benchtop PS w/ current limiter for A-J board test
Hi Folks,
I've completed my Aleph-J chassis and almost completed one of the boards.
I'd like to test the boards and trouble shoot before I build my PS and am thinking I may want an ecomonical benchtop PS with a current limit function.
Any brand/model, or other suggestions? I called Mouser but didn't really get anywhere in the conversation.
Thanks,
Mario
Hi Folks,
I've completed my Aleph-J chassis and almost completed one of the boards.
I'd like to test the boards and trouble shoot before I build my PS and am thinking I may want an ecomonical benchtop PS with a current limit function.
Any brand/model, or other suggestions? I called Mouser but didn't really get anywhere in the conversation.
Thanks,
Mario
invest in variac , proper Donut (higher secondary voltage , to be able to test higher powered stuff) , adequate C bank ....... and bulb tester
Thanks for the reply, ZM...already have a variac and will do on the others.
...a couple more newbie questions:
1) I've used my own 105c Nichicons for the boards' caps...correct uF and voltage per requirements. I've noticed, however, that they're much smaller than those in all the pics and don't occupy the full tracings on the board. I haven't mounted the boards yet and swapping into larger caps (like those on the bill or materials) would be easy enough....any reason to do so?
2) From the pics I notice a blue tie-band around the opposing jfet bodies....why is this and should I do the same?
cramming for burning amp,
Mario
...a couple more newbie questions:
1) I've used my own 105c Nichicons for the boards' caps...correct uF and voltage per requirements. I've noticed, however, that they're much smaller than those in all the pics and don't occupy the full tracings on the board. I haven't mounted the boards yet and swapping into larger caps (like those on the bill or materials) would be easy enough....any reason to do so?
2) From the pics I notice a blue tie-band around the opposing jfet bodies....why is this and should I do the same?
cramming for burning amp,
Mario
If you have caps of proper value, there's no reason to change them.
The ziptie is used to keep the jfet together, which helps a little with thermal tracking and stability. Use it or not, it will work well either way.
The ziptie is used to keep the jfet together, which helps a little with thermal tracking and stability. Use it or not, it will work well either way.
finally another block AlephJ is almost completed, both are biased to 400mV, dc offset is great. I have tested with 500mV bias and it's 52°C with air conditioner air blow directed to them, but it's just for testing.
since this is my first use on copper plate, just find out that my finger sweat react with copper and create ugly surface with so many finger print. air humidity also seems create darker colour on the surface after days. i have to brush and paint with clear coating, not to forget using gloves. it looks shiny now, eventhough square area around connector is uncoated.
the problem now is that i dont have 1 power cable for preamp and 1 channel still dont have 2K2 bleeder, the joy must wait for stereo listening.
since this is my first use on copper plate, just find out that my finger sweat react with copper and create ugly surface with so many finger print. air humidity also seems create darker colour on the surface after days. i have to brush and paint with clear coating, not to forget using gloves. it looks shiny now, eventhough square area around connector is uncoated.
the problem now is that i dont have 1 power cable for preamp and 1 channel still dont have 2K2 bleeder, the joy must wait for stereo listening.
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Hi Gadut
Haha you have build mono sit 2SK82 in the same Aleph J chassis.
Do you think finish all to supreme audiophile enjoyment and compare
audio performance and give us subjective description so very welcome 😀
Congratulations
I'm greedy boy 😀 my journey on digital source and dac is finished, maybe add ba3 preamp. so building several amplifier is the game. That SK82 is not finished yet, maybe next following weeks (i'm a slow builder). On my radar now : ZM BJ, F2 with TO3 irfp (got extra from teabag GB) or SS output, Papa vfet2 if i have enough luck on JA33.
another topic, i'm still reading to find out my speaker choice (no multiple build, only one choice) between Elsinore mk6 or FrugelHorn 10P or Fostex206 jericho horn.
soundhappy, I remember now, i thought i bought 2pair SK82 from you, in fact i got it from DIYspaceW 😀 it seems that he regret sold it to me, i found he open WTB for those vfet.
