cheap/chinese LPSU's - minefield?

[Monge]

8 minutes ago, mourip said:

 

I have been using a Teradak unit for several years. They even have an internal potentiometer that you can use to tweak the voltage a bit.

 

https://www.ebay.com/itm/TeraDak-DC-30W-TOUCH-DC9V-2A-Hi-Fi-Audio-Linear-Power-Supply-/130906580297?hash=item1e7aa3e549

@mourip Thanks ? So this one with LT3045 In series or parallel would be nice for TP link MC200CM version 2.23 I Think.

Cheers Monge

[barrows]

8 hours ago, the_doc735 said:

these are quite serious allegations to make! please don't put yourself at risk of a 'LIBEL' court case from china! Do you have any proof/evidence to back up your case? OR, do you expect people to believe your word alone? take care.

As to the use of counterfeit parts in China I have direct experience of it, it is commonplace and well known in the industry.  As i did not point out any specific product, there is no risk to me.

As to the use unauthorized use of AMB labs' intellectual property see this quote from their website:

 

• "There are "σ22" clone boards being offered for sale on ebay and elsewhere. They are inferior in quality, made without permission and a violation of the terms set forth on this website. AMB urges not to patronize those unscrupulous vendors."

I would recommend going to the AMB labs website, they offer some very good power supply designs for DIY with full instructions and they sell PCBs for them, and they also provide info for builders who can build their designs for you, but if you have some free time, learning to DIY is not that difficult for projects like these, and with their excellent instructions.

 

https://www.amb.org/audio/

 

They do not license their designs to Chinese vendors, so anything using a sigma11 circuit would be unauthorized.

 

[jabbr]

11 hours ago, the_doc735 said:

Something not right here! Can either of you clarify this conumdrum please? Many thanks!

I have built, and I own a number of power supplies — the ones I buy rather than build are generally to replace cheap wall warts in noncritucal situations and when I know the supply is being used as a preregulator. Teddy Pardo is a name brand vendor whose supplies are reasonable and which compare well in the Linear Audio testing. 

 

Current mirror/zener diode regulators are a common configuration —the Salas Reflektor-D uses in shunt config and the Sigma 11 uses with MOSFET pass — I don’t know the actual IP status around this basic circuit and would  suspect that if there is a patent that it’s expired, in any case it’s a well known design pattern. The sigma 11 is reportedly “open source” on the amb.org website — looks like a good design. Did Amb get its ideas from DIYAudio?

 

I do do love the Salas Shunt for analog and Reflektor-D for digital and if anyone wants to build, the boards/kits are available through DIYAudio.com 

 

In any case life is short and sometimes easier to pick up a cheap LPSU to replace a wall wart. I don’t spend any anxiety worrying about stuff that is upstream of my fiberoptic isolation network.

[Abtr]

On ‎9‎/‎20‎/‎2018 at 4:56 AM, the_doc735 said:

...did a quick search for this before posting and can't find a topic with this title, so..........

thinking of purchasing el cheapo LPSU's, one of the main outlets being ebay for example.

Does anyone have any advice in this minefield of devices as to what to definitely avoid at all costs and which are a much better bet, i.e. route out the cowboys and point out the good ones amongst the bunch?

e.g. wolf, I.AM.D, Breeze, ZeroZone, Weiliang, Studer, Jays, etc.

 

