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Multiplexing Basics

 

2-8

 

2.4

Multiplexer expansion

 

With the use of additional switching cards and mainframes,
larger systems can be configured. Each Model 7001 Switch
System mainframe will accommodate up to two cards, and
the Model 7002 Switch System mainframe can accommo-
date up to 10 cards.

 

2.4.1 Multi-card switching systems 

 

Separate switching systems

 

Multiple single-card systems can be configured by removing
the backplane jumpers from each additional card. All cards
will be controlled by the same mainframe, but they will be
electrically isolated from each other. Figure 2-10 shows an
example using two Model 7015 multiplexer cards.

 

Multiplexer input expansion 

 

You can double the number of multiplexer inputs by simply
installing two “as shipped” Model 7015s in the Model 7001
mainframe. Similarly, the number of multiplexer inputs can
be increased by a factor of 10 by installing 10, “as shipped”
Model 7015s in a Model 7002. By leaving the backplane

jumpers installed, the banks of the multiplexer card installed
in slot 1 (CARD 1) are automatically connected to the banks
of the multiplexer card installed in slot 2 (CARD 2) through
the analog backplane (and with any remaining cards installed
in a Model 7002).

Figure 2-11 shows an example of input expansion. Each
Model 7015 card is configured as four 1 

 

×

 

 10 multiplexers.

By connecting the banks together (via Model 7001/7002 an-
alog backplane), the resulting multiplexer system has 20 2-
pole inputs for each of the four banks. Note that, if all the
bank-to-bank jumpers on any card are installed (as shipped),
the result would be a single 1 

 

×

 

 80 multiplexer. A total of 10

Model 7015 cards installed in a Model 7002 would yield a
single 1 

 

×

 

 400 multiplexer with all bank-to-bank jumpers in-

stalled.

 

NOTE

 

Connecting any two banks on one card to-
gether also connects the corresponding
banks of the backplane together. Thus, the
corresponding banks of other card(s) will
be connected together even if the bank-to-
bank jumpers on those cards are not in-
stalled.

Figure 2-10

Two separate multiplexer systems

1

10

Bank B

Bank C

Bank D

Bank A

7015

1

10

1

10

1

10

7001/7002

Analog

Backplane

Card 1

Four 1x10 Multiplexers

7015

1

10

1

10

1

10

1

10

Card 2

Backplane

Jumpers

Removed

Four 1x10 Multiplexers

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Summary of Contents for 7015-C

Page 1: ...service in house repair center WE BUY USED EQUIPMENT Sell your excess underutilized and idle used equipment We also offer credit for buy backs and trade ins www artisantg com WeBuyEquipment REMOTE IN...

Page 2: ...tains Operating and Servicing Information Models 7015 S and 7015 C 40 Channel Solid State Multiplexer Cards 7015 901 01 Rev A 6 93 Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SO...

Page 3: ...E AND EXCLUSIVE REMEDIES NEITHER KEITHLEY INSTRUMENTS INC NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INS...

Page 4: ...ion Manual 1993 Keithley Instruments Inc All Rights Reserved Cleveland Ohio U S A First Printing June 1993 Document Number 7015 901 01 Rev A Artisan Technology Group Quality Instrumentation Guaranteed...

Page 5: ...e numbered sequentially When a new Revision is created all Addenda associated with the previous Revision of the manual are incorporated into the new Revision of the manual Each new Revi sion includes...

Page 6: ...hazardous voltage is present in any unknown circuit before measuring Users of this product must be protected from electric shock at all times The responsible body must ensure that users are prevented...

Page 7: ...e CAUTION heading in a manual explains hazards that could damage the instrument Such damage may invalidate the warranty Instrumentation and accessories shall not be connected to humans Before performi...

Page 8: ...sis CONTACT TYPE Solid state switch CHANNEL RESISTANCE per conductor 210 CONTACT POTENTIAL 7015 C 5 V per channel contact pair 7015 S 4 V per channel contact pair OFFSET CURRENT 1nA ACTUATION TIME 500...

