Hickock 539C User`s Manual
Contents
1. 272 low the given striking voltage The meter indication for a good tube is above the point designated RECTIFIERS OK 18 Filament and Heater Continuity 1 2 3 4 5 Turn the tester on Set the selectors as per chart for the tube to be tested Set the FILAMENT switch on BLST instead of voltage indicated on the chart Set the SHORT TEST switch on position 5 Place the tube in the proper socket If the neon lamp glows the filament is good and a complete test should then be made on the tube by setting FILAMENT switch on the proper tap and while the tube heats rotate the SHORT TEST SWITCH several times thru 1 to 5 positions If no shorts are indicated set the switch in TUBE TEST position and proceed to test the tube as per chart If the neon lamp does not glow the filament is open and further test is unnecessary Certain tubes such as 3575 5077 etc with tapped filaments have special continuity test settings see roll chart NOTE It sometimes happens that a filament will show cont inuity when cold but will open when it warms up 19 Voltage Regulator Tubes a rh 5 09 mm Set the selectors for V R tube to be tested The test data for V R tubes will be found at the top end of the roll chart For example the 0A3 Set FIL VOLTAGE switch to OFF Set selector switches to AP 0502 0 Set function switch on range H V R TEST Turn the bias volts toggle switch to V R volts and mil2. TRANSCONDUCTANCE TUBE TESTER MODEL 539C THE HICKOK ELECTRICAL INSTRUMENT CO 1968 10514 DUPONT AVENUE CLEVELAND OHIO 44108 PNONE 541 8060 CABLE HICKOK CLEVELAND TWX CV 662 WESTERN UNION KJ WARRANTY The Hickok Electrical Instrument Company warrants instruments of its manufacture to be free from defects in material and workmanship for ninety 90 days from the date of original purchase Any instrument found to be defective during this period may be returned transportation prepaid to the factory for repair or at our option replaced without charge This warranty does not apply to any of our products which have been repaired or altered by unauthorized persons or which have been subject to misuse negligence or accident or which have had the serial number altered effaced or removed Neither shall the warranty apply where a warranty registration card has not been properly completed and returned to us promptly after purchase This warranty is in lieu of all other warranties whether expressed or implied RETURNING EQUIPMENT FOR REPAIR Before returning any equipment for service the factory must first be contacted giving the nature of the trouble Instructions will then be given for either correcting the trouble or returning the equipment Upon authorization this equipment should be forwarded directly either to the Hickok factory address at 10514 Dupont Avenue Cleveland Ohio 44108 or to a designated servi
3. 1 2 watt 18537 95 R51 RESISTOR FIXED FILM 200 ohms 190 1 2 watt 8537 76 R52 Same as R37 R53 RESISTOR FIXED COMPOSITION 220 K ohms 10 1 2 watt 8414 222 S1 SWITCH toggle spdt 9911 19 S2 SWITCH toggle spst 9911 9 S3 SWITCH rotary filament 9912 202 S4 SWITCH rotary 3 pole double throw 19912 304 S5 SWITCH gang pushbutton 19910 92 S6 Same as S4 S7 SWITCH slide dpdt 19911 7 S8 SWITCH toggle dpdt 19911 55 S9 SWITCH rotary function 19912 308 S10 Same as S8 S11 thru SWITCH rotary selector 19912 479 S15 516 517 SWITCH rotary suppressor and cathode 19912 480 S18 SWITCH rotary short test 19912 312 S19 Same as S8 VI TUBE 83 20875 28 V2 TUBE 5Y3 GT G 20875 6 X1 SOCKET 4 pin 9350 93 X2 SOCKET 5 pin 9350 94 X3 SOCKET 6 pin 9350 95 X4 SOCKET 7 pin 19350 96 X5 SOCKET octal 8 pin 9350 98 X6 SOCKET loctal 8 pin 9350 97 X7 SOCKET 7 pin miniature 9350 76 X8 SOCKET 10 pin 9350 364 X9 X100 SOCKET ASSEMBLY combination 7 8 pin 9351 16 X11 SOCKET nuvistor 5 pin 9350 336 X12 SOCKET novar 9350 367 X13 SOCKET compactron 12 pin 19350 365 X14 SOCKET nuvistor 7 pin 9350 382 ADAPTER socket 8 pin 050 39 ADAPTER socket 7 pin 050 41 BUTTON molded push black 2920 7 BUTTON molded push red 2920 8 DIAL ASSEMBLY shunt with knob 4160 66 KNOB ASSEMBLY bar type with pointer 11500 11 KNOB molded 1 dia 11505 49 LEAD ASSEMBLY plate 12450 145 LEAD ASSEMBLY 12450 180 SOCKET bayonet for 81 lamp 19350 1 T
