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previous: GeetarJim I just got off the phone with my am... -- 12/5/2000 1:03 AM	View Thread

Re: Science Fair project

12/5/2000 3:17 AM
dpcoyle	Re: Science Fair project I assume your tech is talking about using a sine wave to feed your amp. That will give you information about the gain at the frequency of the sinewave. Another thing you can try is to feed a bunch of frequencies in at once and see what the tone controls do. A square wave consists of the fundamental and every odd order harmonic above it, all added together. You might try a 100Hz and a 1000hz square wave through the amp at a relatively low level, like a volt or two out, peak to peak, into a resistor of the same ohms as the amp is rated at, and for only a volt or two, a 25 watt should be fine. Do you have access to a frequency generator and an oscope at schoool or can your science teacher get you access to one, like at a local college or business? If you check the effect of the tone controls, you will see there is a definite change in the square wave, meaning a frequency area is beeing eaten or boosted. If you do this and want to know how to read the effect, I'll tell you, but I bet you can tell me after trying it. Dan

12/5/2000 3:17 AM

dpcoyle

Re: Science Fair project

I assume your tech is talking about using a sine wave to feed your amp. That will give you information about the gain at the frequency of the sinewave.

Another thing you can try is to feed a bunch of frequencies in at once and see what the tone controls do.

A square wave consists of the fundamental and every odd order harmonic above it, all added together.
You might try a 100Hz and a 1000hz square wave through the amp at a relatively low level, like a volt or two out, peak to peak, into a resistor of the same ohms as the amp is rated at, and for only a volt or two, a 25 watt should be fine. Do you have access to a frequency generator and an oscope at schoool or can your science teacher get you access to one, like at a local college or business?

If you check the effect of the tone controls, you will see there is a definite change in the square wave, meaning a frequency area is beeing eaten or boosted. If you do this and want to know how to read the effect, I'll tell you, but I bet you can tell me after trying it.

Dan

Replies:

GeetarJim My tech suggested using a radio set... -- 12/5/2000 3:47 AM