Page 9: ...ipment 1 3 1 8 Optional accessories 1 3 2 Mutliplexing Basics 2 1 Introduction 2 1 2 2 Basic multiplexer configurations 2 1 2 2 1 Multiplexer bank to bank jumpers 2 2 2 2 2 Backplane jumpers 2 5 2 3 T...

Page 10: ...Resistor testing 4 7 4 4 4 Testing with matrix cards 4 10 4 4 3 Transistor current gain testing 4 10 4 5 Measurement considerations 4 12 4 5 1 Thermoelectric potentials 4 12 4 5 2 Channel resistance 4...

Page 11: ...5 5 6 Troubleshooting 5 16 5 6 1 Troubleshooting equipment 5 16 5 6 2 Troubleshooting access 5 16 5 6 3 Troubleshooting Procedure 5 16 6 Replaceable Parts 6 1 Introduction 6 1 6 2 Parts lists 6 1 6 3...

Page 12: ...mper installation 3 3 Figure 3 4 Backplane jumpers 3 4 Figure 3 5 Model 7015 screw terminal connector card 3 4 Figure 3 6 Typical screw terminal connections 3 5 Figure 3 7 Cable clamp for screw termin...

Page 13: ...ion by path isolation resistance 4 14 Figure 4 13 Power line ground loops 4 15 Figure 4 14 Eliminating ground loops 4 16 5 Service Information Figure 5 1 Path resistance test connections 5 4 Figure 5...

Page 14: ...e 4 7 Paired Channels in 4 pole Operation 4 7 5 Service Information Table 5 2 Verification equipment 5 2 Table 5 8 Bank isolation test summary 5 8 Table 5 9 Channel to channel isolation test summary 5...

Page 15: ...The rest of Section 1 is arranged in the following manner 1 2 Features 1 3 Warranty information 1 4 Manual addenda 1 5 Safety symbols and terms 1 6 Specifications 1 7 Unpacking and inspection 1 8 Rep...

Page 16: ...front of this man ual These specifications are exclusive of the multiplexer mainframe specifications 1 7 Unpacking and inspection 1 7 1 Inspection for damage The Model 7015 is packaged in a re sealabl...

Page 17: ...he wiring con figuration of the first connector card Model 7011 KIT R This connection kit includes a 96 pin female DIN connector that will mate directly to the connec tor on the Model 7015 C or to a s...

Page 18: ...g differential floating switching and sensing 2 4 System expansion Discusses the various configura tions that are possible by using multiple cards 2 2 Basic multiplexer configurations A simplified sch...

Page 19: ...A 7015 1 10 1 10 1 10 HI LO Input 1 of 40 HI LO Bank HI LO Jumpers HI LO C D HI LO HI LO Bank to Bank Jumpers Backplane Jumpers to 7001 7002 Analog Backplane Note Factory Configuration shown Four 1 1...

Page 20: ...B 2 1 10 2 2 Bank C 2 1 10 2 2 Bank D 2 Output B Output C Output D Figure 2 3 Two 1 20 multiplexer configuration jumpers installed Output A 1 10 2 2 Bank A Inputs 2 1 10 2 2 Bank B 2 1 10 2 2 Bank C...

Page 21: ...plexer configuration jumpers installed Output A 1 10 2 2 Bank A Inputs 2 1 10 2 2 Bank B 2 1 10 2 2 Bank C 2 1 10 2 2 Bank D 2 2 2 2 Jumpers Jumpers Jumpers Artisan Technology Group Quality Instrument...

Page 22: ...d 1 Card 2 Model 7001 7002 H L G Row 1 or Bank A H L G H L G Row 2 or Bank B H L G H L G Row 3 or Bank C H L G H L G Row 4 or Bank D H L G H High L Low G Guard Row Matrix Card 7012 Bank MUX Card 7015...

Page 23: ...configurations to help minimize noise pickup in sensitive measurement applications These shields are shown connected to chassis ground For some test configurations shielding may prove to be more effe...

Page 24: ...ntial switching example HI LO Source or Measure 7015 H L H L DUT Bank A B Input 1 10 Out In Bank C D Input 1 10 Out In Figure 2 9 Sensing example Source HI Sense HI Sense LO Source LO Source or Measur...

