I recommend that everyone build and test modules in stages.
Transformer wired up and tested.
Transformer + rectifier wired up and tested
Transformer + rectifier + smoothing wired up and tested.
All done via a Mains Bulb Tester
Second AndrewT's recommendation, and be sure to let the caps bleed down before connecting the amp.
I am about to build FW F6 and Aleph J amps, will run them in EU with 230V. I have a couple of questions regarding the PSU v3.
1. Is there a schematic for the v3 PSU for a stereo setup? I have been able to find what I think is a v3 mono (2012) and a previous version of the PSU in stereo (2005)?
2. Do I buy a 120V toroidal transformer and wire it differently (as above)? Or do I buy a 230V transformer which outputs 2 x 18V? Something like follows:
3. What are the components marked 'TH' which looks like a resistor with a diagonal arrow through them?
Thanks!
1. Is there a schematic for the v3 PSU for a stereo setup? I have been able to find what I think is a v3 mono (2012) and a previous version of the PSU in stereo (2005)?
2. Do I buy a 120V toroidal transformer and wire it differently (as above)? Or do I buy a 230V transformer which outputs 2 x 18V? Something like follows:
TTSAS0400 - SUPREME AUDIO grade transformer TSAS400VA - voltage to 50V - Shop Toroidy.pl
Nominal power 400VA
Input voltage 230V
Output voltage: 2 X 18 V
Nominal power 400VA
Input voltage 230V
Output voltage: 2 X 18 V
3. What are the components marked 'TH' which looks like a resistor with a diagonal arrow through them?
Thanks!
You can run a 120V transformer, and I believe you just wire the primaries in series instead of parallel. Doesn't matter which direction you go, I suppose.
The resistor with the arrow through it is the symbol of a thermistor. Actually a variable resistor, and I'm assuming the "TH" is for thermistor.
http://www.diyaudio.com/forums/imag...mentation/P-PSU-1V30/P-PSU-1V30-schematic.pdf
The resistor with the arrow through it is the symbol of a thermistor. Actually a variable resistor, and I'm assuming the "TH" is for thermistor.
http://www.diyaudio.com/forums/imag...mentation/P-PSU-1V30/P-PSU-1V30-schematic.pdf
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The PSUv3 board can be used for stereo or mono, the PSU doesn't change.
Have you seen the build guide? http://www.diyaudio.com/forums/powe...circuit-board-v3-illustrated-build-guide.html
You can use either a transformer with dual 120V primary and wire it appropriately as shown in the schematics, or use the Toroidy with the single 230V primary, and wire it just like the 230V diagram, except place the Thermistor after the fuse before the primary, as there is no place to connect it between the windings.
By all accounts, Toroidy makes excellent transformer. I would love to use one in my project.
CL-60 Thermistor
Thanks a lot guys. What would be the preferred option for use in 230V countries? Dual 120V primaries?
Dual 120V primaries will give you 230/240 x nominal secondary voltage.
230V primary will give you full secondary voltage.
Assuming that the wall power is a full 230V.
Regardless, you will lose a bigger fraction of the secondary voltage to dual primaries vs 230 primary....
230V primary will give you full secondary voltage.
Assuming that the wall power is a full 230V.
Regardless, you will lose a bigger fraction of the secondary voltage to dual primaries vs 230 primary....
That is true, but for purposes of completing his amplifier, the best choice is the transformer that is most easily obtainable. 🙂
Seems like 230V primary transformers are easiest to find here in EU, I will go for these.
6L6, your illustrated guides absolutely rock!
6L6, your illustrated guides absolutely rock!
EU uses 220/240Vac commonly referred to as 230Vac
Buy a transformer for THIS supply voltage.
It can be a single primary 230Vac, or a dual primary 115+115Vac
Both will work in the EU.
But Build and use a Mains Bulb Tester.
Note in the PASS sch that each 115Vac primary has a CL60 as a soft start circuit.
When you series connect two 115Vac primaries or use a single 230Vac primary you NEED two CL60 in series to match the soft start effect designed in by PASS.
Personally I prefer a higher cold resistance than what a pair of CL60 can give, but that is just me.
I also recommend that you arrange for a delayed relay bypass to take the CL60 out of circuit after the soft start is complete, i.e. after 100ms to 300ms.
Buy a transformer for THIS supply voltage.
It can be a single primary 230Vac, or a dual primary 115+115Vac
Both will work in the EU.
But Build and use a Mains Bulb Tester.
Note in the PASS sch that each 115Vac primary has a CL60 as a soft start circuit.
When you series connect two 115Vac primaries or use a single 230Vac primary you NEED two CL60 in series to match the soft start effect designed in by PASS.
Personally I prefer a higher cold resistance than what a pair of CL60 can give, but that is just me.
I also recommend that you arrange for a delayed relay bypass to take the CL60 out of circuit after the soft start is complete, i.e. after 100ms to 300ms.
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If resistor and led is used then there is no need for 2.2k bleed resistor as shown in Firstwatt power supply, or am I overlooking something?
Why faster?
The amp pulls the PSU down to near zero volts and the Led pulls it a little bit farther to ~1.8Vdc
What advantage do you see in going faster?
If the amp fails and stops pulling bias current then the LED alone will pull the PSU down fairly slowly. When you take the lid off you will see the LED glowing, telling you to be careful.
Decide if you want to stick a screw driver in there while the LED is glowing.
The amp pulls the PSU down to near zero volts and the Led pulls it a little bit farther to ~1.8Vdc
What advantage do you see in going faster?
If the amp fails and stops pulling bias current then the LED alone will pull the PSU down fairly slowly. When you take the lid off you will see the LED glowing, telling you to be careful.
Decide if you want to stick a screw driver in there while the LED is glowing.
Hello everyone. I am about to start on an Aleph J build and I purchased parts based upon the BOM that is listed on the excellent build guide on this site. I now have all the parts required, but when ordering I purchased four 33000uf capacitors based upon the older power supply board shown in the build guide. I have an Antek AN-5218 with 500VA and 2X 18v. The capacitors are four Cornell Dubilier 380LX at 33000uf and 50v. There is enough room on this board for eight of these capacitors. Is it a good idea to buy 4 more of these same capacitors and fill the available space on the board? In addition, I have on hand two of each of the following;
Mallory 62000uf 40 volts
Nichicon VR(M) 4700uf 63 volts
Elna for audio 6800uf 75 volts
Paradigm labeled 5600uf 50 volts
and four Shizuki 75uf 575 volt film capacitors
Is there any point in using any of these ones? I'm especially curious if the film caps would add anything. Also if I do use dissimilar capacitors, should they be arranged on the boarx in any particular order? My obsessive compulsive nature makes it difficult to leave all those empty spots on the board! Any advice that you all might provide would be much appreciated. Thanks in advance!
Mallory 62000uf 40 volts
Nichicon VR(M) 4700uf 63 volts
Elna for audio 6800uf 75 volts
Paradigm labeled 5600uf 50 volts
and four Shizuki 75uf 575 volt film capacitors
Is there any point in using any of these ones? I'm especially curious if the film caps would add anything. Also if I do use dissimilar capacitors, should they be arranged on the boarx in any particular order? My obsessive compulsive nature makes it difficult to leave all those empty spots on the board! Any advice that you all might provide would be much appreciated. Thanks in advance!
Are you planning an rCCCCC PSU, or rCRCCC, or rCCRCC
It makes a difference to what you use where.
It makes a difference to what you use where.
Can you elaborate? Google tells me that you seem to be the only person using this terminology 🙂.