One wonders how many seconds 2sc5200/2sa1943 will put out 28.3 vac into 8 ohm speaker? (that's 100 W). Remember if using scope to multiply peak to peak sine wave voltage by .707
With MJ21193/21194 same price as those numbers here, I'm not going to buy any to find out. I picked up a blown amp that has boards for 2 pairs of those per channel plus transformers & fans for $20 + freight.
With MJ21193/21194 same price as those numbers here, I'm not going to buy any to find out. I picked up a blown amp that has boards for 2 pairs of those per channel plus transformers & fans for $20 + freight.
Frankly speaking i don't know about its class, yes i make my pcb with toner transfer method but not with fully ironing method. I use FR Thinner on toner transfer with light heat. This process finish in just 2-3 minutes. I used regular A4 paper. Toroidal transformer is idea but for one or two pairs. By the way where u got Toroidal transformer core, fresh or used. Now i am going to this amp with ten pairs.
Better. Has more capable outputs, if your can buy them. Two pairs output transistors would be a more secure 100W. PV-4 @ 120W 8ohm has two pairs MJ15024/15025.(The blown amp I paid $20 for) 15024/25 are much more SOA transistors than 2sa1943/2sc5200. .
D3 & D4, if installed on the output heat sink, can collapse the idle bias current as it heats up. TIP41/42 drivers are too slow to reproduce high frequencies IMHO. 741 op amp is archaic, Peavey used JRC4580.
Quote: By the way where u got Toroidal transformer core, fresh or used. Close quote.
I salvaged a whole 60 v toroid switcher power supply out of a Sanyo 50" (125 cm) LED TV on the curb on garbage day. Screen was broken. Fuse was blown, one 200 VDC filter cap obviously bulging. With the gain available cheap these days, don't know why you'd need +-46v rails. I'm getting 72W on single 60 v rail single pair OT.
D3 & D4, if installed on the output heat sink, can collapse the idle bias current as it heats up. TIP41/42 drivers are too slow to reproduce high frequencies IMHO. 741 op amp is archaic, Peavey used JRC4580.
Quote: By the way where u got Toroidal transformer core, fresh or used. Close quote.
I salvaged a whole 60 v toroid switcher power supply out of a Sanyo 50" (125 cm) LED TV on the curb on garbage day. Screen was broken. Fuse was blown, one 200 VDC filter cap obviously bulging. With the gain available cheap these days, don't know why you'd need +-46v rails. I'm getting 72W on single 60 v rail single pair OT.
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I know about mj15024/25 are more SOA Transistor then 2sa1943/2sc5200. Its not available in city. D3 & D4 not installed on output heat sink, if bias current collapse what u suggest.
About 741 op amp, i m used TL071. What u think about TL071.
This is my first board. My last other board is burned i don't know why, but i think I leave that board open or no input signal.
You can put D3-D4 on a solder terminal strip over the output transistors at the top of the heat sink as I did. See post 212 of Retro Amp 50W Single Supply picture 3 of the terminal strip. This will heat up and collapse the bias voltage some.
TIP071 is quieter than 741 slightly, but if you can get 5532 it is a lot quieter.
TIP41/42 driver transistors should have plenty of Ic and soa to drive 2 or 3 pairs of 2SA1943/2SC5200 output transistors for a reliable 100W amp. You'll need a 500 or 600 VA transformer though. Put little heat sinks on the driver transistors, as you see I have done in the link. For my 72W both sides at once amp (measured) I have a 72 V 6.5 A transformer regulated to 62 vdc.
TIP071 is quieter than 741 slightly, but if you can get 5532 it is a lot quieter.
TIP41/42 driver transistors should have plenty of Ic and soa to drive 2 or 3 pairs of 2SA1943/2SC5200 output transistors for a reliable 100W amp. You'll need a 500 or 600 VA transformer though. Put little heat sinks on the driver transistors, as you see I have done in the link. For my 72W both sides at once amp (measured) I have a 72 V 6.5 A transformer regulated to 62 vdc.
The board is definitely Do It Yourself.
If you try to get 24 VAC out of that (72W 8 ohms which I get on my single pair out AX6 through bass notes of a whole song) the output transistors may not last 100 msec. I have a heat sink AND a fan.
If you're a resource limited student or graduate (as I was once), you may be able to get a heat sink at a scrapyard, or from an employee who raids the dumpster at a food factory. Lots of VFD motor drives get blown up by the sanitation washdown in food factories. VFD's have heatsinks and 24 vdc fans. Blown PCAT power supplies have heat sinks and fans. Scrap LED televisions have the heat sinks, and usually many good FET transistors. Saw a LED tv on the curb on garbage day last week. As I say, I bought a whole blown 130 W/ch PA amp with heat sinks and fan for $20 via E-bay (plus $36 freight: buy from somebody nearby)
If you try to get 24 VAC out of that (72W 8 ohms which I get on my single pair out AX6 through bass notes of a whole song) the output transistors may not last 100 msec. I have a heat sink AND a fan.
If you're a resource limited student or graduate (as I was once), you may be able to get a heat sink at a scrapyard, or from an employee who raids the dumpster at a food factory. Lots of VFD motor drives get blown up by the sanitation washdown in food factories. VFD's have heatsinks and 24 vdc fans. Blown PCAT power supplies have heat sinks and fans. Scrap LED televisions have the heat sinks, and usually many good FET transistors. Saw a LED tv on the curb on garbage day last week. As I say, I bought a whole blown 130 W/ch PA amp with heat sinks and fan for $20 via E-bay (plus $36 freight: buy from somebody nearby)
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Congratulations on your build 
But **AT LEAST** bolt those transistors (with mica and grease) to a piece or junkyard surplus aluminum extrusion.
ANY piece of aluminum with at least one flat face to mount them is better than nothing.
But **AT LEAST** bolt those transistors (with mica and grease) to a piece or junkyard surplus aluminum extrusion.
ANY piece of aluminum with at least one flat face to mount them is better than nothing.
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Hello Gurpreet Turna
Where you get your heatsinks & Fan in India in my local area(Amravati, Maharashtra) is not available.
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You can got Heat sinks from local inverter manufacturer maybe fans too. I got these fans from my local area. You can got these fans form old computer power supply unit.
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