https://www.ebay.co.uk/itm/15W-AC-output-linear-power-supply-7V-18V-audio-amp-decoding-LP-phono-ULN-PSU/272263526102?hash=item3f642bb6d6:m:mBQKcZ_53QN89W2PI4EM8fw
https://www.ebay.co.uk/itm/STUDER900-15W-Regulated-PSU-DC-Linear-power-supply-5V-6V-7V-9V-12V-15V-18V-24V/142483146873?hash=item212ca84879:g:rZsAAOSwB3tZm~Vo
https://www.ebay.co.uk/itm/15W-Ultra-Low-Noise-Linear-Power-Supply-HIFI-DC-Regulated-PSU-5V-24V-Selection/272255800477?hash=item3f63b5d49d:g:KuwAAOSwhQhYzEkt
https://www.ebay.co.uk/itm/25VA-Ultra-Low-Noise-linear-power-supply-output-DC-5V-3A-upgrade-Raspberry-pi-3/142731699776?hash=item213b78e640:g:so0AAOSwL3JatLmm
https://www.ebay.co.uk/itm/Finished-HIFI-linear-power-supply-dc5v-dc12v-USB-Port-Ultra-Low-Noise-HIFI-PSU/273134084159?hash=item3f980f603f:g:HHMAAOSwB1JavYt~
https://www.ebay.co.uk/itm/Finished-15W-DC5V-USB-Double-Output-HiFi-Linear-Power-Supply-TALEMA-Transformers/273128977395?hash=item3f97c173f3:g:0SAAAOSwQq1bdM-9
https://www.ebay.co.uk/itm/25W-HIFI-Ultra-Low-Noise-Linear-Power-Supply-DC-Regulated-PSU-5V-24V-optional/272255794069?epid=840677436&hash=item3f63b5bb95:g:27cAAOSwintXR59W
https://www.ebay.co.uk/itm/Standard-Edition-25W-Ultra-low-noise-linear-Power-supply-DC15V-1-15A-HIFI-LPS/122629640292?hash=item1c8d4bd064:g:reEAAOSwTiRZgp~O
https://www.ebay.co.uk/itm/ZEROZONE-50VA-5V-5A-Ultra-Low-Noise-Audiophile-Hi-Fi-Linear-Power-Supply/123059070246?hash=item1ca6e46526:g:UlsAAOSw42paxR2i
https://www.ebay.co.uk/itm/50VA-HIFI-Ultra-low-Noise-Linear-Power-Supply-DC5V-9V-12V-15V-18V-24V-LPS-PSU/273372400529?hash=item3fa643cb91:g:XBgAAOSwIUZbZS1Q
https://www.ebay.co.uk/itm/Douk-Audio-15VA-Low-Noise-Linear-Power-Supply-5V-DC-5V-USB-Dual-Output-For-HiFi/273154877079?epid=24017941392&hash=item3f994ca697:g:V4YAAOSwBnZazwwt
https://www.ebay.co.uk/itm/SUPER3-5A-DC-Linear-Regulator-power-5V-7-5V-9V-12V-16V-24Vgreen-cube-transformer/253615196868?hash=item3b0ca4cac4:m:mZGXzFtGHO-4QKozeSz04qw
https://www.ebay.co.uk/itm/DC-Linear-power-supply-USB-DC5521-25W-3V3-5V-7-5V-9V-12V-16V-24V-3-5A-dual-out/273151072873?hash=item3f99129a69:g:Tp4AAOSw42JZKNGt
https://www.ebay.co.uk/itm/STUDER900-upgrade-talema-PSU-DC-Linear-power-supply-5V-6V-7V-9V-12V-15V-18V-24V/142484570344?hash=item212cbe00e8:g:MQsAAOSw7pNZnZp8
https://www.ebay.co.uk/itm/30W-Hifi-Ultra-low-noise-Linear-Power-supply-R-core-PSU-DC5V-9V-12V-15V-18V-24V/113191206845?hash=item1a5ab8bfbd:m:meW46J69Xpf9Px8M5roOcdQ
https://www.ebay.co.uk/itm/Nobsound-25W-USB-DC5-24V-Adjustable-Linear-Power-Supply-for-Audio-Digital-Device/283127539197?epid=16023134480&hash=item41ebb765fd:g:oioAAOSwtHZbhQrL
https://www.ebay.co.uk/itm/25W-TALEMA-Ultra-Low-Noise-LPS-DC-15V-1-5A-Linear-Power-Supply-psu-HIFI-AUDIO/131872401532?hash=item1eb435287c:g:-wEAAOSwRgJXgK5B
https://www.ebay.co.uk/itm/TALEMA-25W-24V-Linear-Power-supply-115V-or-230V-to-DC24V-L156-6/141751111753?hash=item2101065049:g:JvIAAOSwgQ9VpImk

https://www.ebay.co.uk/itm/NEW-25W-TALEMA-Ultra-Low-Noise-LPS-DC-5V-3-5A-Linear-Power-Supply-psu-HIFI-AUDIO/142049588319?hash=item2112d0b45f:g:arkAAOSwAPlXgK5G
https://www.ebay.co.uk/itm/120VA-HIFI-Ultra-low-noise-Linear-Power-supply-DC5V-9V-12V-15V-18V-24V-LPS-PSU/272753485878?hash=item3f815fe836:g:L94AAOSwB3pbcqVC
https://www.ebay.co.uk/itm/HiFi-PSU-TALEMA-25VA-Linear-Power-supply-DC5V-DC9V-DC12V-DC15V-PSU-for-optional/271905173892?hash=item3f4ecfb184:g:RMgAAOSwHUtazdlD

