Gary
Thanks,
The difference with the SQB plug is it has a spring/clip on the inside like shown in the image below, I searched for similar plugs but couldn't find any. One of the one's you have listed appears to have the clip but the data sheet doesn't confirm it. I have no idea how you are suppose to attach the ground to the plug shown in the image
Thanks,
The difference with the SQB plug is it has a spring/clip on the inside like shown in the image below, I searched for similar plugs but couldn't find any. One of the one's you have listed appears to have the clip but the data sheet doesn't confirm it. I have no idea how you are suppose to attach the ground to the plug shown in the image
Attachments
Hi all, I still get requests for PCBs but I have only some left for my own use. Although it was supposed to be a one time GB I don't like it that many can't build this PSU as it is an excellent performing device. I see it is also used for the Soekris DAM DAC, Raspberry Pi etc. which is good. You can set it at many voltages for many applications. It is a fault on my part to limit the design to Squeezebox Touch drives. I just can't support every possible application, that is why I put that limit on it. You are on your own or need to cooperate with the other builders for different applications with different voltages. I hope you can understand that.
Is a second run wished for ? It is only interesting to have a 100 pieces or more produced. Same quality, gold plated etc.
* The Rcore transformers are all sold and I can not get hold of any new ones anymore. Sorry. The Triad transformer is a nice replacement though with even lower dissipation of the reg. It lacks the very low stray field of the Rcore but since many will build the PSU in a separate case I guess this won't be a problem.
Is a second run wished for ? It is only interesting to have a 100 pieces or more produced. Same quality, gold plated etc.
* The Rcore transformers are all sold and I can not get hold of any new ones anymore. Sorry. The Triad transformer is a nice replacement though with even lower dissipation of the reg. It lacks the very low stray field of the Rcore but since many will build the PSU in a separate case I guess this won't be a problem.
Last edited:
Talking about strange coincidences ....I just got mail that my supplier has some Rcore transformers for me. Problem is that also some other voltage types are amongst them. He will check and have the 6V versions sent to me as long as I buy them all. He first joked that it will be 200 pieces 
He assumes they have 20 to 30 left which is an acceptable risk to me so I said yes.
I will keep you updated when they arrive and how many it will be.
He assumes they have 20 to 30 left which is an acceptable risk to me so I said yes.I will keep you updated when they arrive and how many it will be.
Last edited:
Talking about strange coincidences ....I just got mail that my supplier has some Rcore transformers for me. Problem is that also some other voltage types are amongst them. He will check and have the 6V versions sent to me as long as I buy them all. He first joked that it will be 200 pieces
I will keep you updated when they arrive and how many it will be.
Hello Jean-paul.
I can't pm you, could you check this?
2nd Group buy?
Jean-paul -
I'd buy 3-5 more boards, if only because I keep finding uses for a quiet, stiff, and adaptable low-voltage DC supply, and it looks like others may feel the same way also...
One of my (literally) breadboard supplies powering a Raspberry Pi 2 before being installed into a modified B&K amplifier:
I was given a stash of HDPE cutting boards which no longer met local food safety requirements, but which do make usefully stable, vibration-resistant, non-conductive platforms on which to prototype or build - are easily cut with a bandsaw, drill & tap well, and grip nylon screws tenaciously.
How good is this PSU?
Well, as I enter this msg, one PSU is powering a Raspberry Pi B, and a Centrance Dacport Slim, which are feeding a highly modified set of Fostex T50RP 'phones. This is a pretty stiff load, the Pi and it's USB WLAN adapter draw 750 -1.200ma, while the Dacport can easily draw 1000ma itself when driving 8 Ohm 'phones.
Embarrassingly enough, this combo may be the best digital music player in my house, it seems to be more effortless, have greater detail, a lower noise floor, and faster dynamics than the Burr-Brown PCM1794 DAC and modified Lehmann headphone amp I currently use.
Playing the '746' cut from Trio ELF's 746 album, the opening notes sound like neither a zither, nor an autoharp, but rather like what they actually are - upper register piano strings being played with brushes - lovely. Sven Faller's upright bass is woody, resonant, and full of resonances, Walter Lang's pedal work modulates correctly - which is crucial to express the unusual 7/4 time signature - like Brubeck's Take Five, it's what the piano <isn't> playing that sets the syncopation in motion.
Switching to an ASUS 5VDC, 2amp USB adapter, the same cut sounds quite different, much flatter, more compressed, and harsher - wife Katherine said about the snare drum brushwork: "They sound like dried peas rolling down a gutter..." which isn't very 'audiophile,' but seems appropriate.
