faizanbrohi Posted July 17, 2006 Author Report Share Posted July 17, 2006 There is a big problem , i asked my friend today and he says , MJE15024 and MJE15025 is not available here :-[ , can you please suggest a replacement Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 17, 2006 Report Share Posted July 17, 2006 I don't know which transistors you can buy in your country. The output transistors in the schematic I posted have only one of them available at an American distributor. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 17, 2006 Author Report Share Posted July 17, 2006 I Found something else also , the part number in the schematic i posted is MJE15024 and MJE 15025 which is wrong , it should be MJ15024 and MJ15025 , however MJE15030 and MJE15031 are correct numbers Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 17, 2006 Author Report Share Posted July 17, 2006 i Have looked it up in farnell , i found the transistors by searching and selecting my country . My distributer is makkays , so i will be looking to contact makkays . However i glitch that makkays have these transistors on hand. if not they have to import . But still they cost around 5.5 pounds . which is approximatiley Rs 550 and it is really very expensice for a transisitor. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 19, 2006 Author Report Share Posted July 19, 2006 Well Thank God I got the Transistors at a low price , farnell is toooo expensive , i have bargained for Rs 1000 for 8 transistors , one transistors cost Rs 125 which is 1.25 pounds and 0.73 dollars i guess. so really low price. Well BEsides That i also have a 8 transisitor heatsink for only Rs 175 , which is 1.75 punds or 1 dollar approx.So I want to ask if this M250 can be used as a amplfier in the 500W inverter to increase power. and then use a power transformer afterwords.. Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 19, 2006 Report Share Posted July 19, 2006 I want to ask if this M250 can be used as a amplfier in the 500W inverter to increase power? Then use a power transformer afterwords..The 500W inverter won't work with an amplifier. The M250 amplifier can be used in a sine-wave inverter.If you use 8 car batteries in series to feed it positive and negative 48V, its output power will be only about 115W to about 200W and can be used with a 30VAC stepup transformer. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 so if different channels are used can it produce more power Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 IF there are common connections . what will happen parallel voltage is same only current divides , and we have a lot of current no problemooo one car battery is about 55A @ 12V , the one which i haveHere is an idea , what do you think Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 20, 2006 Report Share Posted July 20, 2006 so if different channels are used can it produce more powerAmplifier outputs should not be paralleled without adding series resistors. The resistors will waste power and cause poor voltage regulation.IF there are common connections . what will happen parallel voltage is same only current divides , and we have a lot of current no problemooo one car battery is about 55A @ 12V , the one which i haveEight 12V batteries in series can power many amplifiers. But then the charge in the batteries won't last very long. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 It is getting all in all expensive to build a sine wave inverter. Well Good news i will send some pictures of the heatsink i bought for the M250. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 HEre is a picture of heatsink Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 20, 2006 Report Share Posted July 20, 2006 You have a nice big heatsink, but you will be surprised at the amount of heat that your linear sine-wave inverter will make and a fan is probably also needed. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 Well Here is another Amplfier i found of 1.5 KW how is this Baby . this can drive upto 1.5KW , this is insanity , but wait just calculate how many batteries :o Godd Help me . No way , i neeed something like a ferroresonant transformer and a square wave inverter that's allll ;DFurther More this is the fans Pic , i am just asking do i include two fans on one heatsink or not ???. I am Eager to use one fan per heatsink . THe Fans are rated 12V @2.2W and 200mA approx . and no i am not using these heatsinks for the inverter , i am using them first for the M250 Amplfier , Stereo 500W x 2 , 250 Watt per channel . Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 20, 2006 Report Share Posted July 20, 2006 i am using them first for the M250 Amplfier , Stereo 500W x 2 , 250 Watt per channel .Are your speakers 4 ohms? The amplifier makes 250W into 4 ohms or 144W (maybe 150W) into 8 ohms per channel. I don't know if it can have 2 channels bridged to make 500W into 8 ohms. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 No i am actually making two complete units with common input right , amd i am using 4 ohms speakers . Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 20, 2006 Report Share Posted July 20, 2006 That is an awful lot of power. What is it for? Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 IT is to make Power Amplifier System with a CD Player and temprature display , 10 band VU meter and things like that.ok Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 20, 2006 Report Share Posted July 20, 2006 Be careful you don't go deaf.Many speakers have a sensitivity of 90dB/1W/1m. 250W in them produces a sound level of a whopping 114dB at a distance of 1m and 117dB if two speakers are playing. Much too loud. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 But the amplfiers that are in the market , especially Car Audio Amplfiers , are rated 1000W maximum value and 500W x 2 channel RMSIF i use one 250W for the Deck and the other one for the Car . i Will have to use a square wave inverter to produce 300W from a 12V car battery. and a square wave is easily converted to DC . Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 20, 2006 Report Share Posted July 20, 2006 The inverters in high power car amplifiers operate at about 65kHz and use Mosfets. Then the transformer and filter caps can be tiny.http://www.sound.westhost.com/project89.htm Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 20, 2006 Author Report Share Posted July 20, 2006 There is one problem , the output is only 35 and -35V , i neeed 55 and -55V Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 21, 2006 Report Share Posted July 21, 2006 The turns ratio of the transformer determines its output voltage. Then you will need heavier wire for everything and an extra pair of Mosfets for the higher power. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 21, 2006 Author Report Share Posted July 21, 2006 I can use MJ15024 in this configration , they are 250W power transistors , to increase power , beacuse MTP75N06 is not manufactured as well as MTP60N06 THis only Leave BUZ11 and IRF540 , which can be found . but if i use MJ15024 in parallel combination with a good heatsink will it workCan You tell be a more simpler method , how i can order a transformer with input ratings and output ratings . so it is easy. (ie input voltage , centre tapped , output input current) Quote Link to comment Share on other sites More sharing options...
audioguru Posted July 21, 2006 Report Share Posted July 21, 2006 The M250 amplifier is supposed to use four MJ15024 power transistors and four MJ15025 power transistors.A power transformer needs a primary AC voltage rating the same as your mains (240VAC, 230VAC, 120VAC) and for a stereo amplifier with 250W from each channel the secondary would be 80VAC centertapped, 8A which is also written as 40VAC-0V-40VAC, 8A. It will give positive and negative 54.5VDC at 5.7A. Quote Link to comment Share on other sites More sharing options...
faizanbrohi Posted July 21, 2006 Author Report Share Posted July 21, 2006 I think you are mistaken , i am talking about the Inverter That you send .. ;D Quote Link to comment Share on other sites More sharing options...
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