Guys, I thought it was about time I uploaded some photos of my progress 
It's a Nadja where I'm using external ADC, DAC, volume control and have spent effort (and money) on trying to get good results to both my ears and eyes.
Case is built to my spec by modu.
DAC is twisted pair buffalo.
ADC is beis.
Power supplies are JLM kraftwerk.
Transformers (2) from tortech.
Connectors from neutrik.
Motorised volume and VU driver circuits are nothing fancy.
VU meters look pretty.
LCD is the biggest I could find online.
Power supplies took some time as there's separate supplies for analog and digital devices; each of which has 5 (3+ve, 2-ve) rails for a total of 10 regulated rails. I divided those based on not polluting the most important supplies (ADC + DAC).
I'm really, really, really, really slow when I work but I think tonight marks the point when all my power supply, control and indication cabling is done. Now I just need to do signal cables which are a pain because they're all silver/teflon and hard to strip.
Can't wait until this thing is finished!
It's a Nadja where I'm using external ADC, DAC, volume control and have spent effort (and money) on trying to get good results to both my ears and eyes.
Case is built to my spec by modu.
DAC is twisted pair buffalo.
ADC is beis.
Power supplies are JLM kraftwerk.
Transformers (2) from tortech.
Connectors from neutrik.
Motorised volume and VU driver circuits are nothing fancy.
VU meters look pretty.
LCD is the biggest I could find online.
Power supplies took some time as there's separate supplies for analog and digital devices; each of which has 5 (3+ve, 2-ve) rails for a total of 10 regulated rails. I divided those based on not polluting the most important supplies (ADC + DAC).
I'm really, really, really, really slow when I work but I think tonight marks the point when all my power supply, control and indication cabling is done. Now I just need to do signal cables which are a pain because they're all silver/teflon and hard to strip.
Can't wait until this thing is finished!
Attachments
Hi Sean,
i'm afraid that rolling back software is not going to solve your issue. Pretty sure about it.
Now that you've installed the LCD back, you must set this in NUC again. Have you done that?
If you have, then it's probably the wiring. A short somewhere, could be? Check the wiring for shorts and continuity with your meter (beep).
Hope this helps
Nick
i'm afraid that rolling back software is not going to solve your issue. Pretty sure about it.
Now that you've installed the LCD back, you must set this in NUC again. Have you done that?
If you have, then it's probably the wiring. A short somewhere, could be? Check the wiring for shorts and continuity with your meter (beep).
Hope this helps
Nick
Question: The enclosed meanwell supplies like the RT-50B, are they "double insulated" already? Perhaps not the clearest question, but I´m putting one in a 1U aluminium chassis, and would ideally like the metal frame to be in contact with the aluminium to help conduct any heat. I have a smaller variant (5V) here, and it seems like the underside of the internal PCB is insulated with plastic.
Yes, changed the menus setting but no luck. I'll check the wiring again for issues.
Things like shorts or bad connections would not cause the strange graphics I showed photos of would they? You did suggest a "bad initialisation" before. What is the solution for such a thing normally?
Hard to say what bad connections would cause on the display - most likely a blank display.
When you intend to use a display in a system, it has to be initialized - i.e. the micro must send some commands initially. Which commands exactly, that depends on the display model. The pics of the OLED you've posted somehow reminded me of what I've seen when the initialization routine is not appropriate. But it could also be anything.
The solution for you is having your LCD working first, as it was before. Take your time and calmly inspect the wiring with a meter. Make sure you pull off the power chord before you touch any part of your build.
When you intend to use a display in a system, it has to be initialized - i.e. the micro must send some commands initially. Which commands exactly, that depends on the display model. The pics of the OLED you've posted somehow reminded me of what I've seen when the initialization routine is not appropriate. But it could also be anything.
The solution for you is having your LCD working first, as it was before. Take your time and calmly inspect the wiring with a meter. Make sure you pull off the power chord before you touch any part of your build.
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I am going to try the Najda. As far as the power supply I saw the posted options:
Any reason why I need to choose anything over the "RT-50B Mean Well?
Does it influence the sound quality? If so, than I'd rather get one that has the best sound quality (if the PS matters there)
Please let me know your recommendations.
Thank you,
Herman
Any reason why I need to choose anything over the "RT-50B Mean Well?
Does it influence the sound quality? If so, than I'd rather get one that has the best sound quality (if the PS matters there)
Please let me know your recommendations.
