Patent GB-1000281-A (GB)
Title: Test equipment for electronic assemblies
IPC: G01R31/28
Filed: 1963-01-14
Abstract: 1,000,281. Faultstesting; Local circuits for electric meters. BENDIX CORPORATION. Jan. 14, 1963 [Jan.15, 1962], No.1607/63. Headings G1Q and G1U. [Also in Division H2] A universal tester for dynamic and static tests on the operating efficiency of electrical apparatus such as multiterminal electronic circuit modules comprises means establishing separate electrical contacts with each of the multiple terminals, means generating plural adjustable electrical excitations; plural indicators selectively connectible to appropriate electrical contacts and respectively measuring an electric quantity such as D.C. average voltage, or average current in relation to a corresponding terminal with one indicator corresponding to the input and the other to the output of the tested apparatus; and plural switches for selective connection between the indicators, the electrical contacts, and the electrical excitations; the plural switches including first switching means selectively applying the several excitations to input terminals of the apparatus under test, second and third switching means respectively and selectively connecting one indicator to monitor the excitation applied to the input of the apparatus under test, and another indicator to monitor the electrical energy at the output of the apparatus under test. Socket panel and patchboard An electronic module M (Fig. 1) is plugged into an appropriate socket adaptor 11 fitting a 48 contact socket adaptor plugged into mating socket panel 3 having terminals S 1  to S48 (Fig. 2) which are wired to corresponding sockets P 1  to P 48  of patchboard 4 (Fig. 3) and over conductors C101 to C148 to corresponding arms TC 1  to TC 48  of an array of 48 toggle switches T 1  to T 48  whose "up" and "down" positional contacts are wired to B busbar 12 and A bus-bar 13 respectively. Sockets P49 to P54 of the patchboard are connected to corresponding manually adjustable outputs 61 to 66 of a D.C. power supply 1 (Fig. 1) over conductors C49 to C54, and sockets P55 to P64 of the patchboard are connected over conductors C55 to C64 to respectively a common voltage bus-bar 18 energized from the power supply, a switching gate circuit 9 described below, the B bus-bar 12, the A bus-bar 13, an external terminal connection 17, the negative of an input indicator 6 described below, the negative of an output indicator 7 described below, conductor C62 and C63 left open for future expansion, and to a switchable load circuit 8 (Fig. 2) described below. The required terminals of the test module are connected serially to the sockets of panel 3, unused sockets being left unconnected; while the patchboard enables any two or more test module terminals to be jumpered together either directly or through L, C, or R circuits by insertion of appropriately connected plugs and conductors. The modular terminals may similarly be jumpered as required to the variable supply voltage appearing on sockets P49 to P54 to common voltage on socket S55, or to any selected switching and reference circuits appearing on sockets P56 to P64. A-B selector switch bank and variable load circuit. Each toggle switch T to T48 enables a selected modular terminal to be connected to the A or input bus-bar 13; to the B or output bus-bar 12, or to be left disconnected. The bus-bars are connectable to a load 8 wherein a manually variable resistor 31 is connected through bridged external measurement terminals 33, 35 and external measurement terminal 36 to manually operable selector switches 37, 38 of which 37 selects the A bus at L10, the B bus at L12, the switching gate 9 at L15, socket P64 of the patchboard at L16 and a blank position at L17 while 38 selects a blank position at L20, variable voltage power supplies at L21 to L26 and common voltage bus-bar 18 over L27. Terminal 36 enables the connection of external motors or oscillographs, while terminals 33, 35 may be opencircuited and connected to indicators 6 and 7 over conductors L2, L3. In mode selector switches. The A and B bus-bars are respectively connected over shortcircuited terminals 74, 75 and 76, 77 to rotary selector switches 15,16; removal of the shorting links enabling respective measurements of the bus-bar currents by indicator 6 and 7 over conductors C174, C175 and C176, C177. Each selector switch is manually operable to connect the A and B bus-bars 13, 12 respectively to the output bus-bar 10 of function generator 2 over contacts C73, C83; to the inverted output 21 of the function generator over C74, C84; to outputs 62, 63 of the power supply 1 over C85, C86; C75, C76; to the external terminal 17 over C77, C87; and to the common