Narrow Single-ended SCSI Bus Expander


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Narrow Single-ended SCSI Bus Expander  

Narrow Single-ended SCSI Bus Expander sends and receives SCSI transmissions at maximum sustained SE SCSI data rate.
Extend Single-ended SCSI busExtend Single-ended SCSI bus
Isolate Narrow Single-ended SCSI bus segmentsIsolate Narrow Single-ended SCSI bus segments
Enclosed & Board-Level versions availableEnclosed & Board-Level versions available
May be used as Narrow (8-bit) LVD/MSE to SE ConverterMay be used as Narrow (8-bit) LVD/MSE to SE Converter
Narrow Single-ended SCSI Bus Expander MS8A
Narrow Single-ended SCSI Expander MS8A
OEM's Custom Modifications to Your Specs. SCSI expander products and our newest LVD version. Includes: SCSI Converters/Extenders, Fiber Optic Extenders, SCSI Bus RegeneratoRs, SCSI ASICs, SCSI Quiet Cable and SCSI Cable TestersOEMs Custom Modifications to Your Specs
Narrow Single-ended SCSI Bus Expander MS8 and MS9

Quick Reference: Models Available Specs Ordering Guide


Narrow Single-ended SCSI Bus Expander MS8 and MS9


For a printable version of this information, please see the PDF version of this data sheet.

When your Narrow Single-ended (SE) SCSI bus is just a bit too short, there is a simple, economical solution: Paralan's Models MS8A and MS9A SCSI Expanders. A Paralan Expander sends and receives SCSI transmissions at maximum sustained SE SCSI data rate.

No need to modify software or hardware! Does not consume a SCSI ID. Target and initiators may be located on both the A and B sides of the Expander. Just connect your SCSI cables to a Expander and all devices on the bus will be available at an extra bus length. It's as easy as that!

SCSI too short?

To obtain one extra SCSI length, simply select the Expander model appropriate for your installation and plug in your cables. Daisy chaining of two or more Expanders can achieve even longer extension (see drawing below). This configuration with Model MS8A Expanders works well to extend a single-ended bus segment. A full SE cable length can be used on the end segments and up to 40 feet (12 meters) of cable can be placed between the two MS8As to achieve a total distance of 43 feet (13m) to 80 feet (24m) depending on the speed of the SE bus. For a discussion on SCSI Extension see the Extending SCSI page, and the article The Case for SCSI Expanders.


Using MS8 Expanders in a back to back connection. This configuration works well to extend a single-ended bus segment


SCSI devices need isolation?

Devices on one side of the Paralan Expander may be disconnected and not affect devices on the other side, as the signals on each side are isolated.

Paralan Expanders -- Not just repeaters! Cable causes timing delays of approximately 1.5 ns per foot of length. When SCSI specified cable length is exceeded, this cable-caused delay would normally cause a system to malfunction. Logic circuitry in Paralan's Expanders manages this delay such that disconnect, reconnect, arbitration and all other SCSI features are not affected. The SCSI signals are regenerated, reshaped, and retransmitted, all transparent to the hardware, the software and the operator. Paralan's exclusive Auto Sense™, standard on all Paralan Expander models, automatically detects correct termination power, solving many initial installation problems.

All Paralan Expanders are compatible with all devices that conform to the full ANSI X3T10 standards through SPI-3 (Ultra160). They are available either as stand-alone units utilizing line voltage (Model MS8A), or as board-level units for installation in other equipment (Model MS9A).

Converters and Expanders for LVD, HVD and SE SCSI

Paralan also has expanders for extending and/or converting between High Voltage Differential (HVD), LVD or Single-Ended (SE) SCSI devices.

Paralan is dedicated to SCSI, and to making your SCSI-interfaced components work to their full potential. We're known as the company that makes SCSI work, because our interface products reliably extend the capabilities of the SCSI bus. Paralan can match your SCSI needs with custom SCSI components, modifications to standard Paralan products, or even with custom products! Paralan is ready to meet your exact requirements by applying our SCSI-savvy engineering - from SASI through Ultra320.


MS8A/MS9A Narrow SE SCSI Expanders
Relative Humidity: 0 - 95% non-condensing
Operating Temperature: 0 - 50°C
Storage Temperature: –25 - +75°C

MS8A: 1.5 lb (0.6 kg)
Shipping weight, 4 lb (1.8 kg)
MS9A: 2.5 oz (0.1 kg)
Shipping weight, 2 lb (0.9 kg)

Power Requirements
Stand-alone units (MS8A): 100 - 250 VAC, 50/60 Hz auto select
Board-level units (MS9A):
5 V dc ±5%

Safety Approvals

FCC Class A, CE

SCSI Connectors
MS8A: 50-pin centronics-type (Shielded, Alt. 2 - A Cable)
MS9A: 2 rows of 25 pins (Unshielded, Alt. 2 - A Cable)

Parallel Transmission Rate:
Up to 20 MBytes/sec Ultra SCSI
Protocols: ANSI X3T10 SCSI standard

Physical Size: (MS8A)
Height: 1.6 in. (41 mm)
Width: 4.1 in. (104 mm)
Depth: 4.0 in. (106 mm)
Height: 0.4 in. (10.2 mm)
Width: 3.880 in. (98.5 mm)
Depth: 4.5 in. (114 mm)

Two year limited warranty

For complete dimensions see outline drawing.

Ordering Guide

Model Numbers Description
Stand-Alone Board-Level   
MS8A MS9A SCSI Bus Expander for Narrow (8-bit), Single-ended SCSI
Rack Mount Expander Box (rack mount up to 3 SCSI Expanders)
5-1/4" Half Height Drive Bay Mounting Bracket & Faceplate for MS9A
SCSI Quiet Cable™   (specify length)


9 TO 5 COMPUTER: Global Value-Added Distribution of NEW, used and refurbished computer periphery by a family-owned and operated company since 1979- distributing internationally computer related peripherals on the new, used and refurbished levels. HP, Compaq, IBM, CISCO, 3COM, APPLE, SEAGATE, and other major branded products as well as a MAJOR focus on Mass Storage related drives, media, storage racks, tri-optic barcode labels, libraries, autoloaders, duplicators, jukeboxes, HBA's, JBOD, Raid, SAN, NAS and software solutions.

As our stock of NEW, used and refurbished storage equipment changes daily, be sure to use our online chat service to get "real time" pricing from a knowledgeable sales technician. We also offer the lowest priced storage media on the net. Contact us now for drive rental, repair, duplication, software solutions or professional consultation.

*Buying refurbished can be better than buying new because flaws have been found and fixed, once it is deemed to be complete and in good working order it is repackaged to be sold at a lower price as refurbished.

© Copyright 2003.
*Price and availabilities subject to change without any notice. Not responsible for typographical errors.

Paralan SCSI products, Narrow Single-ended SCSI Bus Expander