Nieuw project Hulp nodig?
Laatste reacties
mfc 18 uur geleden
Agreed.   An update from me -- I ordered a second MEMS microphone BoB and with this one the setting of P2 worked as expected (albeit only changing behaviour at about one turn above 0).  However, with this second microphone board  (and a third which I wanted to put on a longer lead) I did not add the decoupling capacitor on the microphone board. So my current hypothesis is that the MEMS board with decoupling capacitor is just "not noisy enough" for the P2 setup to work .   I'm just off on a trip where I'll be using the detector in caves, but when I get back in a few weeks I'll try adding the decoupling capacitor to the 'working' MEMS board and see how that affects the circuit. Very many thanks to all who posted here, and to Ken Horton who suggested getting a second MEMS board.   At present I have a device that works as described in the article. Hmm .. wonder if a Rev3 might be in order?  Single-rail op-amps to avoid the need for level shifting; maybe more done in software;  maybe stereo .... ?  
Bat detector with amplitude recovery
Elektro Maker
Elektro Maker 19 uur geleden
To have a MIDI IN compatible with older 3.5mm jack interfaces, leave off D1 (BAT54) and solder an H11L1M piggybacked on IC1 (H11L1MS) with pins 1 and 2 swapped (pin 4 is an open collector output).
MIDI I/O Break-out Board [190070]
TonGiesberts 1 dag geleden
RF Power Meter (mother board) -bare PCB (160193-2)   RF Power Meter (RF front-end board) - module (160193-91)   or instead of the front-end module RF Power Meter (RF front-end board) - bare PCB   and all part as listed in the BOM in the article RF Power Meter For measurements up to 10 GHz Here the software needed for the Arduino Nano can be downloaded. You have to program the Arduino Nano yourself!  
RF Power Meter with seperate RF break-out-board [160193]
TonGiesberts 1 dag geleden
The maximum input offset of a TL062CP is 15 mV. That's high and maybe the cause different builds of the bat detector using the same components show different sensitivity. This high offset makes the TL062 C not suitable for use as a comparator. The signal from IC3A has first to equalize the offset before tripping the output of IC3B, thus making it less sensitive when the hysteresis set with P2 is very small or 0. A contemporary low power/low bias current/low offset opamp would be preferable for IC3.  
Bat detector with amplitude recovery
Thomas Bunge
Thomas Bunge 1 dag geleden
New forms and header files.
HV Power supply with tube and semiconductor curve tracer