voltage bus-bar 18 over C78, C88. Excitation. D. C. power unit 1 (Fig. 1) provides six manually variable positive and negative voltages at terminals 6 to 66, and function generator 2 produces manually selectable step and pulse voltages triggered by switch 19, a 1 c.p.s. squarewave train, and a 200 kc./s square wavetrain adjustable in the positive to negative and negative to positive series by manual controls of attenuator 20 providing a floating output superimposed on a bias variable by resistance 22 there being also provided an invertor 21 reversing the output. The outputs are carried on bus-bars 10, 39 to appropriate points of the apparatus. External excitation is applicable to terminal 17. Input and output indicators. In Fig. 7 a meter movement in parallel with resistor 11 is connected through series resistor 12 across shunting diode 13 protecting against overloads exceeding full scale deflection and is provided with a manually operated rotary switch 14 engaging contacts 120, 24, 28, 32, 36, 40, I21, 25, 29, 33, 37, 41 to select a range of series and shunt resistancies so that the meter operates as a multirange milliammeter and voltmeter having one range variable by manually variable resistor 142 connected to contact I41; the positive output connection being taken to the manually operable selector switch 24, whereby connections may be respectively made over I102, 104, 106, 108, 110, 112 to terminals 61 to 66 of the power supply; over L3 to load 8; over I116 and I118 to A and B bus-bars 13 and 12; over I120 to the common voltage bus-bar 18; over C174 to terminal 74; over I124 to external terminal 17; and over I126 to terminal 861 of the switching gate circuit 9. Similarly the negative output connection is taken to the manually operable selector switch 25 whereby connection may be made respectively over I132, 134, 136, 138,140, 142 to terminals 61 to 66 of the power supply; over L2 to load bus-bar 8; over I146, I148 to A and B busbars 13, 12, over I150 to common voltage bus-bar 18; over C175 to terminal 75; over I154 to external terminal 17; over I156 to terminal 862 of the switching gate circuit 9; and over 160 to socket P60 of the patchboard 1. A similar output indicator (Fig. 8) is provided; the positive side of which is selectively switchable to terminals 61 to 66 of the D.C. power unit; to terminal 35 (Fig. 2) to A and B bus-bars 13, 12 to common voltage bus-bar 18; to terminal 76 (Fig. 3) to external terminal 17, and to switching gate 9. The negative side is similarly selectively switchable to terminals 61 to 66 of the power unit; to terminal 33 (Fig. 2) to A and B busbars 12, 13; to common voltage bus-bar 18; to terminals 77 (Fig. 3); to external terminal I17 (Fig. 1); to switching gate 9; and to socket P61 on the patchboard 4. The motors carry two manually adjustable flags e.g. 93, 94 referencing logic zero and logic one levels when a module utilizing binary coding is tested. Switching gate. Fig. 9 shows a switching gate (Fig. 1) affording direct access to any socket of the patchboard and thus to any terminal of a module under test, and comprises two back to back connected rotary switches 80, 81 which are manually operable. Switch 80 has 48 contacts legended G1 to G48 connected over conductors C201 to C248 to the corresponding arms TC1 to TC48 of the toggle switches T1 to T48 in the A B selector bank 5 (Figs. 2, 3). Switch 81 has 17 contacts legended 851 to 867 respectively connected to terminals 61 to 66 of the power supply 1 to the function generator bus-bar 10 (Fig. 1); to the A and B bus-bars 13,12; to the load 8; to contacts I125, I155 of selector switches 24, 25 (Fig. 7) to contacts I225,I255 of selector switches 29, 31 (Fig. 8); to external terminal 17 (Fig. 1); to common voltage bus -bar 18 and to socket P56 of the patchboard 4 (Fig. 3). The arms of the selector switches are interconnected through a resistor 82 preventing accidental shortcircuits, which is shunted by pressel switch 83. The various meters and switches are arranged on a panel assembly (Fig. 10 not shown) with the meter dials adjacent and by suitable combinations of switching and jumpering of the patchboard it is possible to apply any required voltage of any required polarity to the several terminals of a test module up to a maximum of 48, to apply individual pulses or steps of voltage or low or high square pulse trains thereto, and observe consequent output variations, to measure the input and output voltages or currents of any selected circuit of the test module, to test circuit continuity, and to check or calibrate the individual voltage and current sources of the apparatus. Examples of testing the operation of flip-flop multivibrator and of an AND gate circuit of multiple input, are described.