Really cheap USB oscilloscope, spectral analyser, logic anal
Check this out the new cheap handy tool for multi purpose works. Poscope is affordable (now for 70EUR) instrument that includes:
2 channel Oscilloscope with markers, triggering, filtering etc.;
2 channel Spectral analyser with markers, filtering etc ;
2 channel Chart recorder with markers (up to 99), recording with up to tens of hours etc;
16(8) channel Logic analyser with markers, various triggering, external clocker, decoding UART, SPI, I2C 1-wire interfaces;
8 channel Logic generator with ability to plot signal with mouse, etc.;
Coming Square generator.

As it is said this is handy and cheap tool for researching any electronic devices. The parameters arent very high a€“ as oscilloscope sample rate is up to 200kHz, but for most hobby purposes this is enough.
Interface is simple and easy understandable:

Additionally this scope is able to save results to vector graphic or BMP format, print results, copy to buffer, save events and sounds, calculate and perform filtering, display statistics for all channels. Device is upgradable with future features and bug fixes. Read more in PoScope developers site.
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http://www.scienceprog.com/really-cheap-usb-oscilloscope-spectral-analyser-logic-analyser-and-generator/
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