Oz DIY-WB WB Unit

This is version 1.0 of the Oz DIY-WB true wideband oxygen content controller that is used with the inexpensive NTK L1H1 UEGO 5 wire sensor. It features automatic calibration using the sensor's calibration resistor, fast warm up (typically 30 seconds) and may be connected to the 5301 digital meter to read in AFR or Lambda. It is ideal when a low cost AFR meter is required for general purpose tuning.

The unit, with power cable, weighs around 400 grams (just under 1 lb.). The tough ABS plastic case measures 150 x 80 x 30 mm (5.9" x 3.2" x 1.2"). The standard power cable is over 2 m long (over 6 feet).

The circular connector mates to the NTK L1H1 UEGO sensor via a 2.6 or 4.0 m cable. The DB9 male connector provides a non linear Vout signal between 1.4 Volts (representing AFR 10.1:1) and 3.1 Volts (25:1). The red LED indicates that the heater is up to operating temperature.

The unit requires a minimum of 13.2 Volts for correct heater operation (normally the unit is wired direct to the vehicles harness as cigarette lighter outlets are notoriously unreliable in operation).

The sensor is ideally located in a new bung welded into the exhaust system (always before the cat). Is can be used in a hand held holder to measure post cat oxygen content although, unless precautions are taken, this position is not recommended.

Manufacturing the Oz DIY-WB

Here's a shot of an early production run of WB units and a few 5300 displays too.