4. 47 6 8 volts 15 amps miniature bayonet base clear 12270 12 DS2 LAMP NES1 neon 12270 14 E1 thru BAR shorting 2145 2 E3 F1 LAMP 81 bayonet type 115 volts 12270 2 F1 ILAMP 63 G E 230 volts 12270 58 J1 JACK pin plug type red 10300 1 J2 thru JACK pin plug type black 10300 2 J4 J5 thru BINDING POST black 2360 51 J10 M1 METER Line test Model 57MR 570 450 M2 METER Model 56R 560 812 M3 METER Model 68 680 302 P1 CORD AND PLUG ASSEMBLY 3 wire 3675 34 RI IRESISTOR FIXED FILM 150 ohms 1 2 watts 18540 4 R2 RESISTOR FIXED COMPOSITION 470 K ohms 10 1 2 watt 18414 472 R3 RESISTOR FIXED COMPOSITION 47 ohms 10 1 2 watt 18410 472 R4 RESISTOR FIXED 100 ohms 10 10 watts center tapped 18575 19 R5 RESISTOR FIXED COMPOSITION 15 K ohms 5 1 watt 18423 151 R6 RESISTOR FIXED COMPOSITION 1200 ohms 10 1 watt 18422 122 R7 RESISTOR FIXED 1800 ohms 10 10 watts 18575 12 R8 RESISTOR VARIABLE 50 ohms 16925 271 R9 RESISTOR FIXED FILM 300 ohms 1 1 2 watt 18537 99 R10 RESISTOR FIXED FILM 100 ohms 1 1 2 watt 18537 96 R12 RESISTOR FIXED FILM 50 ohms 1 1 2 watt 18537 65 R13 RHEOSTAT 350 ohms 15 25 watts 18750 7 R14 RESISTOR VARIABLE wire wound dual 3000 ohms and 1000 ohms 16925 270 R15 Same as R8 R16 Same as R14 R17 RESISTOR FIXED FILM 2250 ohms 1 1 watt 18539 12 R18 RESISTOR FIXED WIRE WOUND 8500 ohms 10 10 watts 18575 89 R19 RESISTOR FIXED FILM 1200 ohms 1
5. means that the top cap is connected to the GRID and P to the PLATE jack Special Notes Power line voltage varies with different localities It may also vary with the different hours of the day While a national survey indicates that the average voltage for the USA is 117 volts it does not mean that every locality maintains a constant voltage at that level Occasionally we have had the complaint that a used tube will test GOOD but will not work in the radio receiver but when a NEW tube is substituted the receiver will operate correctly The answer is this Tubes are built to specifications Our tube testers are designed to test tubes in conformity with these specifications The used tube that would not perform in a certain receiver was not receiving its specified filament voltage The new tube performed because of its initial reserve capacity The used tube would have performed if it had received its specified filament voltage Tube failure frequently occurs in A C D C sets where several tubes are connected with their heaters or filaments in series Sometimes even though the power line voltage is normal a series tube with abnormally high filament resistance will rob its companion tube of its normal filament voltage The robbed tube apparently fails but when tested under specified conditions the tube will test GOOD 6 15 16 17 The Model 539C is valuable in matching tubes for push pull stages and other appli cations w
6. 1 watt 18539 11 R20 R21 RESISTOR FIXED COMPOSITION 1000 ohms 5 1 watt 18422 101 R22 RESISTOR SPOOL 560 ohms 18684 124 R23 RESISTOR FIXED FILM 470 K ohms 1 1 2 watt 18537 66 R24 RHEOSTAT 1000 ohms 50 watts 18750 26 R25 RESISTOR VARIABLE 1000 ohms 16925 88 R26 RESISTOR FIXED FILM 150 ohms 1 1 2 watt 18537 64 R27 RESISTOR FIXED FILM 750 ohms 1 1 2 watt 18537 98 R28 Same as R10 R29 RESISTOR FIXED FILM 270 ohms 1 1 2 watt 18537 93 R30 RESISTOR FIXED COMPOSITION 10K ohms 10 2 watts 18433 102 R31 RESISTOR VARIABLE 10K ohms 20 2 watts 16925 495 R32 Same as R3 R33 RESISTOR FIXED FILM 230 ohms 1 1 2 watt 18537 97 R34 RESISTOR FIXED COMPOSITION 150 K ohms 5 1 2 watt 18414 151 R35 R36 RESISTOR FIXED COMPOSITION 120 K Ohms 5 1 2 watt 18414 121 R37 RESISTOR FIXED FILM 500 ohms 1 1 2 watt 18537 58 R38 RESISTOR SPOOL 60 ohms 18684 113 14 REF HICKOK DESIG NAME AND DESCRIPTION PART NO R39 R40 RESISTOR SPOOL 40 ohms 18684 111 R4 Same as R38 R42 Same as R37 R43 RESISTOR SPOOL 198 ohms 8684 119 R44 RESISTOR SPOOL 2 ohms 8684 102 R45 RESISTOR VARIABLE 250 K ohms 6925 259 R46 RESISTOR FIXED COMPOSITION megohm 10 1 2 watt 8415 102 R47 RESISTOR FIXED COMPOSITION 36 K ohms 5 1 2 watt 8413 361 R48 RESISTOR FIXED FILM 330 K ohms 1 1 2 watt 8537 100 R49 RESISTOR FIXED FILM 40 K ohms 1 1 2 watt 8537 94 R50 RESISTOR FIXED FILM 9900 ohms 196
