You MUST adjust the pots so that the output is near 0V before connecting the speakers!!! adjust VT3 first, then VT2 and VT1.
Yes we provide assembly kit. MJ15003 works excellent for both high and mid range frequency. this PSU is highly recommended:
Hi-End Power supply board with speaker protecting - Boards | Kits | Components | Modules | Tools
there's a newer version for this PSU recently, looks different.
200x150x50mm heatsink is suggested for each MJ15003
Yes we ship to India.
thank you siliconray
just ordered 2 boards, maybe in the future I will manage to do an A/B comparison with my Aleph Js
Hi
As stated in my last post,speakers not connected,input shorted.
No chance to measure or regulate anything,the bd130 blows instantly when power is applied ?
Faulty bd139 ? all 4 ?,I dont think so ! but then there is another post here #63,same problem ? Shorted bd139 !
It seems his worked with just a replacement.
Jan
The operator and how far he/she adjusts the volume control determines the sound output coming from the speakers.
A sensible operator does not overload the speaker, nor do they overload the amplifier.
The Maximum volume before these two overload conditions is determined by the speakers' abilities and the amplifier's abilities.
The amplifier transformer Vac rating determines the the voltage supplied to the amplifier and that determines the maximum output from the amplifier.
VA of itself does not determine maximum output voltage/power.
Thanks.
I'm still lost though. The PCB says "+-18V to +-25V" at the top, then at the right side of the PCB it says "+22" and "-22".
http://www.siliconray.com/media/cat...525d08d6e5fb8d27136e95/j/l/jlh-2005-pcb_1.jpg
So should I get a transformer that is from 9V+9V to 12.5V+12.5V, or should I get a transformer that is 22V+22V?
I noticed "speedless" posting above me was using 25V+25V, is that twice the maximum voltage specified? Is that why he fried four transistors?
I've ordered everything except for the transformer because it's so confusing and there's so many different kinds, they also have different Ampere output.
Everything in this article tells me I should select the R-Core type Products - Custom Magnetics, Inc.
I'm happy to get an R-Core 200W 24+24V from here if it doesn't make the transistors hot like hell so I need a cooling fan?
I'm still lost though. The PCB says "+-18V to +-25V" at the top, then at the right side of the PCB it says "+22" and "-22".
http://www.siliconray.com/media/cat...525d08d6e5fb8d27136e95/j/l/jlh-2005-pcb_1.jpg
So should I get a transformer that is from 9V+9V to 12.5V+12.5V, or should I get a transformer that is 22V+22V?
I noticed "speedless" posting above me was using 25V+25V, is that twice the maximum voltage specified? Is that why he fried four transistors?
I've ordered everything except for the transformer because it's so confusing and there's so many different kinds, they also have different Ampere output.
Everything in this article tells me I should select the R-Core type Products - Custom Magnetics, Inc.
I'm happy to get an R-Core 200W 24+24V from here if it doesn't make the transistors hot like hell so I need a cooling fan?
Does the PCB or the instructions tell you the DC voltage required to power the amplifier?
If the suggestion is that +-22Vdc is about right, then you need a 0-18, 0-18Vac dual secondary transformer.
If your level of understanding of these topics is as low as you are getting confused with transformer ratings then I suggest you ask advice BEFORE you connect things up.
I also suggest you build and USE a Mains Bulb Tester to stop you blowing up projects because you have wired them up incorrectly.
If the suggestion is that +-22Vdc is about right, then you need a 0-18, 0-18Vac dual secondary transformer.
If your level of understanding of these topics is as low as you are getting confused with transformer ratings then I suggest you ask advice BEFORE you connect things up.
I also suggest you build and USE a Mains Bulb Tester to stop you blowing up projects because you have wired them up incorrectly.
I realised I have an amplifier on the way with a 200W 23V output transformer.
I think I'll just take the transformer out of that one and use it for this project.
The Antek transformers Transformers - AnTek Products Corp... do look very nice and at least one user here has confirmed he using a 400VA 18V flawlessly.
I think I'll try the 500VA 20V from them later AN-5220 - 500VA 20V Transformer - AnTek Products Corp
The price is very good, the shipping is a little high but perfectly fine for a 5 KILO transformer.
He said the 400VA is "a little warm" earlier in this thread, so I assume 500VA will be fine, and 20V is also fine since the PCB says up to +-25V.
I think I'll just take the transformer out of that one and use it for this project.
The Antek transformers Transformers - AnTek Products Corp... do look very nice and at least one user here has confirmed he using a 400VA 18V flawlessly.
I think I'll try the 500VA 20V from them later AN-5220 - 500VA 20V Transformer - AnTek Products Corp
The price is very good, the shipping is a little high but perfectly fine for a 5 KILO transformer.
He said the 400VA is "a little warm" earlier in this thread, so I assume 500VA will be fine, and 20V is also fine since the PCB says up to +-25V.
He said the 400VA is "a little warm" earlier in this thread, so I assume 500VA will be fine, and 20V is also fine since the PCB says up to +-25V.[/QUOTE]
I'm not quite sure why anyone would want to use 500VA on this circuit.
120W would probably suffice, 160W about ideal and 200W overkill.
Output voltage 18-0-18 if rudimentary smoothing PSU or 22-0-22 if you intend to use regulated PSU.
I'm not quite sure why anyone would want to use 500VA on this circuit.
120W would probably suffice, 160W about ideal and 200W overkill.
Output voltage 18-0-18 if rudimentary smoothing PSU or 22-0-22 if you intend to use regulated PSU.
RE3209H is a nice choice. RE4315H is a better one if you need a better looking and more power.
who use 500VA? Maybe he was building a 8 way speaker...
I'm not quite sure why anyone would want to use 500VA on this circuit.
120W would probably suffice, 160W about ideal and 200W overkill.
Output voltage 18-0-18 if rudimentary smoothing PSU or 22-0-22 if you intend to use regulated PSU.[/QUOTE]
I'm not quite sure why anyone would want to use 500VA on this circuit.
120W would probably suffice, 160W about ideal and 200W overkill.
Output voltage 18-0-18 if rudimentary smoothing PSU or 22-0-22 if you intend to use regulated PSU.[/QUOTE]
Hi
Im kind of sad to post this.
My amps are now working perfect.
I chose to replace EVERY transistor! Didn't trust them (see att.).What a bore!
The pic. is one of the delivered "MJ15003",in undressed condition.
(No porn!,more like opening a poor grave)
Heres a link you should see to compare the "innerguts"
Counterfeit Transistors
Jan
Jane?
Im kind of sad to post this.
My amps are now working perfect.
I chose to replace EVERY transistor! Didn't trust them (see att.).What a bore!
The pic. is one of the delivered "MJ15003",in undressed condition.
(No porn!,more like opening a poor grave)
Heres a link you should see to compare the "innerguts"
Counterfeit Transistors
Jan
Jane?
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