The FK 181 Sound Level Meter kit  is similar to a VU in concept.  Normally supplied with  10 red LEDs, users may subsitute LEDs of different colours to suit their own applications.  The FK181 normally takes its sound signal from a supplied electret microphone but the same circuit may be used with DC sources by by-passing the input capacitor  The sound level, once established may be "held" for comparison with readings from different locations.

The FK903  is a really low cost signal source for testing continuity and functionality in cables, amplifiers and relay networks. The FK903 features two switched audio signals, 500Hz and 1kHz, which are easily recognised against background noise.The signals may be picked up using our economical FK602 2W amplifier with a speaker or earphone
Power supply 3V @ 1mA
Signal level 2.6V Max
Dimensions 40.4mm x 40.6mm x15mm
Recommended Housing FB03

FK907  In-Circuit Transistor Checker.  There are times when removal of a transistor from a PCB to check its functionality is not practical. The FK907 transistor checker can examine both NPN and PNP transistors whilst installed. Two, on-board LEDs are used to identify the transistor type and whether or not it is functional.
Power supply: 9VDC @85mA
Dimensions:  62.28mm x 30.7mm x 15mm

Quad Pack FK908 Soil Moisture Indicator. Great as a Schools Project -  Two probes in the soil sense the soil resistance as a function of moisture content. The FK908 can be used as a portable device or installed permanently in agronometric situations.  Alarm outputs and Audio signals may be added. 9V operation  Unbeatable Value - Four Kits for the price of one!!

FK909 Audio Continuity Tester This simple test unit gives a rapid and audible indication of resistance in home appliances and industrial wiring between 1.0 Ohm and 500KOhm. The resistance of the circuit under test forms part of an oscillator in which level and frequency are inversely proportional to the circuit resistance. The FK909 may also be used to detect moisture content.
Power supply9VDC @150mA
Dimensions 29.46mm x 35.4mm x 15mm

The FK912 uses a photo-transitor as the light measurement element. A transistor amplifier drives an array of 5 LEDs in proportion to the light level received. If measurement relative to backgorounfd condistions is required, an on-board potentiometer is available to compensate for ambience. Interesting student project - class time approximately 45minutes.

FK924 DC Voltmeter 0-1000V This compact meter project uses a Large Scale Integration IC (LSI to minimize component count and assembly complexity. The FK924 is scaled for the range 0-1000V which is displayed on a 4 Digit LED readout.
Power supply 7-15V. 120mA (max.) at 12VDC.
Dimensions: 67.56mm x 68.58mm x 25.6mm

FK925 AC Voltmeter 0-500V This compact meter project uses a Large Scale Integration IC (LSI to minimize component count and assembly complexity. The FK925 is scaled for the range 0-500VAC  which is displayed on a 4 Digit LED readout.
Power supply 7-15V. 120mA (max.) at 12VDC.
Dimensions: 67.56mm x 68.58mm x 25.6mm

The FK939 is designed to check the voltage of a 12V battery whilst under load conditions. Applications include, back-up supplies for fans, computers, pumps and lighting.  The FK939 can be used to give a continuous readout. The FK939 will assist operators to detect critcally low battery discharge levels and thus take action to prevent damage due to over-discharge. The FK939 incorporates short circuit protection and features trimmer adjustment for each displayed voltage level.
Power Supply: 12VDC @ 56mA
Size: 96.3mm x 62.7mm x 15mm

The FK944  Works on the principle that the resistance of water reduces in accordance with the percentage of salt and other contaminants.  The 8 LEDS display the relative conductivity of the water or stream.  For example the green LEDs suggest a lower level of contamination than the red LEDs. This kit was designed as a school project, and as such ids ideal for class discussion about the environment or testing for salt levels in streams and lakes whilst on school field trips.
Power Supply: 9V @ 8mA (standby) and 21mA (working)
Level Indication: 8 LEDs
Sensitivity: 3 Switched Level Selections
Dimensions: 70.6mm x 45.15mm