Page 25: ...the banks of the multiplexer card installed in slot 2 CARD 2 through the analog backplane and with any remaining cards installed in a Model 7002 Figure 2 11 shows an example of input expansion Each M...

Page 26: ...10 1 10 7001 7002 Analog Backplane Card 1 Quad 1x10 Multiplexers 7015 1 10 1 10 1 10 1 10 Card 2 Backplane Jumpers installed Quad 1x10 Multiplexers Quad 1x20 Multiplexer multiplexer banks On the mult...

Page 27: ...Card 1 4 x 10 Matrix Notes 1 Models 7015 and 7012 backplane jumpers must be installed 2 Model 7015 bank to bank jumpers must be removed 1 10 7015 Card 2 Quad 1 x 10 Mux 1 10 1 10 1 10 Bank A Bank B B...

Page 28: ...or Model 7002 mainframe 3 2 Handling precautions To maintain high impedance isolation care should be taken when handling the relay card to avoid contamination from such foreign materials as body oils...

Page 29: ...sed to connect the LO terminals of the banks to gether The bottom terminal pairs W100 W102 and W104 are used to connect the HI terminals of the banks together Table 3 1 summarizes the purpose of each...

Page 30: ...ate the relay card from the con nector card by removing the mounting screw and pulling the two cards away from each other Remember to han dle the cards only by the edges and shields to avoid con tamin...

Page 31: ...y to the screw terminals of the twelve terminal blocks Each screw terminal will accommo date 16 22 AWG wire Figure 3 4 Backplane jumpers W100 7015 Relay Card W101 W102 W103 W104 W105 W106 W107 Backpla...

Page 32: ...amp screw enough to disengage it from the bottom half of the cable clamp B Using your thumb and forefinger press the retaining clips inward and with your other hand remove the top half of the clamp 4...

Page 33: ...HI LO 24a 23c 24 87 Input 2 HI LO 16a 15c 16 79 Input 2 HI LO 8a 7c 8 71 Input 3 HI LO 31b 31a 63 31 Input 3 HI LO 23b 23a 55 23 Input 3 HI LO 15b 15a 47 15 Input 3 HI LO 7b 7a 39 7 Input 4 HI LO 30c...

Page 34: ...e Round cable assemblies Figure 3 8 shows typical round cable connection techniques using accessories available from Keithley In Figure 3 8A connections are accomplished using a Model 7011 MTC 2 cable...

Page 35: ...Wire instrumentation and DUT to bulkhead connector See Figure 3 9 and Table 3 3 for terminal identification B 7011 MTC 2 Cut in Half Wire directly to instrumentation and DUT Multi Pin Connector Card...

Page 36: ...side of connector 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 a b c Note See Table 3 3 for terminal identification Figure 3 10 Model 7011 KIT R with cable as...

Page 37: ...plexer using the Model 7011 MTC 2 round cable assembly This cable mates direct ly to both the external bulkhead connector and the Model 7015 C multiplexer card assembly Note that the bulkhead connecto...

Page 38: ...head Connector 7011 MTR Bulkhead Connector 7011 MTC 2 Cable Assembly 84 Individual Conductors DUT Test Fixture 1 20 1 20 Instruments DUTs 1 20 1 20 1 20 1 20 Simplified Equivalent Circuit Dual 1x20 No...

Page 39: ...ument HI and LO to Banks A and B HI and LO to Banks C and D 1 20 Instruments DUTs 1 20 1 20 1 20 1 20 Simplified Equivalent Circuit Dual 1x20 Notes Bank to bank jumpers installed as follows Bank A con...

Page 40: ...ed in two Model 7001 mainframes to configure a single 1 120 multiplexer system Each card is configured as a single 1 40 multiplexer Bank to bank jumpers of all three cards must be installed to connect...

Page 41: ...MTC 2 Cable Assembly Cut in half to provide two cables Instruments DUTs 1 40 1 40 41 80 41 80 Simplified Equivalent Circuit Card 2 1x40 7001 Analog Backplane Card 1 1x40 Single 1x80 Multiplexer Notes...