https://www.ebay.co.uk/itm/Finished-65VA-Ultra-Low-Noise-linear-Power-supply-5V-9V-12V-15V-18V-etc-L158/131585252822?hash=item1ea3179dd6:g:9CkAAOSwDNdVysUL
https://www.ebay.co.uk/itm/SUPER-3-5A-DC-Linear-Regulator-power-5V-7-5V-9V-12V-16V-24V-TALEMA-transformer/253615218117?hash=item3b0ca51dc5:m:maO4N_z9YhjSyHU7eHWUAhQ
https://www.ebay.co.uk/itm/50VA-HIFI-Ultra-low-noise-Linear-Power-supply-DC5V-9V-12V-15V-18V-24V-LPS-PSU/112445361966?hash=item1a2e440f2e:g:SXwAAOSwFJBZQ-HA
https://www.ebay.co.uk/itm/Finished-65VA-Ultra-Low-Noise-linear-Power-supply-5V-9V-12V-15V-18V-etc/121963519293?hash=item1c65979d3d:m:m3nxjeKDwfuACl3NOPZSAZQ

https://www.ebay.co.uk/itm/50VA-HIFI-Ultra-low-noise-Linear-Power-supply-DC5V-9V-12V-15V-18V-24V-LPS-PSU/192312745328?hash=item2cc6bb9d70:g:OZgAAOSwED5Zw5eT
https://www.ebay.co.uk/itm/Breeze-DU-U8-Audio-384khz-32B-Decoder-XMOS-U8-core-DAC-Asynchronous-USB-Coax/173074671690?hash=item284c0de84a:g:y3cAAOSwttVaTdR~
https://www.ebay.co.uk/itm/LKS-Linear-power-supply-DC-5V-USB-5V-for-DAC-with-25VA-Talema-transformer-PSU/272884127978?hash=item3f892958ea:g:1qgAAOSw6gRZ3rbf
https://www.ebay.co.uk/itm/XMOS-TALEMA-Linear-Power-Supply-25VA-5V-3-5A-USB-Port-Ultra-Low-Noise-HIFI-PSU/272331666971?hash=item3f683b761b:g:AnIAAOSwqfNXpKP5 
https://www.ebay.co.uk/itm/25VA-12V-2-0A-Ultra-Low-Noise-Linear-Power-Supply-TALEMA-upgrate-XMOS-Player/271834413657?hash=item3f4a97fa59:g:8ggAAOSw14xWI7Sn
https://www.ebay.co.uk/itm/New-150VA-DC-Regulated-High-Power-Linear-Power-Supply-DC-5V-24V-With-display/273245335179?hash=item3f9eb0ee8b:g:MdMAAOSwfshbDqbv
https://www.ebay.co.uk/itm/2017-HiFi-PSU-25VA-DC16V-1-5A-Linear-Power-Supply-for-Upgrade-AURALiC-Aries-Mini/272497900179?hash=item3f7223fa93:g:uTcAAOSwEzxYX7vS 
Swagman Lab. - https://www.ebay.co.uk/itm/Upgrade-Audiophile-Linear-Power-Supply-for-Musical-Fidelity-V-LINK-192-USB-B-DAC/281466137348?hash=item4188b06b04:g:jgYAAOSwQTVV8CeM

 

 

I use Zerozone units to power my DAC and active crossover. I think they are fine for the job, even though I use an additional LT3045-A voltage regulator for the crossover. 

[jabbr]

1 hour ago, barrows said:

 

https://www.amb.org/audio/

 

They do not license their designs to Chinese vendors, so anything using a sigma11 circuit would be unauthorized.

 

I didn’t ever hear of Sigma 11 or amb.org before @look&listen pointed out to me, so let me give my impressions:

 

a) use of “.org” is for nonprofits and amb.org advertises “open source” — I take open source very seriously and would like to see the exact open source license they are offering — otherwise false advertising!

b) is this a business?

c) do they own right that would enable them to license?

d) if the design was through “users” then who owns the rights? Does the owner of AMB Labs get rights to a design done through the community etc?

 

I wouldn’t be so sure here — in any case I quickly recognized a well known design pattern — the parts to make it are dirt cheap and hence little risk of counterfeit!  and I looked at the Sigma 11 circuit and immediately recognized the current mirror — knew it from Reflektor-D — but it’s in pass not shunt config, so looks good for higher current designs  

 

Bother to measure the “ultra el cheapo”? — which really are a variety of power supplies not one circuit? If not, have you “listened” to one? They sound as wonderful powering a low powered NAS or WiFi router as the music which flow through them!