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Fantastic Gadut
Aleph J i have tested sound excellent i like it specialy with no inductive
wire wound source resistors connected without filters to full range speakers.
Like you i prepare diy some 193V Sony amplifier so curious about sound of two amplifiers side by side.
Yours have psu switch on the panel ?
Hope all is safe for precious vfet's.
Anyway master piece of diy , clean soldering, cabling,
high quality psu with classy copper oh yeah 🙂
nice impression on AlephJ, if source resistor is critical, it's worth to try those exotic duelund 0R5 / 5 Watt, CAST Carbon/Silver Resistor, $47 each 😀
i use this post as my reference for SIT L'amp : http://www.diyaudio.com/forums/pass-labs/201655-lamp-simple-sit-amp-88.html#post2967112
so it's worth to get best you can get on each part of it. I have got my choke 300mH 3A with M6 core, 4pcs elna cerafine 4700uF for output caps. ordered it 1year ago before currency xrate going crazy. I cant wait to compare both of them using fullrange driver, I'll test my rig on my friend's listening room with fostex206 and 3way floorstand with sba satori driver.
no switch for swapping AJ/SIT, it's bad idea. I only need to remove some psu cables. it takes a long time and multiple layout until i got this final one. As papa mentioned, power supply and chassis is the heaviest and most expensive parts on your amplifier, but UMS idea and Papa design that occupy same power supply is incredible
i use this post as my reference for SIT L'amp : http://www.diyaudio.com/forums/pass-labs/201655-lamp-simple-sit-amp-88.html#post2967112
so it's worth to get best you can get on each part of it. I have got my choke 300mH 3A with M6 core, 4pcs elna cerafine 4700uF for output caps. ordered it 1year ago before currency xrate going crazy. I cant wait to compare both of them using fullrange driver, I'll test my rig on my friend's listening room with fostex206 and 3way floorstand with sba satori driver.
no switch for swapping AJ/SIT, it's bad idea. I only need to remove some psu cables. it takes a long time and multiple layout until i got this final one. As papa mentioned, power supply and chassis is the heaviest and most expensive parts on your amplifier, but UMS idea and Papa design that occupy same power supply is incredible
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Wow nice photos thx !
Stay Gadut with yours and if you have curiosity first change only one 0.47R
this of output transistor and it is immediatly audible and after
you can change all source resistors mox Panasonic's if your taste.
This resonable cost Futaba MPC74 from Japan are very interesting
resistor in audio path but some match is necessary:
NOVA Elektronik - Metallband-Resistors - MPC - Fukushima Futaba
" Duelund " for
Greetings
😀
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I'm finding 3W metal oxide from Panasonic more than good enough (if they're good for Mithrandir ...... )
also - most modern WW squarethingy resistors are non-inductive .....
also - most modern WW squarethingy resistors are non-inductive .....
@ Diyers
After more research i see what MPC inside and surprise
not real wire wound , not real z-foil but minimalism of metal band.
This Japan brand is not produced in Fukushima area
so resistors don't glows in the dark sadly 🙂
After more research i see what MPC inside and surprise
not real wire wound , not real z-foil but minimalism of metal band.
This Japan brand is not produced in Fukushima area
so resistors don't glows in the dark sadly 🙂
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metal plate combo? metal plate composite?
anyway guys, in this page, all of your country flag colour are the same, just different position. well mine is minus one colour 😀
anyway guys, in this page, all of your country flag colour are the same, just different position. well mine is minus one colour 😀
Gadut, you cut the third color off in '49.
<= BadutMPS = MP Strip
MPC = MP Corrugated
Corrugated means wavy.
Meander would have been a better word, but Japanese to English is not always 1-on-1.
(as Francais vers l'Anglais, and di bahasa Indonesia ke Inggris)