Thank you,
Herman
I don't like the Mean Well models too much because they have a high requirement in terms of minimal load. The Najda uses pretty little current; the Mean Well PSUs want to output more than 0.5 A on the 5V line in order to regulate. So if you're set to use this power supply, you should consider dummy loads - which is not elegant.
The TDK MTW line seems better suited.
The smaller and the larger models have no minimal load requirement at all.
The intermediary model (MTW30-51212) should output at least 0.5 A on the 5V line in order to have the +/- 12 V properly regulated. This is less of a concern because all the sensitive devices that are powered from these rails are buffered with an onboard regulator.
The PSU I use is the Skynet SNP-9021-1. This one has no minimal load requirement either.
The TDK MTW line seems better suited.
The smaller and the larger models have no minimal load requirement at all.
The intermediary model (MTW30-51212) should output at least 0.5 A on the 5V line in order to have the +/- 12 V properly regulated. This is less of a concern because all the sensitive devices that are powered from these rails are buffered with an onboard regulator.
The PSU I use is the Skynet SNP-9021-1. This one has no minimal load requirement either.
I did exactly that for a little while before getting a power supply that could handle low enough draw.
It was always warmish with the bigger supply and the resistors in...
SQ and PSU
Hi,
You can read our post Nr. 1808!
Don't forgrt that PSU is also a part of the signal
Hi,
You can read our post Nr. 1808!
Don't forgrt that PSU is also a part of the signal
[/PHP]
Is this enough output?
tdk MTW15-51212
TDK
TDK MTW 15-51212 is absolutely enough with regard to power delivery
Also, if linear (non-switching) is better for SQ, why is anyone still using the switching power supply?
Linear is more complicated to build and can be very expensive
What parts will I need to build a Najda linear power supply?
You will need at least 2 AC Transformers, then make rectification for 5, 12 -12 Volt, and last not least a good regulating shunt or series regulator for each supply.
Send me an e-mail if you need more details
Regards
Sigi
I use the JLM Audio Kraftwerk to supply my Nadja. It's a Linear PSU kit that generates 3 positive and 2 negative voltage rails from a single transformer. It's designed to be used with microphone pre-amps, so one of the positive rails has a voltage doubler/tripler on it (to get to +48v) which makes that rail useless for Nadja. Still though, you get the +12v, +5v and -12v needed for Nadja from a single 12-0-12 transformer. Or probably any transformer between about 6-0-6 and 18-0-18 (yay for regulators!)
It's cheaper to get a switching PSU and there may be cheaper linear supplies out there but I'm happy with the kraftwerk kit. JLM have another almost identical kit (can't remember name) with 5 rails that I've also used but went with the premium kraftwerk kit because.... well, why not?
I use the JLM Audio Kraftwerk to supply my Nadja. It's a Linear PSU kit that generates 3 positive and 2 negative voltage rails from a single transformer. It's designed to be used with microphone pre-amps, so one of the positive rails has a voltage doubler/tripler on it (to get to +48v) which makes that rail useless for Nadja. Still though, you get the +12v, +5v and -12v needed for Nadja from a single 12-0-12 transformer. Or probably any transformer between about 6-0-6 and 18-0-18 (yay for regulators!)
It's cheaper to get a switching PSU and there may be cheaper linear supplies out there but I'm happy with the kraftwerk kit. JLM have another almost identical kit (can't remember name) with 5 rails that I've also used but went with the premium kraftwerk kit because.... well, why not?
If you are interested you should read an article in volume 4 of John Walton about sonic performance of different regulators! Very interesting.
The Superregs
Hello! I'm going to order Nadja next week and I started to collect parts. Is this PSU will be OK?
MTW30-51212 TDK-Lambda | Mouser
I'm not sure about ripple and noise. They are 120-150mV. Not to much?
MTW30-51212 TDK-Lambda | Mouser
I'm not sure about ripple and noise. They are 120-150mV. Not to much?
The VFDs the polish supplier provides are do not fit in my milled front panel, so I ordered two Noritake CU16025-UW6J from a seller on eBay at 35 USD each. New?Japan?Noritake CU16025 UW6J VFD Display 2x16 Dot Character Display Module | eBay
These displays have the standard 75x31 hole positions, and they have been documented to work with one of the "backpacks" sold by Adafruit for the Arduino.
These displays have the standard 75x31 hole positions, and they have been documented to work with one of the "backpacks" sold by Adafruit for the Arduino.