7. E E14980 W43357 W45788 3613 3334 3334 3613 8593 8598 8601 8664 3CR241 3ER248 B9M15822 B9M16067 B9M16275 B9M16534 B9M17571 9 18941 17A470303 17A485459 TBR102D TBR104D TBR103D 397021 397022 397023 397036 407100 408100 SW407300 571606 First Selector H mmm mm o QO mum emnugGtmuomu euoumomosmmodumsimssm Neon Lamp Should Light in these positions c lt lt lt lt lt lt lt lt lt lt lt 13 PARTS LIST Reference designations have been assigned to identify all parts used in this instrument An asterisk designates a part which should be replaced by authorized Hickok repair stations or factories It is therefore recommended that the entire instrument be returned for repair if trouble exists with such a part In ordering parts refer to the current parts price list for this instrument Prices are subject to change without notice and the minimum billing charge is REF HICKOCK DESIG NAME AND DESCRIPTION PART NO Cl CAPACITOR FIXED ELECTROLYTIC 8 uf 350 volts 3085 68 C2 C3 CAPACITOR FIXED PLASTIC COATED 05 uf 400 volts 3105 175 C4 CAPACITOR FIXED ELECTROLYTIC 100 uf 6 volts 3085 40 5 CAPACITOR FIXED MICA 470 pf 1096 500 volts 3095 8 C6 CAPACITOR FIXED CERAMIC 005 uf 0 100 disc type 8110 7 C7 CAPACITOR FIXED MICA 2700 pf 10 1000 volts 3095 268 DS1 ILAMP
8. E isolates tube elements successively from all other elements and registers the leakage in megohms between the chosen element and all others connected in parallel Forty volts d c is applied in this test The significance of the lettered positions of the short switch is as follows HEATER isolated from other elements B GRID isolated from other elements C SCREEN isolated from other elements D PLATE isolated from other elements E SUPPRESSOR isolated from other elements NOTE Position A includes heater cathode leakage In tubes having filamentary cathodes the heater and cathode are identical therefore the meter will normally indicate near the zero mark on position A of the shorts switch Gas Test The push switches P5 Gas 1 and P6 Gas 2 are used to test amplifier tubes for gas content a Make Micromho test in the ordinary way b Setthe Bias Voltmeter switch to the 50 volt range and the Function switch to posi tion D Hold down P5 and adjust the Bias control to bring the meter reading down to 500 on the 3000 scale c Hold down P5 and press P6 Because of a charging capacitor the meter will de flect either up scale or down scale about one division after P6 is pressed and will settle to a new reading An upscale reading after settling is the result of grid current due to gas or grid emission sometimes referred to as poisoned grid If the upward movement is not more than one large division two small divisions the ga
9. M42H M42HG KX42C 14251 49A 49AJ K49AJ KX49A 49 1 49A2 49B2 K49B L498 M49B BM49B K49C SSeS m M49C BM49C BK49C K49E L49E K49D BK49D L49D L49F M49H M49HG KZ49B KZ49C K49BJ L49BJ L4982 49AJ K49AJ KX49B LX49B LX49C L49DJ L49S3 50A2 a ala ala ala 50A2MG 50B2 50X3 K52H M52H K54B 55A K55A 55A KX55A 55B K55B M55B BM55B L55BG LX55B 55A2 55B2 K55C L55C OL SS ooo 11 TUBE TYPE KX55C K55CP K55D L55D 155 55 155 55 155 K55H M55H M55HG L55S1 L5582 60R30G 64 23 67 K67B L67B L73B K74B L74B KX74C 80A K79B K80B K 80C L80B KX80B K80F KX87B LX87B L90B K90F M90F K92F M92F 92A L92B 95K2 L99D 10088 1208 12088 135K1 135K1A 140L4 140L8 140R4 140R8 140R 140L44 140R44 165L4 165R4 165R8 165R 165L44 165R44 185L4 185L8 185R4 185R8 185R 185144 185 44 200 250 250 8 290LA 300 4 320 4 340 808 1 First Selector E m Tr Uj Cd Uj tri tC Cj Cj Cd m mj Cd mi CsI cs m m m m m mm mm m Om z m O m m mm m m m m ADA AAD Neon Lamp Should Light Haas H nn Haas dd AH dd in these Positions V lt lt lt lt 2 TUBE TYP
10. RANSFORMER filament 20800 300 TRANSFORMER plate 20800 301 BOOKLET instructions 2490 581 15 d wm M RES d pe E
11. alue of the resistor inserted between the self bias posts mentioned above and also upon the plate current flowing Tube handbooks can be used as a guide to the value of the self bias resistance to use When completing the self bias test reconnect the two binding posts by the normal short ing bar and throw the toggle switch back to the NORMAL position Plate Current In the upper center of the control panel are two posts designated PLATE CURRENT These posts are normally shorted by an attached bar A suitable low resistance D C milliammeter connected across these posts will measure the plate current flowing through the tube being tested Connect the positive terminal of the meter to the positive binding post NOTE A D C milliammeter connected into the SELF BIAS circuit will measure