me that these companies are marketing the product as "sigma11", I am reading this wrong?

 

There appears to be a board (not an assembled PSU) branded "ZeroZone" and listed by an ebay vendor which does claim to the "Sigma 11" ... fair enough

 

There are a whole bunch of other boards which don't claim to be "Sigma 11" but are discrete zener diode, MOSFET pass transistor based PSUs ... some of which I have, and these have R-core transformers ... again, the photos of the PCBs are not direct copies of the Sigma11 nor are they marketed as S11 or Sigma 11. 

 

I don't own a direct Sigma 11 copy, nor have ever posted a link to one. So I wouldn't say "companies" ?‍♂️

In some cases they give testing details and might claim 10 microvolt noise etc.

 

 

2 minutes ago, barrows said:

 

Sonore designs and builds are own products.  John Swenson does our high speed PCB design and I do the power supply design (schematic/protos) and internal layout, and we use a sub contractor to layout the power supply boards.  We also use a small processor daughter board from a third party supplier, which mounts to the main board, as developing this ourselves, while possible, would add no benefit to our products, but would raise the price due to the development time involved.  

...

 

Hey no problem ... I'm just suggesting that your circuit will resemble another board with iMX-6 processor -- yes, the processor SOM is an excellent approach -- and your "custom OS" is a custom Linux distribution (the kernel is of course open-source Linux). My point is that design patterns are shared in the industry and there are many circuit and software similarities. I'm a big fan of open source and also sensitive to people stealing IP, and the board labelled "S11" seems to do that. The others might just use a similar circuit/design pattern.

 

 

[look&listen]

31 minutes ago, barrows said:

The above quote suggests to me that these companies are marketing the product as "sigma11", I am reading this wrong?

Not mean to suggest that. Perhaps too much precision applied to 'unfettered entrepreneurship' to see clearly. 

 

1st- I see pictures, price, copy & keywords in eBay listings. Think "marketing" maybe too generous for simple sales situation? Not know of anymore then this extant, or necessary, other then little word-o-mouth (oops, guilty  ).

2nd- "S11" and such 'almost' names dance around issues of IP, never too specific. Change one resistor value & 'different' circuit! & so what? In China no law, no enforcement! Moot, but not sure Ti Kan claim or copyright efforts enough for court?

3rd- No rule of law, but rule of consumer? Only way to heart of business is money. But who will organize, publisize & participate in boycott?  (not me)

 

Would choose UTA JS-2 or PH SR-7 in millisecond if were affordable. But not sadly, so do best I can & share with similar others 

[the_doc735]

3 hours ago, barrows said:

No, I ride in the backcountry two to three days a week and this requires constant evaluation of the snowpack, weather, etc.  And of course in the event of an accident, I become the rescuer (or the victim, as the case may be) it is up to the individuals of the team to self rescue, waiting for outside rescue in avalanche burial = body recovery.

 

Sorry for the OT folks, back to your usual programming!

thanks for that, greatly appreciated, great picture! I used to help people before I was disabled myself. OK, back to topic (please).

[the_doc735]

four hours ago I posted this:

"So, if I get something like this and a well informed person on here says that some components are not that good! ...couldn't I simply replace the low quality items with things like: Mundorf caps, schottky diodes/rectifiers, metal film resistors etc?   (to upgrade the device to a better standard)? "

ON topic to my original question in my thread, but unfortunately @jabbr & @barrows decided to have a little argument, and as a consequence my question seems to be overlooked! I don't mind their discussion, quite interesting actually! But I wouldn't mind some help also please.

Thank you!

[the_doc735]

looking at this 4 way for my 4 wall wart replacement:

 

 

 

see top of picture!

 

This LPSU any good, even though it only has one tranny?

Expert suggestions greatly appreciated!

 

[jabbr]

3 minutes ago, the_doc735 said:

four hours ago I posted this:

"So, if I get something like this and a well informed person on here says that some components are not that good! ...couldn't I simply replace the low quality items with things like: Mundorf caps, schottky diodes/rectifiers, metal film resistors etc?   (to upgrade the device to a better standard)? "

ON topic to my original question in my thread, but unfortunately @jabbr & @barrows decided to have a little argument, and as a consequence my question seems to be overlooked! I don't mind their discussion, quite interesting actually! But I wouldn't mind some help also please.