We both disliked the sound when using the ASUS supply, but with your PSU in line - Katherine fell asleep about 7 minutes into the Trio ELF album - which, in itself, is very high praise indeed.
I can understand your reluctance to support a population of variant devices - it's hard enough to keep your original engineering goals from diffusing, let alone design for different voltages and loads.
But one must wonder if it wouldn't be worthwhile to make this project less proprietary, or perhaps just pitch it over the wall entirely and let the greater community assume the responsibility for support, modification and dissemination.
Yes, I realize that immediately the usual suspects and fellow suffers from ORD (Obsessive Repulsive Disease) will 'prove' that this PSU cannot possible drive XYZ device without sterilizing small animals for meters around, and that the cabal of unnamable gentlemen in far-off CarJackisStan will produce this device for a fraction of a sane price - but think of all the grim satisfaction you'll derive from watching the Egos and YanJing amplifiers go up in greasy black smoke.....
Cheers
Jim
Jean-paul -
I'd buy 3-5 more boards, if only because I keep finding uses for a quiet, stiff, and adaptable low-voltage DC supply, and it looks like others may feel the same way also...
One of my (literally) breadboard supplies powering a Raspberry Pi 2 before being installed into a modified B&K amplifier:
An externally hosted image should be here but it was not working when we last tested it.
I was given a stash of HDPE cutting boards which no longer met local food safety requirements, but which do make usefully stable, vibration-resistant, non-conductive platforms on which to prototype or build - are easily cut with a bandsaw, drill & tap well, and grip nylon screws tenaciously.
How good is this PSU?
Well, as I enter this msg, one PSU is powering a Raspberry Pi B, and a Centrance Dacport Slim, which are feeding a highly modified set of Fostex T50RP 'phones. This is a pretty stiff load, the Pi and it's USB WLAN adapter draw 750 -1.200ma, while the Dacport can easily draw 1000ma itself when driving 8 Ohm 'phones.
Embarrassingly enough, this combo may be the best digital music player in my house, it seems to be more effortless, have greater detail, a lower noise floor, and faster dynamics than the Burr-Brown PCM1794 DAC and modified Lehmann headphone amp I currently use.
Playing the '746' cut from Trio ELF's 746 album, the opening notes sound like neither a zither, nor an autoharp, but rather like what they actually are - upper register piano strings being played with brushes - lovely. Sven Faller's upright bass is woody, resonant, and full of resonances, Walter Lang's pedal work modulates correctly - which is crucial to express the unusual 7/4 time signature - like Brubeck's Take Five, it's what the piano <isn't> playing that sets the syncopation in motion.
Switching to an ASUS 5VDC, 2amp USB adapter, the same cut sounds quite different, much flatter, more compressed, and harsher - wife Katherine said about the snare drum brushwork: "They sound like dried peas rolling down a gutter..." which isn't very 'audiophile,' but seems appropriate.
We both disliked the sound when using the ASUS supply, but with your PSU in line - Katherine fell asleep about 7 minutes into the Trio ELF album - which, in itself, is very high praise indeed.
I can understand your reluctance to support a population of variant devices - it's hard enough to keep your original engineering goals from diffusing, let alone design for different voltages and loads.
But one must wonder if it wouldn't be worthwhile to make this project less proprietary, or perhaps just pitch it over the wall entirely and let the greater community assume the responsibility for support, modification and dissemination.
Yes, I realize that immediately the usual suspects and fellow suffers from ORD (Obsessive Repulsive Disease) will 'prove' that this PSU cannot possible drive XYZ device without sterilizing small animals for meters around, and that the cabal of unnamable gentlemen in far-off CarJackisStan will produce this device for a fraction of a sane price - but think of all the grim satisfaction you'll derive from watching the Egos and YanJing amplifiers go up in greasy black smoke.....
Cheers
Jim
JP ik krijg steeds dit bericht:
jean-paul has chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her.
If you are trying to send this message to multiple recipients, remove jean-paul from the recipient list and send the message again.
jean-paul has chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her.
If you are trying to send this message to multiple recipients, remove jean-paul from the recipient list and send the message again.
***SIGH***
I believe that I committed an unmentionable act upon an unsuspecting canine while attempting to post a picture in msg #268 - it should have looked like this:
Hopefully, this picture is viewable, and that infernal howling will cease.....
Cheers
Jim
I believe that I committed an unmentionable act upon an unsuspecting canine while attempting to post a picture in msg #268 - it should have looked like this:
An externally hosted image should be here but it was not working when we last tested it.
