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Wavetek 39A Maintenance Manual

Manual is about: 40MHz Arbitrary Waveform Generator

Summary of 39A

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    Maintenance manual model 39a 40mhz arbitrary waveform generator october 2005 - issue 1 this document contains information proprietary to wavetek and is provided solely for instrument operation and maintenance. The information in this document may not be duplicated in any manner without the prior app...

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    Table of contents specifications 2 safety 10 installation 11 general 12 circuit descriptions 13 calibration 18 parts list 21 component layouts 29 circuit diagrams 31 1.

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    Specifications note: this specification covers the whole series which includes 2- and 4- channel instruments; the interchannel specifications only apply to the multi-channel instruments. Specifications apply at 18 −28ºc after 30 minutes warm−up, at maximum output into 50Ω waveforms standard waveform...

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    Pulse and pulse train output level: 2.5mv to 10vp −p into 50Ω rise and fall times: period: range: 100ns to 100s resolution: 4-digit accuracy: ±1 digit of setting delay: range: −99.99s to +99.99s resolution: 0.002% of period or 25ns, whichever is greater width: range: 25ns to 99.99s resolution: 0.002...

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    Operating modes triggered burst each active edge of the trigger signal will produce one burst of the waveform. Carrier waveforms: all standard and arbitrary maximum carrier frequency: the smaller of 1mhz or the maximum for the selected waveform. 40msamples/s for arb and sequence. Number of cycles: 1...

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    Tone switching capability provided for both standard and arbitrary waveforms. Arbitrary waveforms are expanded or condensed to exactly 4096 points and dds techniques are used to allow instantaneous frequency switching. Carrier waveforms: all waveforms except pulse, pulse train and sequence. Frequenc...

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    Sync out - one for each channel multifunction output user definable or automatically selected to be any of the following: waveform sync: (all waveforms) a square wave with 50% duty cycle at the main waveform frequency, or a pulse coincident with the first few points of an arbitrary waveform. Positio...

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    Hold holds an arbitrary waveform at its current position. A ttl low level or switch closure causes the waveform to stop at the current position and wait until a ttl high level or switch opening which allows the waveform to continue. The front panel man hold key or remote command may also be used to ...

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    Inter-channel analog summing: waveform summing sums the waveform from any channel into the next channel. Alternatively any number of channels may be summed with the signal at the sum input socket. Carrier frequency: entire range for selected waveform. Carrier waveforms: all standard and arbitrary wa...

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    General display: 20 character x 4 row alphanumeric lcd. Data entry: keyboard selection of mode, waveform etc.; value entry direct by numeric keys or by rotary control. Stored settings: up to 9 complete instrument set −ups may be stored and recalled from battery −backed memory. Up to 100 arbitrary wa...

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    Safety this generator is a safety class i instrument according to iec classification and has been designed to meet the requirements of en61010 −1 (safety requirements for electrical equipment for measurement, control and laboratory use). It is an installation category ii instrument intended for oper...

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    Installation mains operating voltage check that the instrument operating voltage marked on the rear panel is suitable for the local supply. Should it be necessary to change the operating voltage, proceed as follows: 1) disconnect the instrument from all voltage sources. 2) remove the screws which re...

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    General service handling precautions service work or calibration should only be carried out by skilled engineers. Please note the following points before commencing work. Most of the integrated circuits are cmos devices and care should be taken when handling to avoid damage by static discharge. Also...

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    Circuit descriptions general the following sections should be read with reference to the block diagram and the circuit diagrams. Common remote control gpib/ rs232 common cpu int trig dc offset sum out control dac,s waveform fpga sync out trig out from next channel trig out from previous channel comm...

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    Clock synthesis mode in clock synthesis mode the addresses are always sequential (an increment of one) and the clock rate is adjusted by the user in the range 40mhz to 0.1hz. The frequency of the waveform is clock frequency ÷ waveform length, thus allowing short waveforms to be played out at higher ...

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    Mpu and memory the majority of the digital hardware in the instrument is contained in 3 lsi devices, these being a microprocessor unit, ic3, and 2 field programmable gate arrays, ic10 and ic221. The z80180 mpu contains an 8 bit z80 core, 2x16 bit counter-timers, 2x8 bit serial interfaces and a memor...

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    Trigger generator this is created by a counter-timer in ic10. The counter-timer produces a squarewave in the range 100khz to 0.005hz. The fpga, ic221, may be set to use this as the internal trigger. Power supply the transformer has two separate secondaries; one provides ± 15v by ic30 and ic31, the o...