Thank you!

 

First I stand corrected @barrows -- there are chinese PSUs being marketed as "sigma 11" (s11 is close enough in my book) and they advertise using the S11 pcb design so that's explicit and blatant -- I agree that those shouldn't be bought.

 

Second, in order to "upgrade" you need the schematic. What I like about these are that they include the case and r-core so you'd have to figure that out. I guess you could start replacing parts but better to just buy a board from amb.org and parts and build it from scratch, and that way you know what you are getting. You still need a case and transformer so you could start with the PSU and upgrade the entire board.

[the_doc735]

2 hours ago, jabbr said:

 

First I stand corrected @barrows -- there are chinese PSUs being marketed as "sigma 11" (s11 is close enough in my book) and they advertise using the S11 pcb design so that's explicit and blatant -- I agree that those shouldn't be bought.

 

Second, in order to "upgrade" you need the schematic. What I like about these are that they include the case and r-core so you'd have to figure that out. I guess you could start replacing parts but better to just buy a board from amb.org and parts and build it from scratch, and that way you know what you are getting. You still need a case and transformer so you could start with the PSU and upgrade the entire board.

thank you, couldn't I do the same with the 4 way unit I suggested? "this"   or is one tranny bad with 4 boards, for some reason?

 

[jabbr]

1 minute ago, the_doc735 said:

thank you, couldn't I do the same with the 4 way unit I suggested? "this"   or is one tranny bad with 4 boards, for some reason?

 

We’ve had a lot of confusion by discussing products we aren’t familiar with and I’m not going to comment on anything I haven’t used. I’ve posted links  — if you want something else, eBay and Alibaba are wide open to you.

[the_doc735]

2 minutes ago, jabbr said:

We’ve had a lot of confusion by discussing products we aren’t familiar with and I’m not going to comment on anything I haven’t used. I’ve posted links  — if you want something else, eBay and Alibaba are wide open to you.

I respect your decision. thanks for answering!

[mourip]

On 9/22/2018 at 12:28 PM, mourip said:

 

FYI. I own several MC200CM and when I was doing my research I found a TPLink datasheet that said it can also be powered by 5VDC. I never tried it but here is the link to the PDF.

 

I am using a 5v Teradak with voltage adjusted up to 6v to power a 5v LT3045 inside my Rednet D16 which had its SMPS removed. Works great.

 

I just put my MC200CM's back into my system. I am running the "clean" side from a 5V LPS and the other side from the standard SMPS brick. Works great on 5v.

[the_doc735]

5 hours ago, mourip said:

 

I just put my MC200CM's back into my system. I am running the "clean" side from a 5V LPS and the other side from the standard SMPS brick. Works great on 5v.

this is what I thought too!   ...until the experts pointed out that electric metal power cables don't understand humans one way street concept i.e everything progresses forward! Cables don't understand that idea! The interference from your wall warts can be blocked from going forward with a variety of methods inc. optic fiber cable setups. "BUT!" ~ the interference travels BACKWARDS into the AC field (in your house) and finds its way to your other hifi components mains inputs and inevitably corrupts those as well! So, the point behind the LPSU is not only to help the component it is directly attached to, BUT to help the rest of your system by not corrupting it with noise from your wall warts spewing switching noise BACK into your power network as well. Depends on how far you want to take the perfect system concept?

[Ralf11]

-140 dB is good enough for me

[Monge]

14 hours ago, mourip said:

 

I just put my MC200CM's back into my system. I am running the "clean" side from a 5V LPS and the other side from the standard SMPS brick. Works great on 5v.

Thanks for testing the MC200CM at 5V ? It’s apreciated here.

Cheers Monge

[mourip]

4 minutes ago, Monge said:

Thanks for testing the MC200CM at 5V ? It’s apreciated here.

Cheers Monge

No problem. I had removed the fiber for a while thinking that it did not matter and made for a jumble of wires but now I can see that it contributes to a blacker background and more fine detail. The straight ethernet cable to my router was probably the last grounded connection to the "dirty side. Everything else uses an LPS and goes to an unfiltered power strip that is connected to a large isolation transformer.

 

I also found that I cannot use a short ethernet cable from my server to my MC200 that has a metal covering on the connector. When I do use it I have an issue with the two media converters linking up. Probably a grounding issue when the cable end touches the metal plate on the back of my server. Using a short cable with a plastic end cover fixed that...