Page 42: ...ruments DUTs 1 40 1 40 41 80 41 80 Simplified Equivalent Circuit Card 2 1x40 7001 Analog Backplane Card 1 1x40 Single 1x80 Multiplexer Notes 1 All bank to bank jumpers both cards must be installed 2 B...

Page 43: ...onnector Kit Cable Instruments DUTs 1 40 1 40 41 80 41 80 Simplified Equivalent Circuit Card 2 1x40 7001 Analog Backplane Card 1 1x40 Single 1x120 Multiplexer Notes 1 Backplane jumpers for both cards...

Page 44: ...both cards installed in 7001 1 must be installed 2 All bank to bank jumpers on all three cards must be installed DUT Test Fixture 81 120 Card 1 1x40 7001 1 7001 2 External Bank Connections 244 Indivi...

Page 45: ...scharged 1 Mate the connector card to the relay card if they are sep arated Install the supplied 4 40 screw at the end of the card to secure the assembly Make sure to handle the cards by the edges and...

Page 46: ...88 CHANNEL READY EXTERNAL TRIGGER O U T I N C A R D 90 250V 50 400Hz 40VA MAX LINE RATING 2 TRIGGER LINK DIGITAL I O C A R D 1 MADE IN USA Ejector Arms Open Position Tighten Ground Screw Ejector Arms...

Page 47: ...xceed the following maximum signal levels 175V peak between any two pins 34mA resistive load 0 3VA max 1 106V Hz max 4 3 Mainframe control of multiplexer card The following information pertains to the...

Page 48: ...by exclamation points Some examples of CHANNEL assignments are as follows CHANNEL 1 1 Slot 1 Channel 1 Input 1 of Bank A CHANNEL 1 40 Slot 1 Channel 40 Input 10 of Bank D CHANNEL 2 23 Slot 2 Channel 2...

Page 49: ...2 3 2 13 2 23 2 33 2 4 2 14 2 24 2 34 2 5 2 15 2 25 2 35 2 6 2 16 2 26 2 36 2 7 2 17 2 27 2 37 2 8 2 18 2 28 2 38 2 9 2 19 2 29 2 39 2 10 2 20 2 30 2 40 Examples 1 18 Slot 1 Channel 18 Input 8 Bank B...

Page 50: ...e commands are listed as follows RST TRIGger SEQuence COUNt AUTo ON ROUTe SCAN list INIT The first command resets the mainframe to a default scan configuration The second command automatically sets th...

Page 51: ...l 2 pole connection scheme shown a total of 40 DUTs per card can be tested at high scanning rates with break before make off Model 7002 only The type of measurement can vary although some sort of volt...

Page 52: ...4VAC 180 250VAC 50 60 400HZ 55VA MAX LINE FUSE SLOWBLOW 1 2A 250V IEEE 488 CHANGE IEEE ADDRESS WITH FRONT PANEL MENU OPTION SLOT 7001 Switch System 2001 Multimeter Trigger Link Cable 8501 Trigger Link...

Page 53: ...the Model 2001 is limited to the 200 range and above because the sense lead resistance is too high for the 20 range The Model 7015 can be configured for 20 channels of 4 pole operation by isolating Ba...

Page 54: ...CAL 500V PEAK F R FRONT REAR 2A 250V AMPS 350V PEAK 1100V PEAK Model 2001 Multimeter 2001 MULTIMETER 1 Dual 1x20 MUX DUTs 20 R A Test Configuration B Simplified Equivalent Circuit 20 21 40 1 20 Input...

Page 55: ...LO HI LO 220 Current Source 182 Input 220 Output R 220 Currrent Source 7015 DUT V 182 Nanovoltmeter 7015 Low level resistance measurements Many times it is necessary to make resistance measurements w...

Page 56: ...mple a 1mA collector current will result in a nominal 0 1 to 0 2V voltage drop across the relay contacts 4 4 4 Testing with matrix cards The Model 7015 can be added to a matrix switching system to enh...

