NIIS Electronics

GUMP Preamplifier

The General Use Multi-channal Preamp (GUMP), provided by Infrared Labratories, Inc., is used as the preamplifier needed by the Leach controller. The Gump consists of a mainboard and four daughter boards. The GUMP has its own power supply which sits externally to the preamplifier itself and the controller (pictures of the power supply). The mainboard provides the connections to all four daughter boards,the power supply,the connections to the leach Controller and the circular connector which goes directly to the array inside the instrument. Connected to the mainboard is the GUMP end panel,which corresponds to the black end of the box shown in the GUMP pictures. This panel is where the connectors to the Leach controller and the power supply enter the GUMP. As is stated on the Leach Controller page, the information produced from the array inside the instrument first travels through the GUMP via the mainboard, then uses the daughter boards to vary the voltages and gains before the information is sent to the Leach controller. The daughter boards connect “vertically” into the four parallel connector slots shown on the mainboard. Detailed circuit diagrams for the daughter boards, as well as for the mainboard can be found in the following PDF document: GUMP.pdf


Left: Picture of the Mainboard without the daughter boards
Right: Diagram of the Mainboard (click for a larger image)

End panel: connects mainboard with the power supply and Leach controller

Parts List (populated for 4 Daughter Boards):

Quantity Description
1 connector, 41 PIN Bulkhead Recepticle
1 connector, D-SUB 9 pin male right angle, PCB mount
1 connector, DUAL DSUB 37 pin male right angle, PCB mount
1 enclosure, Lansing box
3 connector, D-SUB mounting Hardware kit
16 capacitors, 10 UF/25 VOLT
30 capacitors, 0.1 UF caps
8 connectors, Header pins, Breakaway type

Daughter Boards

Picture of one of the daughter boards

Diagram of a daughter board, notice that it corresponds to the image above

Parts List:

Channel Components Channel 1 Channel 2 Channel 3 Channel 4 Channel 5 Channel 6 Channel 7 Channel 8
0.1 UF - SM 25V C3, C4 C5, C6 C36, C35 C43, C42 C50, C49 C57, C56 C64, C63 C71, C70
68 PF C1 C2 C31 C38 C45 C52 C59 C66
4 kΩ R1 R8 R9 R13 R17 R21 R25 R29
8 pin OP Amp socket U1 U2 U3 U4 U5 U6 U7 U8
1 kΩ R2 R5 R12 R16 R20 R24 R28 R32
jumper R4 R7 R11 R15 R19 R23 R27 R31
jumper J1, 2-4 J2, 2-4 J6, 2-4 J8, 2-4 J10, 2-4 J12, 2-4 J14, 2-4 J16, 2-4
jumper J4, 1-3 J4, 1-3 J4, 1-3 J4, 1-3 J4, 1-3 J4, 1-3 J4, 1-3 J4, 1-3
open R3 R6 R10 R14 R18 R22 R26 R30
open C11 C13 C32 C39 C46 C53 C60 C67
10 kΩ C12 C14 C34 C41 C48 C55 C62 C69
OPA 627 AP U1 U2 U3 U4 U5 U6 U7 U8

Power Supply Components
0.1 UF - SM 25V C15, C16, C7, C18
10 UF, 25 Volt C19, C20

Voltage Offset Components
0.1 UF - SM 25V C23, C24, C25, C26
jumper (J3) pins 1-5, applied to channels 1 thru 8

Board Connector
96 pin IDC, right angle