RF sensing alarm is a device that would alert when it detects a continuous RF transmission that lasts more than 5 minutes. The device would have to be broadband (HF/VHF/UHF), be sensitive enough to detect a 5W transmission from inside the shack using a...
Topics: Sensor

{"title":"RF Sensing Alarm","post_url":"http:\/\/schematronics.blogspot.com\/2008\/10\/rf-sensing-alarm.html","feed_url":"http:\/\/schematronics.blogspot.com\/feeds\/posts\/default?alt=rss","author":"broadcasthardware","date":"2008-10-30 22:40:00","summary":"RF sensing alarm is a device that would alert when it detects a continuous RF transmission that lasts more than 5 minutes. The device would have to be broadband (HF\/VHF\/UHF), be sensitive enough to detect a 5W transmission from inside the shack using a..."}

This electronic circuit is an oxygen sensor simulator that built on a protoboard by Bob Blick. Note the cigarette lighter plug used for power source. The adjustment knob is at the left, and the switch is on the right. The red indicator LED is in the...
Topics: Sensor

{"title":"Oxygen Sensor Simulator","post_url":"http:\/\/schematronics.blogspot.com\/2008\/07\/oxygen-sensor-simulator.html","feed_url":"http:\/\/schematronics.blogspot.com\/feeds\/posts\/default?alt=rss","author":"broadcasthardware","date":"2008-07-13 16:08:00","summary":"This electronic circuit is an oxygen sensor simulator that built on a protoboard by Bob Blick. Note the cigarette lighter plug used for power source. The adjustment knob is at the left, and the switch is on the right. The red indicator LED is in the..."}

The ESR Meter is basically an AC Ohmmeter with special scales and protective circuitry. It provides a continuous reading of series resistance in electrolytic capacitors. It operates at 100 kHz to keep the capacitive reactance factor near zero. The...
Topics: Meter-Measurement

{"title":"ESR Meter","post_url":"http:\/\/schematronics.blogspot.com\/2008\/07\/esr-meter.html","feed_url":"http:\/\/schematronics.blogspot.com\/feeds\/posts\/default?alt=rss","author":"broadcasthardware","date":"2008-07-10 09:27:00","summary":"The ESR Meter is basically an AC Ohmmeter with special scales and protective circuitry. It provides a continuous reading of series resistance in electrolytic capacitors. It operates at 100 kHz to keep the capacitive reactance factor near zero. The..."}

This electronic circuit is a tiny pH-meter. It is very tiny: 11cm2 including the PSU circuit! The schematic is shown below. It is basically a simple gain/offset circuit with a high impedance input (several giga-Ohm) and frankly the explanation could stop.
Topics: Meter-Measurement

{"title":"A Tiny and Accurate pH-meter","post_url":"http:\/\/schematronics.blogspot.com\/2008\/07\/atiny-and-accurate-ph-meter.html","feed_url":"http:\/\/schematronics.blogspot.com\/feeds\/posts\/default?alt=rss","author":"broadcasthardware","date":"2008-07-05 18:08:00","summary":"This electronic circuit is a tiny pH-meter. It is very tiny: 11cm2 including the PSU circuit! The schematic is shown below. It is basically a simple gain\/offset circuit with a high impedance input (several giga-Ohm) and frankly the explanation could stop."}

The electronic circuit is Temperature Sensor with I2C program. It is a circuit that plugs into the link port of a TI-85, TI-83, or TI-92 calculator and displays the temperature on the screen. Currently, there is only software for the TI-85, but I plan...
Topics: Sensor

{"title":"I2C Temperature Sensor","post_url":"http:\/\/schematronics.blogspot.com\/2008\/07\/i2c-temperature-sensor.html","feed_url":"http:\/\/schematronics.blogspot.com\/feeds\/posts\/default?alt=rss","author":"broadcasthardware","date":"2008-07-01 00:12:00","summary":"The electronic circuit is Temperature Sensor with I2C program. It is a circuit that plugs into the link port of a TI-85, TI-83, or TI-92 calculator and displays the temperature on the screen. Currently, there is only software for the TI-85, but I plan..."}