I’ve built an FM microphone bug or transmitter before, but it’s been a very long time since I wound coils for one. Long ago I would wind too many turns on the coil and try it out. The usual outcome was the bug would be transmitting somewhere in the low TV channels 5 or 6,
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I received an email from Peter, who has planned on building a SSTC, solid state Tesla Coil. Peter gave me permission to post this email discussion to my blog. I have redacted some information for privacy reasons. “From:”Peter Bergmann” Date:Wed, Mar 23, 2016 at 5:31 PM Subject:It´s alive!! Dear Watson, since I just can´t get
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Wow! Red hot metal in just a few tens of seconds! Peter has been experimenting with a MOT ( microwave oven transformer) with a rewound secondary that puts out 26 volts at up to 1000 watts. He fed this into an 80v, 35 amp bridge rectifier and a bank of 4700 uF at 35 volt
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I think I built one of these years ago but it must be buried in a box somewhere, probably in a pile of boxes in the garage. It’s a FM microphone transmitter, of which I have several, built from kits and from scratch. But this one was unique in that I built it with a
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I noticed my fellow group members in the Yahoo Group RegenRX are often using a 9V battery to power their projects. This blog is a way to save them a lot of money if they use a lot of 9V batteries. First, the 9V pro’s and con’s, then the DC-DC converter pro’s and con’s. For
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Leonard Meek came up with this regen receiver that uses a vacuum tube for the RF section and the ever popular LM396 for the audio section. I decided to write my concerns about this circuit in this blog. This schematic was posted to the files section of the Yahoo group Regenrx2 (Regenrx Overflow). One major
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I’ve been thinking about the garage door open alarm project of an earlier blog, and how to get the alarm signal from the door to wherever the alarm beep signal is going to be heard. The distance isn’t far: less than fifty feet or fifteen meters. There are some interior and exterior walls in the
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I received a Google Alert about this regenerative receiver schematic being posted to the RegenRX Yahoo Group (you may have to be logged on the view it). It’s quite complex for a regenerative receiver – the average regen set has just a few transistors. But its Achilles Heel is the front end. When I was
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I had already built one of these several years ago, and since I’ve used it to test the crystals that I’ve salvaged. It’s a simple circuit, using only a single transistor to make a Colpitts Oscillator with the two leads for the inductor run to terminals so that various inductors and coils can be connected
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I’ve thought about this a number of times in the recent past. There used to be a .ZIP file on the ‘netcalled Xanadu Zapper which consisted of plans and code to implement an IR xmit/recv interface for the PC along with code for learning and sending the IR codes. Many years ago I built the
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