Page 57: ...e 2001 Multimeter 230 Voltage Source A Test Configuration B Simplified Equivalent Circuit Amps Output Common 7015 I B NEXT DISPLAY PREV POWER DCV ACV DCI ACI 2 4 FREQ TEMP REL TRIG STORE RECALL INFO L...

Page 58: ...s that can seriously affect low level measure ment accuracy The following paragraphs discuss these ef fects and ways to minimize them 4 5 1 Thermoelectric potentials Thermoelectric potentials thermal...

Page 59: ...thermal drifts and the rel process should be repeated whenever the range is changed for best accuracy 4 5 2 Channel resistance Channel resistance is the equivalent resistance between the input and ou...

Page 60: ...nce devices The voltage measured across such a device for example can be substantially attenuated by the voltage divider action of the device source resistance and path isolation resistance as shown i...

Page 61: ...sources such as radio or TV signals or some types of electronic equipment micro processors high speed digital circuits etc or it can result from impulse sources as in the case of arcing in high volta...

Page 62: ...to avoid contamination If the connector insulators should become contaminated ei ther by inadvertent touching or from air borne deposits they can be cleaned with a cotton swab dipped in clean methano...

Page 63: ...he high impedance areas on the Model 7015 care should be taken when handling or servicing the card to prevent possible contamination The following precautions should be taken when servicing the card H...

Page 64: ...t may indicate that the multiplexer card is contaminated See paragraph 5 2 for in formation on cleaning the card 5 3 1 Environmental conditions All verification measurements should be made at an ambie...

Page 65: ...1 Turn off the Model 7001 7002 if it is on 2 Turn on the Model 2001 and allow it to warm up for one hour before making measurements 3 Connect all input terminals of Bank A together to form one common...

Page 66: ...INPUT LO INPUTS CAL 500V PEAK F R FRONT REAR 2A 250V AMPS 350V PEAK 1100V PEAK 2001 MULTIMETER Model 2001 Multimeter Measure 4 Wire Ohms A B C D 1 3 4 5 6 7 8 9 10 2 H L H L H L H L H L H L H L H L H...

Page 67: ...pathways for offset current Model 7025 Unterminated Triax Cable LO Black A Differential A B C D 1 3 4 5 6 7 8 9 10 2 H L H L H L H L H L H L H L H L H L H L H L H L H L H L Bank Outputs Model 7015 Mo...

Page 68: ...ING on the Model 182 to null out in ternal offsets Leave REL READING enabled for the entire procedure 11 Turn off the Model 7001 7002 Remove the Model 7015 from slot 1 Cut the short on B and D output...

Page 69: ...figured to test isolation between Bank A and Bank B Model 7015 5 3 7 Bank and channel to channel isolation tests Bank isolation tests check the leakage resistance between ad jacent banks Channel to ch...

Page 70: ...e card as shown in Figure 5 5 25 Install the Model 7015 in slot 1 of the Model 7001 7002 and turn on the mainframe 26 Program the Model 7001 7002 to close Channel 1 2 Bank A Input 2 Make sure all othe...

Page 71: ...and Input 4 Bank A and Input 5 Bank A and Input 6 Bank A and Input 7 Bank A and Input 8 Bank A and Input 9 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 1 10 Assumes Model 7015 installed in slot 1 of mainframe Pro...

Page 72: ...nput 10 Bank C and Input 1 Bank C and Input 2 Bank C and Input 3 Bank C and Input 4 Bank C and Input 5 Bank C and Input 6 Bank C and Input 7 Bank C and Input 8 Bank C and Input 9 1 22 1 23 1 24 1 25 1...

Page 73: ...Model 7025 Unterminated Triax Cable Red Banana to Banana Cable Ground Link Removed Unterminated Banana Cable Note Setup shown is configured to test isolation between HI and LO of Bank A 5 3 8 Differen...

Page 74: ...10 11 Bank A Bank A Input 1 Bank A Input 2 Bank A Input 3 Bank A Input 4 Bank A Input 5 Bank A Input 6 Bank A Input 7 Bank A Input 8 Bank A Input 9 Bank A Input 10 None 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1...