the total cathode current In measuring rectifier tube current the meter reading must be multiplied by two because rectifier tubes conduct only during a positive half cycle whereas the meter integrates over a complete cycle In checking thyratrons such as the 884 and 885 the bias voltmeter should be set initially at its highest negative value about 40 volts The designated button is held down while the bias voltage is gradually reduced until the tube strikes that is begins to con duct which is indicated by a sudden deflection of the meter The chart indicates the ap proximate voltage at which the tube strikes There may be a small variation above or be
12. ate jack 15 connected to the positive pole of the capacitor NORMAL LOW Plate Volts In the NOTATIONS column of the data chart for some tubes will be found PLATE VOLTS LOW This notation indicates that the PLATE VOLTS switch located just above the FUNCTION switch is to be set on the LOW position Return the switch to NORMAL for all other tubes Heater Current In the lower right hand corner of the panel will be found two binding posts which are normally connected together by a jumper By removing this jumper and connecting a suitable Milliammeter or Ammeter between these two binding posts the indicating instrument will read the current being drawn by the heaters of the tube under test The actual voltage at the tube under test will be the voltage as indicated by the filament selector switch minus the voltage drop across the indicating Milliammeter or Ammeter This voltage will generally be of a very low magnitude but can be calculated by multiplying the current normally drawn by the tube under test by the impedance of the meter connected in series with this tube or it can be actually measured with a sensitive AC Voltmeter If the impedance of the meter is much more than 0 2 ohms the voltage drop might be appreciable percentage wise to the voltage delivered to the tube For example if the current at the tube is normally 0 6 amperes and the impedance of the current measuring instrument were 0 5 ohms the resultant loss would be the product o
13. ce station in your locality 19120 153 OPERATING INSTRUCTIONS FOR MODEL 539C TRANSCONDUCTANCE TUBE TESTER FOREWORD The Model 539C Mutual Conductance Transconductance Tube Tester is designed for use by technicians engineers and others who demand an instrument of the very highest quality for rapid and accurate testing of vacuum tubes Like all Hickok Tube Testers it is based upon the well known formula for mutual conductance Aip 06 Aeg where ip is the plate current change eg is the grid voltage change and Gm is the Mutual Conductance Transconductance Mutual Conductance and Transconductance are used interchangeably This instrument is equipped with three meters all made in our own plant and calibrated with great accuracy a sensitive Transconductance meter measuring micromhos in six ranges up to 60 000 micromhos This meter also has a scale reading to 200 volts for V R tube testing and a scale reading to 50 megohms for leakage testing b An A C voltmeter which insures standardized voltages to the tube s base and c two range 0 10 0 50 D C voltmeter to accurately adjust the negative bias on tube s control grid Also a scale to 100 M A d c for V R milliamperes Voltage adjustments are made while the tube being tested is delivering its rated load NOTE Always check a tube for shorts before proceeding with Mutual Conductance test OPERATING INSTRUCTIONS Read these instructions through b
14. d SUPPRESSOR in that order In the example given above the heater terminals are connected to pins 8 and 1 The GRID is connected to pin 6 PLATE to pin 2 SCREEN to pin 3 CATHODE to pin 7 and SUPPRESSOR to pin 5 These switches are electrically interlocked in such a way that it is impossible to connect two different voltage elements to the same pin Thus accidental shorts are avoided Short Test In the Model 539C Hickok has introduced an entirely new concept in short and leakage testing In addition to the conventional neon lamp short indication there is a d c leakage test which registers up to 50 megohms on the scale of the large Gm meter Neon Lamp Short Teat Turning the SHORTS switch successively through the positions 1 2 3 4 5 connects the various pairs of