SCPIDecimator

Observing the travel of light
The falling edge of a single bit on a couple of cm long 115200 kbps UART connection between a 4D Systems OLED and a bluetooth module.

two more cables in between → longer signal propagation time: 3×108 ms-1 (4.2×10−9 s − 1×10−9 s) ~ 1 m


Bandwidth test with NEC 78K0 PWM
RIGOL RP2200 probe @ 10× with ground lead

Ground spring

Resistive Z0 probe @ 100× built from old 10Base2 T adaptor, terminator, 3 m RG-58 cable and 4.7 KΩ metal film resistor

@ 50×, 1.5 m RG-58 cable and 1 KΩ carbon composition resistor


The character A (01000001→10000010) from a FT232R at 269531 bps. Cursor: 1 start + 8 data = 9 bits → 3.71 Ás/bit → 269461 bps

Bit-banging at maximum speed with a FT245R


Measurements with a SFH 213 photodiode
SyncMaster 244T BLU

Chromoflex 3 LED controller

DLP Link


ELV S 2001 ID captured with shorted 1X probe

Zooming and averaging reveal the 433 MHz ISM carrier


DS1054Z calibration signal


SCPI Decimator
Sven Killig 2010, 2012, 2013