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    Zero crossing detector ic201 is a comparator with positive feedback via r203. M is the signal selected by ic211 and m2 is the signals dc mid-point which is buffered by ic200-b. This circuit is used to detect zero crossing of high frequency dds waveforms of sine, ramp or triangle and sent to the fpga...

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    Calibration all parameters can be calibrated without opening the case, i.E. The generator offers ‘closed −box’ calibration. All adjustments are made digitally with calibration constants stored in eeprom. The calibration routine requires only a dvm and a frequency counter and takes no more than a few...

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    When the correct password has been entered from the keyboard the display changes to the opening screen of the calibration routine and calibration can proceed as described in the calibration routine section. If an incorrect password is entered the message incorrect password! Is shown for two seconds ...

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    Vco adjustment this should not normally be necessary and l6 is sealed at the factory. However if a problem is suspected or components in this circuit have been changed carry out the following test first. Set the output to 10mhz squarewave and check that the voltage at tp200.3 is −9.5v to −10.5v. Che...

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    Parts list pcb assy - keyboard (44912-0710) part number description position 22224-0010 encoder rot 36 pos w/o detent sw1 22226-0101 keyswitch - alps skhhbw k5-12, 20, 21, 30, 31, 48 22226-0150 keyswitch light grey k1, 2, 4, 13-19, 22-29, 32-47, 49 23202-1680 res 680rf w25 mf 50ppm r1-3,5,11,12 2338...

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    Pcb assy – main (44912-0720) continued/... Part number description position 22573-0070 header 4way str sil std tp200 22573-0202 header 2 way straight .156p pj3, 7, 200 22573-0204 header 4 way straight .156p pj11/12, pj13 22573-0206 header 6 way straight .156p pj8 22574-0450 skt 9w r/a d-type (clip i...

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    Pcb assy – main (44912-0720) continued/... Part number description position 23105-2300 res sm0805 3k00f w1 r30, 310 23105-2470 res sm0805 4k70f w1 r23, 282, 288, 289, 290, 295, 296, 298 23105-2510 res sm0805 5k10f w1 r233, 242, 306 23105-2560 res sm0805 5k60f w1 r240, 270 23105-3100 res sm0805 10k0f...

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    Pcb assy – main (44912-0720) continued/... Part number description position 23428-0560 cap56pg 100v cer n150 p2.5 c239, 247 23428-1100 cap 100pg 100v cer npo p2.5 c12, 235, 241, 249 23428-1150 cap 150pg 100v cer n150 p2.5 c236 23428-1180 cap 180pg 100v cer n750 p2.5 c238, 243 23461-0015 cap sm0805 1...

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    Pcb assy – main (44912-0720) continued/... Part number description position 27106-0633 ic el2099ct ic220 27106-1110 ic sm lm358m dual op amp ic16, 200 27106-1160 ic sm lm324m op amp ic209 27106-1170 ic sm ad8055ar op amp ic219 27106-1180 ic sm ad8056ar op amp ic25, 216 27106-1210 ic sm lmc662cm ic29...

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    Pcb assy – main (44912-0720) continued/... Part number description position 28151-0010 buzzer buzz 28502-0020 resonator ceramic 12mhz xtl1 28515-0070 osc module 10mhz vcxo ic105 31331-9030 screen pcb mount s205, 206 35555-3210 pcb - main front panel assy part number description position 20030-0263 w...

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    Rear panel assy part number description position 20037-0401 solder tag shakeproof - 4ba earth 20038-9502 washer m4 spring earth 20063-0010 screw no6 x 3/8 nib hdpz st/ab transformer 20210-0102 nut m4 zpst earth 20213-0040 captive nut spire no.6 20223-9001 screw m3 x 8 raised ckhdpz mains inlet 20236...

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    Casing and other items continued/... Part number description position 22491-0120 mains ld 2m st iec/uk plug 5a uk versions 22491-0270 mains ld 2m st iec/euro plug euro versions 22491-0040 mains ld 2m st iec/usa pl usa versions 22469-0203 solder terminal pin (18-0223k) display cable 22575-0202 skt2w ...

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    Component layouts main pcb 29.

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    Keyboard pcb gpib pcb 30

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    Circuit diagrams 31.

  • Page 33

    Gpib interface pcb.

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    Keyboard pcb.

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    Main pcb sheet 1 of 4 mpu and interfaces.

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    Main pcb sheet 2 of 4 analogue section.

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    Main pcb sheet 3 of 4 waveform fpga and memory.

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    Main pcb sheet 4 of 4 power supplies.