elements in turn across the test voltage Tubes having shorted elements will complete the circuit and cause the neon SHORT lamp to glow Tubes may be tested for shorts either hot or cold Normal sensitivity of the neon lamp is about 1 3 Megohm A short is indicated by a steady glow of the neon lamp in certain positions of the SHORTS switch A shorted tube should be discarded without further test An improved neon Short Test is incorporated in the design of this tube tester Wide experience has demonstrated that most satisfactory results are obtained when tubes are classified for short test purposes The toggle switch is thrown to miniature and subminiature position for all subminia
15. efore attempting to operate the tester 1 There are two rectifier tubes an 83 and a 5Y3GT necessary to operate this tester They are included The Short Lamp is a 1 25 watt 110 volt miniature bayonet base neon signal lamp This lamp will last indefinitely unless broken The Fuse Lamp is a standard No 81 single contact auto bulb This can be procured from any auto dealer or gasoline station attendant This fuse lamp is in the primary circuit of the transformer FUNCTIONS OF THE VARIOUS CONTROLS The line adjustment control rheostat in the 539C Tester is connected with a small A C voltmeter as a constant calibration indicator which is normally always in circuit The small A C voltmeter may also be used to register 60 cycles A C line voltage fed to the set by operating the test button P7 designated LINE TEST in the lower right part of the control panel Readjust after pressing the P4 Test Button Selectors The row of seven selector switches across the center of the control panel is for the purpose of conducting proper voltages to the tube s base pins On the roll data chart below the word Selectors appear the switch settings Example JR 6237 5 Starting at the left the first switch is set at J the second switch at R the third at 6 the fourth 2 the fifth 3 the sixth 7 and the seventh 5 The first two switches control the filament or heater connections The other switches control the GRID PLATE SCREEN CATHODE an
16. en testing ordinary rectifier tubes such as the 5Y3 This switch applies a medium voltage which is best adapted to reveal defects in this type of tube Good tubes will read above the mark RECTIFIERS and DIODES O K In the chart column headed SHUNT are listed the numbers to which the SHUNT dial is to be set when testing Rectifiers and Diodes E 11 12 13 14 Socket Numbering Sockets are wired according to EIA numbering and the numerical values of the lettered dials are as follows Selector Positions Socket Connections No Connection Bue 1 Cra ire 7 2 Docs less 3 E wd uid 4 F ub PP 5 G W 6 6 EE se ave 7 J Me y eq s 8 Z RP 9 10 2 vod vou OX 11 3 D OT 4 12 4 No Connection Meter Reverse Directly below the indicating meter is a switch marked REVERSE NORMAL With certain tubes such as the 117N7 the meter when set on NORMAL will deflect backwards to the left when push switch P3 is pressed for rectifier test In such case turn the meter switch to REVERSE which will cause the pointer to move up the scale After this test has been made return the switch to NORMAL Top Caps There are two jacks in the upper center of the control panel marked GRID and PLATE These are used when making connection to the top cap of the tube being tested On the data chart in the NOTATIONS column opposite tube types having top caps is the notation CAP G or CAP P G
17. f these two or 0 3 of one volt Pilot Lamp Testing The center of the large 7 pin socket is used to check pilot lamps Set the filament selector switches on HR Set the filament voltage switch to the proper voltage for the lamp being tested 9 Tomo CA Turn Tester on Set filament switch to BLST Set SHORT TEST switch on 5 selectors on zero TO TEST BALLAST TUBES Set first selector switch to letter shown in column marked first selector switch Set all numbered ROTATE second selector switch NEON LAMP SHOULD LIGHT IN POSITIONS NOTED TUBE TYPE 1A1 1B1 1C1 1E1 1F1 1G1 1J1 1K1 1V1 1Y1 1Z1 1L1 1N1 1P1 1Q1 1R1G 1S1G 1T1G 1U1G 2 2UR224 2LR212 3 03G 4 5 6 133 6 6AA 7 8 9 10A 10AG 10AB K17B M17C BM17C M17HG M17H K23B K23C KX23B KX30C M30H First Selector Neon Lamp Should Light 44 in these positions K30D 33A 33AG K34B 36A K36B BK36B L36B L36C KX36Z KX36C 36D L36D L36DJ K36H M36H M36HG 40A1 14051 14052 42A m m m Om m m m m m mim mimi m Sm m m Sm m m m m m m m m m m m w 44 10 TUBE TYPE First Selector Neon Lamp Should Light in these positions 42 1 J U 42A2 42B2 U K42B L42B M42B KX42B LX42B L42BX K42C L42C M42C BK42D K42D L42D LX42D L42DX K42E L42E 3 L42F 42HA 42HJ
