When I googled I found a ‘stereo input’ FM transmitter. Most of the FM ‘bugs’ on the web and YouTube have a microphone. The circuit I linked to has left and right inputs, but mixes them to make a monophonic (not stereo) signal. After looking at the schematic I noticed a mistake, so I thought
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I put this AA cell, which measured 1.3 volts – ‘dead’ – on one of my germanium Joule Thiefs more than a week ago. It was glowing very brightly for a few days. For the last few days, it has been weakly glowing, and the Kirkland AA cell is still hanging in there, even though
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from a comment I added to this YouTube video https://youtu.be/GCh2LVHUavQ The main difference between a power transformer and an audio transformer is the way the E and I laminations of the core are arranged. The power transformer has an E on the left and I on the right of the first layer, then an I
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Read update at the end first. I was searching for some regenerative receiver schematics and looked at some other circuits. Google says similar images, but it doesn’t know anything about the purpose of the image, it just knows that it has lines connecting different symbols, and even then I’m not sure if it even knows
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I was considering what I would do if the electricity went off and I needed to solder something. I was on YouTube and I watched a guy make a battery operated soldering iron from copper wire, part of a telescoping antenna, wood, fiberglass sleeve tubing, some 0.2mm nichrome wire, and battery and holder. The video
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The LCD on my digital thermometer faded away, so I knew that it needed to have the single AAA cell replaced. I bought the indoor/outdoor thermometer probably more than two decades ago from Radio Shack. This time, I removed the AAA cell and I had marked it as installed in Nov of 2005, so it
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I was coming back from lunch, walking through the parking lot of the shopping center across 17th St from the college. I saw Pat Ewing also walking several rows away. We were both headed for the crosswalk at the front entrance of Santa Ana College. All of a sudden this pickup pulls into the parking
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Continued from 2016-09-03 post. Back to the light bulb. To clarify, we are only discussing the original incandescent light bulbs, not the newer ones. This also applies to the 115 volt AC light bulbs. Other voltage lights would have to use different values. Warning! Also you indemnify (hold me harmless), me, the author, against any
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I had a hard time editing the reply to #2 of the comment, besides it’s a good blog. The following applies to my Supercharged Joule Thief. But you really don’t need to use a MOSFET. Any PNP transistor, 2N3906 or BC557, will do the job, and the current will be relatively low. Replace the diode
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I have always thought that using ferrite toroid cores for radio projects at HFs and above was not necessary, because all of the RF circuit parts lists call for low permeability powdered iron cores. I’ve never given it much thought; about the only thing that crossed my mind was that the powdered iron cores may
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