So I have been playing around with the 17vac 5a transformer that I am thinking of using for my project, as well as figuring out how to use my oscilloscope to try and see what sort of affect adding a cap (100mf 250v) across the rectified output has,using an NTE5322.
From what I am reading, to get a good look at the waveform, I need to load up the circuit, so I am using a plain table lamp with a 60w bulb measuring 18.9Ohms at the cord and that I connecting to the rectifier with just alligator clip jumpers. When I apply the load, the dc output drops from around 23.7 to 14.8.
Am I not looking at this scenario correctly, shouldn't I only be loading this thing up to around 1amp? This thing is supposedly rated to 5amp, I wouldn't think this would be enough load to cause that much of a voltage drop. Do have a cheap transformer or am I just letting my inexperience shine?
From what I am reading, to get a good look at the waveform, I need to load up the circuit, so I am using a plain table lamp with a 60w bulb measuring 18.9Ohms at the cord and that I connecting to the rectifier with just alligator clip jumpers. When I apply the load, the dc output drops from around 23.7 to 14.8.
Am I not looking at this scenario correctly, shouldn't I only be loading this thing up to around 1amp? This thing is supposedly rated to 5amp, I wouldn't think this would be enough load to cause that much of a voltage drop. Do have a cheap transformer or am I just letting my inexperience shine?
bulb hot resistance isn't same as cold resistance ; it's usually lower cold
however , you need to decide with what current you want to load circuit , for tests
you can predict much from real world with this little proggie : http://www.duncanamps.com/psud2/index.html
however , you need to decide with what current you want to load circuit , for tests
you can predict much from real world with this little proggie : http://www.duncanamps.com/psud2/index.html
I forgot about that. I'm such a dope.
I'm starting to think my scope might be broken as well. I'm 45 minutes into a "scopes for dopes" video that was recommended to me. I testing it against the internal .5v peak to peak square wave function, and it is far from a square. Instead of a square wave it looks like a 1/4 sine wave starts high(or low) then dropping off to ground on a curve. I'm looking up more info to see if there is anything else I can do to troubleshoot this thing before it heads to the trash.
I'm starting to think my scope might be broken as well. I'm 45 minutes into a "scopes for dopes" video that was recommended to me. I testing it against the internal .5v peak to peak square wave function, and it is far from a square. Instead of a square wave it looks like a 1/4 sine wave starts high(or low) then dropping off to ground on a curve. I'm looking up more info to see if there is anything else I can do to troubleshoot this thing before it heads to the trash.
Well,I finally finished assembly and testing. I gave up trying to make a power supply for now out of a 17v/5a transformer I had on hand. I was worried the 24vdc it was rectifying to was to high, and since my oscilloscope is questionable, and I don't have enough experience to just wing it on the power supply end of things. So I found a spare 19vdc 4.62a Dell laptop psu. Sounds good so far too my abused ears (a few too many Pantera concerts in my younger years!), I'm also pleasantly surprised at the output, especially with the 89db speakers I had on hand.
I'm tossing around the idea of making it into a media dock/charging station for my cell phone. There are several, basic docks on Amazon that I could reverse engineer right into the enclosure I'm going to build.
I'm tossing around the idea of making it into a media dock/charging station for my cell phone. There are several, basic docks on Amazon that I could reverse engineer right into the enclosure I'm going to build.
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I haven't touched my amp since last spring, everything in my life went on the back burner due to a family/health/marital issue (and resulting nervous breakdown). Now that my life seems to at least stabilized, I'm hoping to do a little more work my project.
I'm looking for suggestions on making a small set of bookshelf speakers that will compliment this amp. I'd like to try and get all of my components (except for enclosures) for under $100 if possible. I'm on the fence one whether or not I want to go with a single full range speaker for simplicity sake, but I'd much rather go with a multi-way setup if find an easy/cheap enough design?
I still don't have a final enclosure for my amp, my plan is to build it with the same materials to match whatever speakers I build.
I'm looking for suggestions on making a small set of bookshelf speakers that will compliment this amp. I'd like to try and get all of my components (except for enclosures) for under $100 if possible. I'm on the fence one whether or not I want to go with a single full range speaker for simplicity sake, but I'd much rather go with a multi-way setup if find an easy/cheap enough design?
I still don't have a final enclosure for my amp, my plan is to build it with the same materials to match whatever speakers I build.
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