18. here matched tubes are essential Life Test The Model 539C DYNAMIC MUTUAL CONDUCTANCE TUBE TES TER is equipped with a special feature to enable Life Test to be made on the tube In the center of the control panel is a switch designated CATH ACT NORM and TEST While holding everything else at normal this switch reduces the filament voltage by 109 a Measure the mutual conductance in the ordinary way with switch set on NOR MAL b Throw the CATH ACT switch to TEST position The mutual conductance should not drop more than 20 c After making life test return the switch to NORMAL for all other tests In testing 35Z5 and 4575 rectifier tubes it is advisable to turn the power off for about 15 seconds after throwing the CATH ACT switch to TEST to allow the cathode to cool Then turn the power on and note new reading of the meter Self Bias Provision is made to test tubes under self bias condition In the up per edge of the control panel are two binding posts designated SELF BIAS These posts are normally shorted by an attached bar To use SELF BIAS connect a suitable bias re sistor together with an electrolytic capacitor of 2000 Ofd in parallel across these binding posts The positive terminal of the capacitor should be connected to the positive binding post The toggle switch in the upper left of the control panel is thrown from NORMAL po sition to the SELF BIAS position The bias volts under self bias condition depends upon the v
19. leak If the switch 15 turned from position 1 one to position 2 two a sharp flash of the neon lamp will be seen This will not repeat until the switch is again turned to position 1 one allowing the condenser to recharge through the leakage Many baffling cases of trouble can be located in this way It has been established that heater cathode leakage as high as 30 megohms will cause noise in repeater circuits in television service on coaxial lines Noise Test The short test circuit is also used in making noise tests on vacuum tubes Connections are made from the noise test jacks to the antenna and ground posts of any radio receiver The tube under test is tapped with the finger as the SHORTS switch is turned through positions 1 2 3 4 5 Intermittent disturbances which are too brief to register on the neon lamp will be reproduced by the loud speaker as static Leakage Test on Meter An added feature in the Model 539C is its ability to measure element leakage up to 50 megohms on the dial of the large Gm meter The research EN engineer and technician will find this feature a great aid in routine investigations Ta Every engineer knows that in certain tube applications leakage is more significant than in others The metered leakage feature of the Model 5390 will enable him to form sound judgment as to the leakage to be tolerated in different applications Operating Leakage Test Turning the SHORTS switch through positions A B C D
20. s Turn V R volts knob fully counter clockwise Turn power adjust knob fully clockwise Press PA LOCK Place V R tube in proper socket and turn power ON Turn V R voltage control knob slowly clockwise The large Gm meter should start to read d c volts on the 0 200 volt scale Example In the notations column for the 0A3 tube appears Starts at about 100 Volts Regulation 5 volts from 5 to 40 ma In the column marked MIN MUT COND is the nominal operating voltage for this tube 75V When the V R tube strikes as explained in j above the voltmeter reading will drop back to operating voltage The V R current is read on the 0 100 m a range of the bias meter 8 20 2 22 23 l For the example adjust the m a current from 5 to 40 milliamperes by turning the V R volts and mils knob The 0A3 tube should not exhibit a voltage change of more than 5 volts m When completing a V R tube test unlock P4 push button Ohmmeter Feature The Model 539C tube tester can be used as a utility ohmmeter as follows a Setthe SHORTS switch on position B b Connect two prod leads into the grid and plate jacks in the center of the control panel The red plate jack will be the positive lead c Touch together the two prods and adjust the ohmmeter pointer to zero Resistance up to 50 megohms can be read directly on the megohm range d Hlectrolytic capacitors can be checked for leakage Observe that the red pl
