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Break Out  Boxes

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Handheld RS232/422 Serial Protocol Analyzers and Packet Sniffers from the  Experts at Benedict Computer.

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 Serial Data Line Monitor / Protocol Analyzer

DLM400  (Data Line Monitor) Package
DLM400 Product and Accessories

DLM400 Use Case
Configured to test GPS and micro Controller data

DLM400 that is
                          wired to Test TTL board level signals between
                          GPS chip and Controller 


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RS232, RS422, RS485 Serial Asynchronous / Synchronous Data Line Monitor / Analyzer

The DLM400 is a Battery Powered Serial Monitor, Tester, and Emulator for Analyzing, Viewing, and Uploading Data at Speeds to 230.4K . The DLM400 has Menu Selectable RS422, RS423, RS232, RS485  and MIL-Std-188-114 interfaces. It captures 304,000 events, exports, times, and does performance/ BERT testing.


The Worlds best Break Out Boxes since 1985

RS 232 Break Out Box

Bob 100 Compact Break Out Box

A compact, industrial strength, BREAK OUT BOX used to monitor and redirect RS-232-C circuits.
  • 102 high efficiency LEDs.
  • Breaks and redirects all 25 lines.
  • Four-state monitors on all lines on both DTE/DCE.
  • Two DB9/25 pole adapters plus conversion table.
  • Full cable test function and GPD test.
  • Bi-directional Current Loop test (4,10,20,60 mA).
  • Jumper cable set and 12 inch ribbon cable.
  • Easy operation, lightweight and compact.

One female and one male 25 pin Sub-D connector
Signal Status Display
Mark, Space, Clocking, None indication on all 25 pins on both sides of the breakout switches.
Access Sockets
Sockets are located on both sides of the breakout switches allowing direct access to both interfaces.

Jumper Cables / Patching
A sturdy set of jumper cables with high quality gold plated plugs is provided to allow cross patches of interface lines. Included are six two-pin jumpers plus two four-pin jumpers.

Ground Potential Differences Test Circuit
The different ground potentials of the two interfaced devices can cause problems with signal interpretation. The Circuit testing this difference makes use of G. P. D. monitor connected to the left side of switch #7.

Power/Test Voltage Sources
The basic function of the BOB100 do not require battery power. The tester can use one 9 volt battery for the purpose of generating + or + voltage for testing.

Physical (Hand Sized)
7.4 x 3.4 x .7 inches, 8.9 ounces.

Current Loop Test Circuit
The Current loop test circuit can be used to measure 4, 10, 20, and 60 mA circuits. The LED illuminates at 80% of the stated current. Maximum current is 3 times stated with an upper limit of 80 mA.

The BOB100 is supplied with a small leatherette case, jumpers, manual, battery connector, and 11 inch cable.

RS232 Line Voltage Monitor

RS232 Digital Line Voltage Monitor

  • Four-state monitoring of all lines
  • 24 green and 24 red high bright LEDs
  • Two DB25/9 mini adapters included
  • DB25 and DB9 described on faceplate
  • Loop-back function to test cables
  • Compact/ rigid design
  • User manual, pouch for carrying

This compact tool shows the state of all lines in a glance. It connects to, can convert between, DB25 and DB9 interfaces. The face plate gives a complete description of all signals with their pin numbers and explains the DB25/9 conversion. It is constructed by field service engineers and famous for its convenience in use and reliability.

The Comtest RS232LM offers features not available on other testers of its kind. The DB25/9 pole adapters make it not only to test DB25 and DB9 pole communication but can also convert between them. The logical face plate provides complete and easy to read information.

It is interface powered. The high bright LEDs show signal strength, the load per line is typically 1mA with a 6.6volt signal. The LEDs are mounted behind a structured panel, they do not glance and give distinct light in contrast with the black face plate.

In addition to monitoring line activity it can it can be used as loop-back unit to test ready installed cables using signal ground as return wire.

To Order or ask a question please Call us at
Benedict Computer

  Williamsburg, VA 23188/ (650) 323-0148

(No Voice Mail; you will get a human or a  human will call you back!)G