I have a battery pack with 17 AA 2000 mAH NiMH batteries. I built a charger with two LM317T chips. The first one was set to limit the current to 250 miliamps (5 ohms} per hour and the second to set the voltage at 22 V, a simple adaptation following the datasheet. I used a 270 ohm(220 and 47 in...

I started with what I thought was a very narrow technical question. And you guys have correctly pointed out the assumptions and choices behind it. I can't vouch for this company's batteries. I'll put one across a precision resistor and check the run time. I couldn't find cheap name brands...

I have found a pretty good price on some AA NiMH with solder taps at http://www.batteryspace.com/index.as...ROD&ProdID=222 So the question is, How do they go together? Do I solder tab to tab or put a wire through the holes in the tabs? Or I could solder tab to tab for those in a straight line...

Thanks for the help, especially pointing out the search feature. I'm still learning my way around this neighborhood. Dave

I've been figuring out where to get parts for a Pimeta build and I'm set to pull the trigger (except I want to stew on the enclosure for a bit) but I can't find this chip in stock anywhere. Newark, Jameco, DigiKey and Mouser are all out of stock. What the hey? Anybody have a solution? Dave

Anybody familiar with these kits? http://www.web-tronics.com/lowcosunbatc.html and they have a fancier one. The fancier one looks good but it has an automatic discharge feature which is OK for NiCd but shouldn't be used for NiMH, right? Is it possible to turn that feature off? What about the...

Where can I get a cable to hook my Ipod up to my amp which has a mini input? I see Mini to RCA but not mini to mini (male to male) of short lengths.

I realize that it can be biased into class A operation. But are there other differences? Dave

Does this amp have anything between the opamp and the headphones? The picture of the amp is a bit fuzzy but I see no IC's or active components other than the two opamps. So it has lots of capacitance and I like the idea of crossfeed (newbie who's never heard a headphone amp), but otherwise it...

Some parts I've gotten for this amp come in ESD safe bags. I know that some computer boards can be damaged by static, but can opamps, JFET's or buffers? Even the boards came in such protection and static can't be an issue for a board. Thanks for the help with my newbie question. Dave

Thanks for the help. Dave

"R7 Just in case you're familiar with the META42 or PPA, there is no series resistor between the op-amp and the buffer since the BUF634 has 200 ohms of series resistance on its input already. Hence, there is no "R7". R8" This is from Tangent's Part Selection guide for the Pimeta. I may be...

What function do the output buffers perform when driving 300 ohn cans? In the explanation of the circuit, Tangent notes that the opamp is looking at 200 ohms in the input of the buffer. If the buffer sees 200 ohms in the cans, how does it help? One member got by my screw up in first asking this...

What does the Pimeta buffer do for high impedance cans? I'm trying to build a Pimeta and am a bit confused. I took an electronics course about 20 years ago and have assembled a couple of kits so I know how to solder, but my understanding is pretty limited. In the explanation of the Pimeta it...