21. s content is satisfactory Some tubes develop gas after being heater for a period of time If a tube 15 sus pected allow it to heat for a few minutes This constitutes a very sensitive gas test Gas content on the order of 0 1 microampere can be detected Gas content is a very important factor in modern receivers of all types con taining AVC and AFC circuits as the presence of gas causes the grid to become conductive and as changes in grid bias operate through resistors of comparatively high value correct functioning cannot be obtained with a gassy tube The presence of gas results in actually changing the grid bias Gas is especially harmful in television rubes Dynamic Transconductance The Push Switch P4 is mechanically divided into two sections non locking and locking Both sections perform identical electrical functions If momentary contact is needed press the non locking button If extensive tests are to be made use the locking button The locking button is released by pressing the non locking button 4 The indicating meter will register the tube s value in eight ranges 60 000 gmho at 25 Volt signal B 30 000 pmho at 25 Volt signal C 15 000 umbho at 25 Volt signal D 6 000 pmho at 5 Volt signal E 3 000 pmho at 2 5 Volt signal F 600 umho at 1 Volt signal G Rectifiers and Diodes no signal H Voltage Regulator tubes The 600 micromho range was designed especially to test subminiature tubes Low plate and
22. screen volts are automatically applied when FUNCTION switch is set on position F The FUNCTION switch automatically changes the signal volts when the appropriate setting is made The chart setting for the tube to be tested will indicate where the FUNCTION switch should be set such as A B C Gor H in the column preceding Micromhos The Micromho values printed on the data roll are minimum values Good tubes will read above these values In the column headed BIAS VOLTS is listed the exact voltage to which the BIAS VOLTS meter is to be set when testing a tube Make final bias adjustment after the P4 button is pressed Certain pentode tubes such as the 3A4 are tested with reduced screen voltage This is accomplished by holding down P1 and pressing P4 Specific instructions are printed in the NOTATIONS column for each tube requiring reduced screen voltage 10 Rectifier Test The push switches P1 P2 and P3 are used to test various types of rectifier elements a push switch PI is used when testing detector diodes It applies a low voltage which will not injure the delicate cathode Good diodes will cause the meter pointer to read above mark RECTIFIERS and DIODES O K b Push switch P2 is used when testing cold cathode rectifiers such as the OZ4 This applies a voltage sufficiently high to ionize the tube and start conduction Good tubes will read above the mark RECTIFIERS and DIODES O K c Push switch is used wh
23. ture button seven pin and button nine pin tubes The other position 15 used for rubes having regular base pins including loktal base tubes Locating Shorted Elements by Neon Lamp In the following table X under any position indicates that the neon lamp glows in that position 2 6a 6b KIND OF SHORT 1 2 3 4 5 HEATER CATHODE HEATER GRID HEATER SCREEN HEATER PLATE gt lt gt lt HEATER SUPPRESSOR gt lt gt lt gt lt CATHODE GRID CATHODE SCREEN CATHODE PLATE CATHODE SUPPRESSOR gt lt gt GRID SCREEN GRID PLATE gt GRID SUPPRESSOR SCREEN PLATE x SCREEN SUPPRESSOR X PLATE SUPPRESSOR X Heater Cathode Leakage A particularly troublesome defect in tubes especially those used in television is a leakage between heater and cathode This leakage may be quite high sometimes running to several megohms It may be too high to cause the neon lamp to glow in the ordinary way However these leaks may be detected on your new 539C You will note that a heater cathode short will cause the neon lamp to glow on position 1 one While the short switch is resting on position 1 one during short test operation a condenser will be charging through the
Download Pdf Manuals
Related Search