Crystal Tester And Frequency Counter TS-905

Note: this is not an in-depth test. The instructions, layout diagram, parts list, and schematic are shown at the end of the video. This test instrument seems to be based on the PIC 16F628 microcontroller. Further information is available here: https://www.qsl.net/dl4yhf/freq_count... Oddly enough, the instrument performed much better after I played around with the programming switch. Overall I would say It was worth the money, although I did not really need it; more like a gadget. The crystal socket sits too deep once the case is put together and some of the screws seemed too short, at least for me. Also, this is not a high-resolution counter; when I fed a 111,000 Hz sine wave into the frequency counter, I read 11099; I could only guess that it was within 10 Hz.