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4 transister Electra


 
6/13/2000 1:51 AM
Mike V
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4 transister Electra
I put together a 4 transister electra about 2 months ago, and couldnt get it to work at all. I put it aside after checking out all my connections. I decided I better figure it out before I start another effect.[ This was only my seconf effect I'v made] I'm getting a voltmeter and Ohm meter tommorow, so I can try to find my problem. Has any one built one, and is there anything I should look for. Thanks for any help. P.S. How common is it to burn up a transister,cap,diode, or resister? The Iron that I was using was 140 watts. I did use a clamp on heat sink though, and put a wet rag on the weld after.
 
6/13/2000 8:52 AM
aron
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Mike, Jack Orman mentioned a while back that the 4 transistor electra looked like it had problems and wouldn't bias or work correctly. Perhaps he was right. To avoid burning up a transistor, use transistor sockets.
 
 
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6/20/2000 3:18 AM
Larry
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Mike,  
 
I just put one of these together, and it sounds quite nice. I didn't have any trouble with the bias, but that certainly doesn't mean much. Might just be my sloppy construction "fixing" things for once!  
 
FWIW, I used "mps2222" transistors from Radio Shack. I selected then for gain in the 160-200 range, with the lowest at the input. (I was worried that too much hfe with four stages would get rough.)  
 
The pedal sounds thick and, well, fuzzy. The input control gets a nice range of sounds. Since I put it together in a plastic box, it also gets AM stations quite audibly! Gotta' do R.G.'s foil thing on that one.  
 
Larry
 
6/20/2000 2:15 PM
Jay Doyle
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Larry,  
 
I have to recommend Jack Orman's idea about making enclosures out of electrical junction boxes. If you go to Lowe's you can walk out with a 4 inch squre box of stainless steel that is very easy to drill through and runs you about $1.25. No, its not pretty, but I just want my circuit to work, not look good. Put some stick-on rubber feet and you are ready to go.  
 
FWIW,  
 
Jay Doyle
 
6/20/2000 5:37 PM
Eric H
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quote:
"4 inch squre box of stainless steel"
 
 
Dang, that IS cheap, SS is hard on bits, though ;)  
 
I'll second using the junction boxes --it's a great idea, and they look cool plain, or with bondo, elbow grease and paint you can make it fancy.  
 
-Eric
 
6/20/2000 5:41 PM
Jay Doyle
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Eric,  
 
I use one of those "Unibits" that R.G. recommends and it doesn't have any problems at all. Very strong.  
 
FWIW,  
 
Jay Doyle
 
6/20/2000 9:47 PM
Eric H
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I was joking, Jay --if those things are stainless steel i'll eat one :)  
 
-Eric
 
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