a) Triode valve characteristic apparatus :- the instrument is designed to work on 230 volts a. C. It consists of power supply of its own, fitted with triode valve 6. 15 one dual range meter (out of two meters provided in this apparatus) is provided for ht volts and current with the help of a toggle switch and other of bias volts. output :- h. T. 0-300 volts dc at 30 ma continuously variable. bias 0-15 volts dc at 5 ma continuously variable (reversible ) 
b) Triode valve characteristic apparatus stabilized :- same as above but with stabilized power supply. 
c) Triode valve characteristic apparatus :- same as above but with three meters 
d) Triode valve characteristic apparatus power supply :- provided with power only having two meter output 0-300 volts dc at 30 ma continuously variable bias 0-15 volts dc at 5 m. Amp continuously variable. 
e) Triode fleming apparatus :- a triode valve is fitted on board with circuit diagram. The connections are brought out for anode, heaters and cathode. The same is used with above type of power supply

A)  Diode valve characteristic apparatus :- this instrument is designed to work on 230 volt A.  C.  It consists of a power supply of its own.  Fitted with diode valve on the front panel.  Two meters are provided to read to voltage / current.  This apparatus is very useful for plotting the characteristic curve of a diode valve.  This instrument is built in steel box nicely painted.  Output h.  T.  :0-250 volts at 25 milli ampere continuously variable L.  T.  : 6.  3 volts ac built in rheostat for filament current control. 
B)  Diode valve characteristic apparatus stabilized :- as above but with stabilized power supply. 
C)  Diode valve characteristic apparatus power supply : input : 230 volts a.  C output : 230 volts a.  C output : 0-25 volts at 25 ma l.  T.  : 0-6.  3 volts a.  C two meters are provided to read volts and ma built in a nicely polished box. 
D)  Diode fleming apparatus :- a diode valve is fitted on board with circuit diagram.  The connections are brought out for anode,  heaters and cathode.  The same is used with the above type of power supply. 

a) Bridge Oscillator :- A spot frequency for bridge experiments workable on 220 volts, 50 Hz giving variable output 0-20 volts RMS at 1000 Hz Accuracy + 2% output impedance 600 ohms. 
b) Bridge Oscillator :- Same as above but solid state output 0-6 volts

a) AF Oscillator :- (20 Hz to 200 K Hz in four bands) Sine and square wave with output level meter 0-10 VP.-P. output impedence 600 ohms. b)Function Generator solid state :- (1 Hz to 100 K Hz in five bands) Sine square and triangular wave with out variable from 0-20 volt P-P. Accuracy + 3% Out impedence 50 ohms. c) R.F. Oscillator :- Variable 100 KHz to 30 MHz giving modulated output & continuous wave from The Modulation frequency 400 Hz. And is also available on output terminals. Modulation depth 30% Accuracy + 2%

L.C.R. Bridge :- a) Fully solid state instrument, workable on 220 V 50 Hz or on 9 volts Battery, useful for the wide range measurement of Resistance and Inductance. b) Resistance Range ; 0.01 Ohms to 1 Meg Ohms in seven ranges, Capacitance 2 PF to 110 MFD. Inductance 2 micro Henries to 110 Henry in seven range D- 0.001 to 10 Q – 1 to 10. c) Test Frequency 1 KHz. Accuracy + 2% for Inductance and + 1% for condenser and resistance

A) Semiconductor diode characteristic apparatus : consisting of a semi conductor diode oa 79 provided with terminals for each electrode fitted on black front panel with built in two power supply. output bias :- 0-2 volts dc continuously variable and 0 to 20 volts dc continuously variable. a toggle switch is provided to reverse the polarity of the provided semiconductor diode complete with two meters.
b) Semiconductor diode characteristic apparatus :- same as above but with four meters.
c) Semiconductor diode characteristic apparatus :- same as above but with three deluxe meters.
d) Semiconductor diode :- as a half wave and full wave rectifier complete with two meters.

Vacuums tube voltmeter model :- as electronic D. C. Voltage 7 ranges 0-1. 5, 5, 15, 50 150, 500 and 1500 volts F. S. D. 
a)  Accuracy : + 3%
b)  Input impedance 11 meg ohms
c)  As electronic A. C. voltmeter: 7 range 0-1. 5, 5, 15, 50, 150, 500 and 1500 volts F. S. D. 
d)  Accuracy : + 5 %
e)  Input impedance : 1. 5 meg ohms
f)  As electronic ohm meter: 7 ranges 0-1000, 10000, 100000 ohms and 1, 10, 100, 1000 meg ohms F. S. D. 
g)  Accuracy : + 3%
h)  Meter : simpson 1 ½” with transparent cover
i)  Input: 230 volts a. C. 50 HZ.

Multimeter :- A very useful instrument for measuring resistances, voltage, current in apparatus etc.