Hopefully, this picture is viewable, and that infernal howling will cease.....
Cheers
Jim
Arrrgh....
Just for giggles, please try opening the link in a new tab - for Windows & most Mozilla browsers try right-click - 'open in new tab' - Android browsers try long-press - ditto.
Thanks for the heads up - I really should just give up and get a Dropbox, or Photobucket account.
Cheers
Jim
That worked for Firefox.
Wow! You have it tightly packed. I like the cutting board idea. Not bad either that HDPE is available fairly cheaply from my local material supply house if I can't find any old cutting boards.
From your comments, I assume that you have no hum. I was curious about that because the Triad transformer should theoretically have more radiation than the R-core and I was worried about orientation relative to the board. I placed my Triad "end bells" parallel to the board to try to minimize the interaction, but you have yours perpendicular and very close to the board, apparently with no ill effects. Cool. It seems this PSU is insensitive to transformer radiation.
Jac
Further PSU follies
Jac -
One of the luxuries of prototyping on HDPE is that you tack components down with dabs of hot glue and pop them of with a metal 'spluger' until you find the layout which works best.
The PSU seems quite quiet, and fairly immune to radiated noise, although you can introduce noise via the input and LED leads.
In the final iteration of this build, I used foil-shielded ethernet cable for the transformer's output lead, a short length of 'Twinax' (shielded dual coaxial cable) for the AC input, and a foil-shielded USB cable for the DC output.
All of the shields were tied to a strip of 3mm solder wick which was hot-glued to the base to make a star ground connected to the center pin of the IEC connector. A new LED was flush-mounted to the board, since even twisting and ferrite-beading the LED leads didn't stop them from picking up RF from a class D amplifier in the same box.
The net result of this fussiness is that the DC output looks quite clean with about .5-1mv of uncorrelated AC noise under no load, rising to about 1.75mv of 60 Hz noise when driving the the Centrance Dacport quite briskly into an 8 ohm dummy load.
Since this is still something like 100dB down from the Dacport's 500mw @ 3v output I really can't find too much to whinge about...
Cheers
Jim
Jac -
One of the luxuries of prototyping on HDPE is that you tack components down with dabs of hot glue and pop them of with a metal 'spluger' until you find the layout which works best.
The PSU seems quite quiet, and fairly immune to radiated noise, although you can introduce noise via the input and LED leads.
In the final iteration of this build, I used foil-shielded ethernet cable for the transformer's output lead, a short length of 'Twinax' (shielded dual coaxial cable) for the AC input, and a foil-shielded USB cable for the DC output.
All of the shields were tied to a strip of 3mm solder wick which was hot-glued to the base to make a star ground connected to the center pin of the IEC connector. A new LED was flush-mounted to the board, since even twisting and ferrite-beading the LED leads didn't stop them from picking up RF from a class D amplifier in the same box.
The net result of this fussiness is that the DC output looks quite clean with about .5-1mv of uncorrelated AC noise under no load, rising to about 1.75mv of 60 Hz noise when driving the the Centrance Dacport quite briskly into an 8 ohm dummy load.
Since this is still something like 100dB down from the Dacport's 500mw @ 3v output I really can't find too much to whinge about...
Cheers
Jim
Last edited:
Hi Dr Jim, tight build but please use a metal case connected to PE for (RF) shielding and safety. Also 115V input connectors to the IEC inlet should be insulated versions to avoid accidental touching of those. PE MUST be connected to the metal case, GND should be left floating IMHO but check local regulations.
Regarding introducing noise via the input. Do you mean to the input of the PCB or to the transformers primaries ? My experience is that noise coming in from the mains connection is attenuated very adequate...but I use the Rcore transformer. In cases where RF transmitters are nearby it can be useful to use a ferrite bead core/ring to the primaries of the transformer. Put both L and N a few turns through the bead. This should be an insulated bead to avoid accidental shorts. What can't come in does not need to be filtered on the PCB
* I have some doubts about connecting the shielding of the DC output cable to PE.
Regarding introducing noise via the input. Do you mean to the input of the PCB or to the transformers primaries ? My experience is that noise coming in from the mains connection is attenuated very adequate...but I use the Rcore transformer. In cases where RF transmitters are nearby it can be useful to use a ferrite bead core/ring to the primaries of the transformer. Put both L and N a few turns through the bead. This should be an insulated bead to avoid accidental shorts. What can't come in does not need to be filtered on the PCB
* I have some doubts about connecting the shielding of the DC output cable to PE.
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.