[mourip]

3 hours ago, Monge said:

@mourip Thanks ? So this one with LT3045 In series or parallel would be nice for TP link MC200CM version 2.23 I Think.

Cheers Monge

 

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.

[the_doc735]

12 hours ago, sandyk said:

 

Neither of these supplies have a 3.3V output as you specified.

yes but they will: "custom-make other output voltage.

That's the 3 way model. (As per advert).

The other one (4 way) said in an email that they could also custom make voltage!

[the_doc735]

4 hours ago, barrows said:

As to the use of counterfeit parts in China I have direct experience of it, it is commonplace and well known in the industry.  As i did not point out any specific product, there is no risk to me.

As to the use unauthorized use of AMB labs' intellectual property see this quote from their website:

 

• "There are "σ22" clone boards being offered for sale on ebay and elsewhere. They are inferior in quality, made without permission and a violation of the terms set forth on this website. AMB urges not to patronize those unscrupulous vendors."

I would recommend going to the AMB labs website, they offer some very good power supply designs for DIY with full instructions and they sell PCBs for them, and they also provide info for builders who can build their designs for you, but if you have some free time, learning to DIY is not that difficult for projects like these, and with their excellent instructions.

 

https://www.amb.org/audio/

 

They do not license their designs to Chinese vendors, so anything using a sigma11 circuit would be unauthorized.

 

many thanks!

[the_doc735]

1 hour ago, 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.

but if you already have a LPSU why would you add a LT3045 to it?

[Ralf11]

13 hours ago, the_doc735 said:

these are quite serious allegations to make! please don't put yourself at risk of a 'LIBEL' court case from china! Do you have any proof/evidence to back up your case? OR, do you expect people to believe your word alone? take care.

 

if you work for a company in the business, then you are required to disclose it

[mourip]

2 hours ago, the_doc735 said:

but if you already have a LPSU why would you add a LT3045 to it?

 

In my case I was replacing an internal SMPS and wanted to have the regulation to remain local. Also there can be benefits to having serial regulators or a "pre-regulator".

[the_doc735]

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)? 

 

 

[barrows]

7 hours ago, jabbr said:

I do do love the Salas Shunt for analog and Reflektor-D for digital and if anyone wants to build, the boards/kits are available through DIYAudio.com 

While I have used Salas' shunt regulator designs quite often (and they are excellent) I would not really recommend them for things like a computer server, or a renderer, as these devices have a very wide range of current consumption, where they may require a very high initial current to boot up, and then the current use drops way down.  With a shunt you have ti set the CCS high enough to meet the boot up current demand, problem being that when the current use drops the heat level goes way up.  While it is possible to use them for this, it will generally require enormous heatsinks to keep things from releasing smoke.

IMO a better option for powering these types of devices is a linear-series style reg, like sigma 11, etc.

 

As to the meaning of "open source" my understanding is that for AMB designs, this means they are free to use for individuals, but not for commercial purposes.  Considering the effort put in by the designer in maintaining the website, designing and selling PCBs, and the very, very detailed instruction and support provided there, if it is not illegal to copy their designs, it is certainly very bad form and to be frowned upon.

 

Now I do not subscribe to the life approach "if I get away with it is OK", I know some people do that, but we should all be better humans than that.

[Ralf11]

3 minutes ago, barrows said:

... I do not subscribe to the life approach "if I get away with it is OK"...

 

 

?? your avatar shows a snowboard on your back, and you live in a high avalanche area

[jabbr]

5 minutes ago, barrows said:

As to the meaning of "open source" my understanding is that for AMB designs, this means they are free to use for individuals, but not for commercial purposes.  Considering the effort put in by the designer in maintaining the website, designing and selling PCBs, and the very, very detailed instruction and support provided there, if it is not illegal to copy their designs, it is certainly very bad form and to be frowned upon.

 

What evidence do you have that they copied the AMB design? Why are you saying that? I said that the designs sound similar but honestly do you consider a "current mirror, zener diode, MOSFET transistor pass" to be an AMB proprietary design? Do you think that AMB invented this design pattern? 

Really?

 

[barrows]

4 minutes ago, Ralf11 said:

 

 

?? your avatar shows a snowboard on your back, and you live in a high avalanche area

Sounds off topic, but yes, i am an avid backcountry snowboarder and I deal with avalanche risk evaluation and avoidance on a regular basis.

[barrows]

3 minutes ago, jabbr said:

What evidence do you have that they copied the AMB design? Why are you saying that

Perhaps i am mistaken.  lookandlisten described the circuit as sigma11 in this thread, if it is not then that is another thing.

