Raspberry Jam (RJAM) Universal Digitizer

Manual

Note

All models of Raspberry Shake, including the RS1D, RS3D, RS4D, RBOOM, RS&BOOM and RJAM use the same software. Sections of the Quick Start Guide have been tailored to each product but the overall manual applies to them all. Other specific manual sections, like this one, have been created to address issues specific to the individual products.

Technical Specifications Documents

Raspberry Jam Universal Digitizer (RJAM) Technical Specifications Sheet

Note

Unlike other Shake products, the RJAM has no long period extension (from 4.5 Hz to ~2 seconds) as this would be undesirable for and incompatible with active sensors.

For details on the RJAM’s instrument response, see: Raspberry Shake RJAM

Design and Customization

The RJAM digitizer was designed to work with most seismic sensors and supports 3-channels of single-ended and differential-ended signal inputs, passive and active sensors.

Through-hole mountings are provided for resistors and capacitors to make it easy for electronics engineers and power users/ Do-It-Yourselfers to swap out components. The system is highly customizable. If you prefer the Raspberry Shake to do the customization for you, see: Raspberry Jam Universal Digitizer (RJAM) Customization. After you have reserved your RJAM at shop.raspberyshake.org, please fill out this document and return it to us at sales@raspberryshake.org. If you have ordered more than one RJAM, please send us this information in a Google Spreadsheet.

Warning

The RJAM board is ESD sensitive, and ESD precautions must be taken when soldering components and hooking up sensors. Even small ESD events can damage the response of the RJAM and cause small signal accuracy or reliability issues, both of which are difficult to detect but cause signal distortion. Also, be sure to populate the card with the appropriate resistors and capacitors BEFORE hooking up any sensors.

Warning

Like any digitizer not inside of a metal enclosure, you should be careful with any RF sources in the area.

Channels (as labelled on PCB board):

Channel # Resistors Capacitors
1 R13,R14,R15,R16,R24 C29,C30,C31,C32
2 R22,R34,R35,R37.R38 C23,C24,C58,C59
3 R30,R52,R53,R55,R56 C33,C34,C62,C63

Component Groups:

Group Sensor Type Components
R[damp] Passive with signal output 0 - 3 Volts Damping (“Shunt”) Resistors: R22,R24,R30
R[a] Active/ Passive with signal output >3V R13,R14,R35,R37,R53,R55
R[b] Active/ Passive with signal output >3V R15,R16,R34,R38,R52,R56
C[a] Any, optional LP Filter Capacitors: C23,C29,C31,C33,C59,C63
C[b] Any, optional LP Filter Capacitors: C24,C30,C32,C34,C58,C62

Note

Filter capacitors C[a] and C[b] are optional and can be included to provide, for example, a single-pole low-pass filter at 50 Hz. Filter capacitors were included in board design to provide some minimal protection to keep 50/60 Hz electrical noise out of the system. This low-pass filter is followed by a multiple pole digital LPF with a -3 dB frequency at ~40 Hz. The capacitor selected is best if it is a film type capacitor. If a ceramic capacitor is used, make sure it is rated at 25V or above. Do not use polarized capacitors. For film capacitors, use any type with a voltage rating above 10 volts.

Examples

Passive Sensors

Examples of passive sensors that RJAM is compatible with:

Manufacturer Sensor Notes
Many Geophones Racotech RGI-20DX has been tested (WARNING: We do not recommend the RJAM for small, low coil resistance (e.g., 380 Ohms), low generator constant (e.g., 28.8 V/m/s) 4.5 Hz geophones. Use the RS1D or RS3D instead.)
ASIR A_F2-GS-70  
Geospace

GS1

HS

 
Kinemetrics SS-1 Ranger  
Metry

F41-15.0

F50-4.5

F72-[2.0,4.5]

G88-[2.0,4.5]

G202-1.0

G110-1.0

previously IESE
Sercel L-4C previously Mark Products
Teledyne Geotech

S-13

GS-13[BH]

GS-21

 

Active sensors

The RJAM is compatible with the following active sensors and many more:

Manufacturer Sensor Known* Differential Voltage** Notes
Chaparral

Model [25,25/21]

Model 50

Model 50a

Model 60/64; 60Vx

Model 60UHP

None

Assuming 40V pk-pk Diff. output; data sheet is inconclusive

None

Sensor is 44V pk-pk Diff. When used with 40V pk-pk Diff input, signal will clip at ~90% of sensor’s full-scale

36V pk-pk Diff. actual. Use 40V Diff input.

GeoSIG AC-23 20V pk-pk Diff.
Geotech

KS-[1,2000,5400]

PA23

S-230

S-13 and other passive sensors

None

Assuming 40 V differential output

Assuming 40 V differential output

See previous table

Guralp

[3,5T,6,6T,40] Series

Fortis

None

None

Kinemetrics

Episensor [2,ES-T,ES-U2]

HypoSensors (FBA ES-DH)

FBA23

SBEPI (202)

10

We are guessing at what the actual value is, which is 40V Diff input. The +/-5V Diff input is not supported.

None

See above “Recommended component values for active sensors with 10V Differential outputs - FBA23 specific”

None

Lennartz LE-3D[lite/5s] MKIII 40V input comes close though the dynamic range is reduced. Better would be a 30V input range.
Metrozet

MBB-[1/2]

PBB-200H

40

None

None

Nanometrics

Trillium Compact[PH,AT]

Trillium 120[Q/QA]

Titan

40

40

40

None

None

None

RefTek (Trimble)

151B-120

147A

None

None

Seismowave

LP[ZA,HA]

MB3 A

Assume output is 40V pk-pk Diff., but would be probably better served with a 50V pk-pk Diff. input structure.

Assume output is 40V pk-pk Diff., but would be probably better served with a 50V pk-pk Diff. input structure.

Steckeisen STS[2,2.5,5A,6A] Unsure what output level actually is. Assume output is 40V pk-pk Diff., but would be probably better served with a 50V pk-pk Diff. input structure.

(*) Known = we have tested them in the lab

Note

(**) We assume that, in the seismology world, “40V peak-to-peak differential” output means that the output voltage of each signal line is swinging +/- 10 Volts with respect to ground. We have made this example list with that definition in mind, though it seems that in the seismology world the manufacturers are not consistent with how they specify the output level. In the end, the client is responsible for researching the solution and removing ambiguity surrounding how the manufacturer of their sensor(s) define the output level.

Note

Active sensors must be externally powered.

Cable diagram and connector specifications

Raspberry Jam Universal Digitizer (RJAM) Cable Diagram Sheet

The RJAM turn-key solution ships with an Amphenol PT07A-12-10S female connector. In addition to the sensor and cable, you will need to provide the male counterpart to this connector. We recommend the Amphenol PT06A-12-10P(SR). These are available on Mouser and Digikey. This can be purchased separately at shop.raspberryshake.org.