There are times when you would like to flash a LED through a thick plastic case without wires. The circuit below performs this feat. It can be powered from a supply ranging from 3 V to 6 V. It draws about 300 µA of average current at 5 V. It ...
This basic beat oscillator makes continuous wave keyed code and single sideband suppressed carrier signals audible. A recent Design Idea from contributor Gavin Watkins shows an inexpensive add-on beat frequency oscillator (BFO) [ 1 ] for ...
Expensive shortwave radios include beat frequency oscillators, so why not also add one to an inexpensive radio version? Broadcast shortwave (SW) radio use may be declining, but there are still lots of interesting signals to listen to between 1.6 ...
New TCAN6062 CAN XL transceiver delivers the highest bandwidth and largest payload of any CAN-based network while preserving the advantages of proven CAN protocols What’s new? Texas Instruments (TI) introduced the industry’s first ...
The frequency response of a Butterworth filter is not supposed to have any peaking. SPICE claims the contrary. I came across an online datasheet for some op-amps where I found two schematics that intrigued me. Screen-shotting them together resulted ...
This circuit enables you to generate remote control PWM test signals with a (very) generic (and cheap) chip. A recent Design Idea ( Ref. 1 ) illustrated the application of an interesting chip (the LTC6992 ) to remote control (RC) PWM test signal ...
Self-heated Darlingtion transistor pair linearly senses airflow using just two wires for both power in and signal out. Suppose we take a common TO-92 transistor and heat it to a constant temperature differential above ambient. The power input ...
Minimal circuit converts input frequency to a precision current source that also accommodates grounded inputs. I recently had the opportunity to share a design ( Ref. 1 ) for frequency to current loop conversion using the versatile (if somewhat ...