layout

[rtill]

Would anybody be willing to make a layout of the attached schematic? It's a pretty simple one. I hate to make excuses....but I just plain suck at making layouts.

***note....if somebody does create a layout, could you align the power (TIP) transistors to be attached to a heatsink***

Thanks!

http://europa.spaceports.com/~fishbake/amp/ca100.htm

[Greg Erskine]

hi rtill,

You might want to have a search for other threads on this amp. I've seen threads on this amp appear quite a few times over the years. From memory (would you trust it?) people have suggested it doesn't work very well.

regards

[Nordic]

Here, dunno if the diodes need to attach to the heatsink.

you can open it with the demo version of eagle.

[AndrewT]

choose a better schematic.

[jaycee]

Ah, that old chestnut. The only way you'll get 100W from that thing is with it's dying breath. The performance is dreadful.

There's a load of better amps out there with ready designed PCB's. Look at mikeb's symasym. It's not 100W but for a home amplifier, it has plenty of output power, and there's a PCB layout you can download and use.

[rtill]

Thank you so much for the layout!!!! I have been reading up on this circuit and I've come to the conclusion, for a newbie like myself, it's something to get my feet wet with. Can someone explain the "unstableness" to me....what is unstable? does it not keep a constant wattage....do the transistors get too hot.....am I gonna end up in the hospital if Iattempt this?

If anyone has any better ideas for a newbie to build a 100 watt, ideally 150 watt power amp that is easy to build, please post a schematic...

Thanks again!!!

[Nordic]

My suggestion for a newby is to build a lower power amp first....
Needs smaller heatsinks, transformers, and will be less money in the bin if you don't like it, make a mistake, or just plain, never finish it.

Look at the original DX amplifier for example... http://users.tpg.com.au/users/gerskine/dxamp/

Power is about 50W into 8 ohm, and 100W into 4, needs (read - is better without) no preamp.

It will teach you all the lessons you need to know to build more powerfull amps

Looking at your current schematic... as transistors or even resistors heat up, their resistance reduces... as their resistance reduces their current demands rise - 1v over 2R = 0.5A, 1v over 1R = 1A. So, if you have no way of combating this thermal slide, you will eventualy reach the point where the devices fail.

[AndrewT]

or go to ESP and pick one of his simpler projects.

[rtill]

Thanks for the recommendation...I will try the easy project you suggest.

although...
what amperage should be used on my current schem.? is 5 amps too much....the reason I ask is because I have a hammond 165P60 power supply http://www.hammondmfg.com/165.htm

I figured this would do the trick for this "easy" poweramp I originally intended on building.

[rtill]

another comment....

what kind of wattage is this design able to put out? Is it possible to push it to 100-150 watts?

http://www.kk-pcb.com/hiraga.html