[the_doc735]

Just got this reply: "hello, max ripple is about 25uV, regards."

https://www.ebay.co.uk/itm/192527403829?ul_noapp=true

 

 

'THIS' could be good for my mobo power (CPU 12v ATX 12v/5v/3.3v)

 

 

...unless, that is, any knowledgeable person stops me BEFORE it's too late? i.e. any reason not to use this for my PLAYER PC?

 

For anyone interested: (not usually required)....

The −12 V supply was primarily used to provide the negative supply voltage for RS-232 ports and is also used by one pin on conventional PCI slots primarily to provide a reference voltage for some models of sound cards.

Formerly −5 V (     white wire), absent in modern power supplies; it was optional in ATX and ATX12V v1.2 and deleted since v1.3. A −5 V output was originally required because it was supplied on the ISA bus; it was removed in later versions of the ATX standard, as it became obsolete with the removal of the ISA bus expansion slots (the ISA bus itself is still found in any computer which is compatible with the old IBM PC specification.

PS_ON (power on) is a signal from the motherboard to the power supply. When the line is connected to ground (by the motherboard), the power supply turns on. It is internally pulled up to +5 V inside the power supply. A control signal that is pulled up to +5 V by the PSU and must be driven low to turn on the PSU.

PG - PWR_OK ("power good") is an output from the power supply that indicates that its output has stabilized and is ready for use. It remains low for a brief time (100–500 ms) after the PS_ON# signal is pulled low. A control signal that is low when other outputs have not yet reached, or are about to leave, correct voltages.

The +5 VSB supply is used to produce trickle power to provide the soft-power feature of ATX when a PC is turned off, as well as powering the real-time clock to conserve the charge of the CMOS battery. +5 VSB (+5 V standby) supplies power even when the rest of the supply wire lines are off. This can be used to power the circuitry that controls the power-on signal. 

 

[the_doc735]

Another possibility: (for mobo)

https://www.ebay.co.uk/itm/ZEROZONE-Assembled-Ultra-Low-Noise-linear-Power-supply-board-LPS-board-L158-25/131588996943?hash=item1ea350bf4f:g:WU0AAOSwLVZV3ZTL (x4)

+

https://www.ebay.co.uk/itm/220V-200W-R-Core-Transformer-for-Audio-Power-AMP-Amplifier-40V-40V-15V-15V/332071927187?hash=item4d51077d93:g:lhgAAOSwW6JYXplE (x1)

 

could this work? Looking for informed advice please?

[rickca]

3 hours ago, the_doc735 said:

max ripple is about 25uV

This sounds too good to be true.  How is this measured?  

[the_doc735]

1 hour ago, rickca said:

This sounds too good to be true.  How is this measured?  

I have know idea, please write and ask them as that wasn't explained to me.

Cheers!

[rickca]

42 minutes ago, the_doc735 said:

I have know idea, please write and ask them as that wasn't explained to me.

Cheers!

I'll leave  it to you to pursue if you think it's warranted.  I don't plan to buy these products.  Maybe some of the other contributors to this thread can comment on whether the design could reasonably be expected to deliver max ripple of 25uV.  Is my skepticism misguided?

[the_doc735]

6 minutes ago, rickca said:

I'll leave  it to you to pursue if you think it's warranted.  I don't plan to buy these products.  Maybe some of the other contributors to this thread can comment on whether the design could reasonably be expected to deliver max ripple of 25uV.

OK, I may try to dig out their test procedure to determine how they arrive at that figure. Thanks for the suggested question!

[sandyk]

17 minutes ago, rickca said:

I'll leave  it to you to pursue if you think it's warranted.  I don't plan to buy these products.  Maybe some of the other contributors to this thread can comment on whether the design could reasonably be expected to deliver max ripple of 25uV.

 It is achievable using this quoted technology :

Quote

Using precision voltage reference + high speed op amp + MOS output power Transistor

 

Whether it is or not is a different matter, and may be from the specifications quoted for a design based on this topology.

[rickca]

5 minutes ago, sandyk said:

Whether it is or not is a different matter, and may be from the specifications quoted for a design based on this topology.

OK that's why I'm asking if this is an actual measurement.  Thanks.