Page 75: ...d Link Removed Unterminated Banana Cable Source V and Measure V I A B C D 1 3 4 5 6 7 8 9 10 2 H L H L H L H L H L H L H L H L H L H L H L H L H L H L Bank Inputs Model 7015 Jumper Note Setup shown is...

Page 76: ...er up card identification information from each card is read by the mainframe This ID data includes such in formation as card ID hardware settling time and relay con figuration information ID data is...

Page 77: ...rmation into the Q out puts of the relay drivers and the appropriate relays are ener Figure 5 9 Start and stop sequences IDCLK IDDATA Start Bit Stop Bit Figure 5 10 Transmit and acknowledge sequence I...

Page 78: ...thley 7001 Control card WARNING Lethal voltages are present within the 7001 mainframe Some of the proce dures may expose you to hazardous voltages Observe standard safety pre cautions for dealing with...

Page 79: ...voltage 4 U104 pin 5 IDCLK pulses During power up only 5 U104 pin 6 IDDATA pulses During power up only 6 U100 pin 7 STROBE pulse End of relay update sequence 7 U100 pin 2 CLK pulses During relay updat...

Page 80: ...Service Information 5 18 Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 81: ...uit description if applicable 5 Keithley part number 6 4 Factory service If the card is to be returned to Keithley Instruments for repair perform the following 1 Complete the service form at the back...

Page 82: ...rd for 7015 S 7015 166 Schematic Terminal Block Board for 7015 S 7015 170 Component Layout Mass Terminated Card for 7015 C 7015 176 Schematic Mass Terminated Card for 7015 C Artisan Technology Group Q...

Page 83: ...NCE CAP 10UF 20 100 25V ALUM ELEC CAP 1UF 20 50V CERAMIC CAP 150PF 10 1000V CERAMIC DIODE SILICON IN4006 D0 41 CONN 48 PIN 3 ROWS CONNECTOR 32 PIN 2 ROWS RES 10K 5 1 4W COMPOSITION OR FILM RES 2K 5 1...

Page 84: ...sz KK Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 85: ...B2 25917 TC17 100 Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 86: ...B2 25917 Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 87: ...1006 1009 1012 1015 J1004 1005 1007 1008 1010 1011 P1002 1003 W100 105 TOP CLAMP CABLE CLAMP SHIELD CONN 6 PIN CONN 8 PIN CONNECTOR 48 PIN 3 ROWS CONN BERG 2 PIN 7011 302B 7011 304 5C 7011 305B TE 115...

Page 88: ...Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 89: ...Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 90: ...V CONNECTOR 48 PIN 3 ROWS TRANS N CHAN MOSPOW FET 2N7000 TO 92 RES 1M 10 1 2W COMPOSITION RES 10 5 1 4W COMPOSITION OR FILM RES 100K 5 1 4W COMPOSITION OR FILM RES 10K 5 1 4W COMPOSITION OR FILM RES 6...

Page 91: ...Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 92: ...Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 93: ...n for damage 1 2 Installation and removal 3 18 Instruction manual 1 2 J Jumper installation 3 3 Jumper removal 3 3 K Keeping connectors clean 4 16 L Low level resistance measurements 4 9 M Magnetic fi...

Page 94: ...ipment contents 1 2 Single card system 3 10 Single ended switching 2 6 Special handling of static sensitive devic es 5 13 Specifications 1 2 T Testing with matrix cards 4 10 Thermoelectric generation...

Page 95: ...alibration only Certi cate of calibration required Data required attach any additional sheets as necessary Show a block diagram of your measurement system including all instruments connected whether p...

Page 96: ...Keithley Instruments Inc 28775 Aurora Road Cleveland Ohio 44139 Printed in the U S A Artisan Technology Group Quality Instrumentation Guaranteed 888 88 SOURCE www artisantg com...

Page 97: ...service in house repair center WE BUY USED EQUIPMENT Sell your excess underutilized and idle used equipment We also offer credit for buy backs and trade ins www artisantg com WeBuyEquipment REMOTE IN...

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