I hope you guys can bear with me on this one. I'm very new to building circuits but I'm trying to learn. Here's what I'm looking at.
If anyone is familiar with a Chassis Ear, it's a piece of equipment used by auto techs to track down noises. It has 6 leads with alligator clips to attach to the component in question and the leads go to a box with a selector knob to select which channel to listen to and a set of headphones plug into it.
Here's my situation, I have one of these that I'm pretty sure the box went bad on it and I have long since gotten rid of it. (wish I hadn't) Now what I'm trying to do is build another one so I can use this tool again.
I recently bought a Radioshack electronics learning lab and found a way to amplify the signal using a 272 OP-Amp and then further amplify that using a 386 audio amplifier. I have substituted the alligator clips from my Chassis Ear with this circuit and it works great but I'm concerned about the current this setup will use seeing as how it will be powered by a single 9 volt battery.
From what I remember of the old box, I don't remember seeing any IC's so I was thinking it might have just used a couple transistors to amplifiy the signal. Even if I have to use an IC to amplify the signal I've read that I could substitute a small transformer for the 386 amp to cut back on current.
So what do you guys think? Am I on the right track with this or do I just sound like a complete idiot Any thought or opinions would be greatly appreciated.
If anyone is familiar with a Chassis Ear, it's a piece of equipment used by auto techs to track down noises. It has 6 leads with alligator clips to attach to the component in question and the leads go to a box with a selector knob to select which channel to listen to and a set of headphones plug into it.
Here's my situation, I have one of these that I'm pretty sure the box went bad on it and I have long since gotten rid of it. (wish I hadn't) Now what I'm trying to do is build another one so I can use this tool again.
I recently bought a Radioshack electronics learning lab and found a way to amplify the signal using a 272 OP-Amp and then further amplify that using a 386 audio amplifier. I have substituted the alligator clips from my Chassis Ear with this circuit and it works great but I'm concerned about the current this setup will use seeing as how it will be powered by a single 9 volt battery.
From what I remember of the old box, I don't remember seeing any IC's so I was thinking it might have just used a couple transistors to amplifiy the signal. Even if I have to use an IC to amplify the signal I've read that I could substitute a small transformer for the 386 amp to cut back on current.
So what do you guys think? Am I on the right track with this or do I just sound like a complete idiot Any thought or opinions would be greatly appreciated.