 

I am well aware of the Chinese tendency to revise engineer most of the designs which come out of China, everyone in the industry deals with this on a regular basis, so if it is a direct copy I am not surprised, but perhaps I misunderstood lookedlisten's post.

 

I have also seen the notifications at AMB labs' website warning of the clone PCBs available on eBay.

[jabbr]

8 minutes ago, barrows said:

Perhaps i am mistaken.  lookandlisten described the circuit as sigma11 in this thread, if it is not then that is another thing.

 

I am well aware of the Chinese tendency to revise engineer most of the designs which come out of China, everyone in the industry deals with this on a regular basis, so if it is a direct copy I am not surprised, but perhaps I misunderstood lookedlisten's post.

 

I have also seen the notifications at AMB labs' website warning of the clone PCBs available on eBay.

 

Right but consider this: https://patentimages.storage.googleapis.com/4a/5d/02/fb481b20f81835/US5955915.pdf

patent from 1999

(including figure 2 which is prior art)

[the_doc735]

36 minutes ago, barrows said:

Sounds off topic, but yes, i am an avid backcountry snowboarder and I deal with avalanche risk evaluation and avoidance on a regular basis.

well done, sounds like you are a rescuer?

[barrows]

23 minutes ago, the_doc735 said:

well done, sounds like you are a rescuer?

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!

[look&listen]

56 minutes ago, barrows said:

Perhaps i am mistaken.  lookandlisten described the circuit as sigma11 in this thread, if it is not then that is another thing.

Maybe I type mistake, but always try say "Sigma 11 variant LPSU"!

 

Research many things on eBay & see 5-6 different 'variants' from different listings & sellers. Some look similar to AMB board layout, but ad copy & pictures not sufficient to compare PCB layout, part values, or brands. Recall one seller respect AMB enough to name source, others imply source with product naming (S11). PCBs different then AMB layout show sigma11'ish features in capacities, parts layout & hints from text copy, but never circuit schematic for proof. Requirement to fix Vout at order time, also clue.

 

I not know if any 'variant' exact copy of AMB, (not care) but close enough, I think, for description.

Not know IP issue details, but agree with jabber, many unanswered questions.

 

PS. Must credit @Superdad CA comment somewhere first point me to Sigma 11  

[sandyk]

9 hours ago, barrows said:

As to the use of counterfeit parts in China I have direct experience of it, it is commonplace and well known in the industry.

 

Several members of a U.K. based forum who were constructing my Class A Preamplifier design were caught out by counterfeit Toshiba 2SC5171 transistors with very low HFE and a slightly different looking logo supplied by a major U.K. distributor, who to their credit quickly withdrew them from sale.

[barrows]

1 hour ago, jabbr said:

Right but consider this: https://patentimages.storage.googleapis.com/4a/5d/02/fb481b20f81835/US5955915.pdf

patent from 1999

(including figure 2 which is prior art)

I am just going to respect this statement printed at the AMB labs website:

 

"Copyright © Ti Kan, 
All rights reserved. Commercial use of this design is prohibited without prior permission."

 

I understand that similar (but not identical) circuits have existed for a long time, still, it would appear to me that marketing a commercial product as sigma11 is in direct violation of the above, at least in spirit if not legally.  The violation of that spirit alone is enough for me to accept that it is wrong.

[jabbr]

40 minutes ago, look&listen said:

Research many things on eBay & see 5-6 different 'variants' from different listings & sellers.

 

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

 

I've used this: https://www.ebay.com/itm/Finished-100VA-Ultra-Low-Noise-linear-Power-supply-ouptut-9v-12v-19v-24v-etc/221884083511?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

and the ZeroZone:

https://www.ebay.com/itm/ZEROZONE-100VA-100W-HIFI-Linear-Power-supply-DC-19V-TOP-LPS-for-amp-DAC-PC/321906781523?hash=item4af323ad53:g:bXQAAOSw~bFWM0c0

without having to repair each one before use ?

[jabbr]

8 minutes ago, barrows said:

I understand that similar (but not identical) circuits have existed for a long time, still, it would appear to me that marketing a commercial product as sigma11 is in direct violation of the above, at least in spirit if not legally.  The violation of that spirit alone is enough for me to accept that it is wrong.

 

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? Without a link you are spreading FUD.

 

Why are you persisting in this despite lack of evidence?, @look&listen clarified the situation "the boards look similar", yep they have 4 small transistors, 2 larger transistors and a bunch of caps... and heatsinks... c'mon man.

 

Who makes your boards? solid-run?