401-943-1164 / US & Canada Toll Free: 877-943-1164

Model 700, Cat# 301030 RS232 Tri-State Box Interface Analyzer for Terminals, Kiosks, Computers & More

    EIA RS232 Interface AnalyzerEIA RS232 Interface AnalyzerEIA-CCITT MODEM TERMINAL INTERFACEModel 700 Tri-State DisplayEIA RS232 Interface Analyzer
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    • EIA RS232 Interface Analyzer
    • EIA RS232 Interface Analyzer
    • Model 700 Tri-State Display
    • EIA RS232 Interface Analyzer
Base Price:
Catalog No: 301030
Model No: 700
Description:Compatible with EIA RS-232, CCITT, V.24 & MIL-188C
Display:All modem & terminal interface signals
Product Type:Breakout Boxes/Interface Analyzer
Interface:RS-232 Interface
Application:Testing of computer's serial data interface
Feature:Tri-State LEDS display Red, Green, & Off to Indicate Signal Status
Ruggedized:Virtually indestructable

  • Tri-State LED's Display Red, Green, Orange & Off to Indicate Signal Status
  • National Stock Number, NATO Stock Number (NSN): 6625-01-585-9259
  • Cable Interface Diagnostic tools.
  • Cable Interface Testing.



Shipping Terms

Shipments are made via UPS Ground, unless otherwise specified. Freight charges are prepaid and added to your invoice. We can estimate the freight costs for you.

We can ship freight collect on your account, just provide your UPS Account Number.

We can also ship via the carrier of your choice. Provide the details and your account number.

Products shall be shipped F.O.B. Electro Standards' facility. Title to and risk of loss or damage to the products shall pass to you upon Electro Standards delivery of the products to a carrier for shipment. Title to software will remain with the applicable licensor. Electro Standards' prices do not include shipping and handling charges. Electro Standards reserves the right to use its own discretion in the manner and routing of shipments. Electro Standards shall be permitted to deliver products in separate lots.

Shipping Return Policy

  • To return an item, contact Electro Standards at 401-943-1164 to obtain a Return Material Authorization (RMA) number. RMA numbers are valid for 30 days after the date of the shipment and cannot be extended or re-issued. We are unable to accept returns without an RMA number.
  • All returns except those of defective product are subject to a 15% restocking fee, and additional charges for handling or freight are refunded only in cases of defective products.
  • Return freight must be shipped prepaid. We recommend that you insure the package as you are responsible for risk of loss on all returned packages. We recommend that all cartons are properly packed as Electro Standards is not responsible for product damaged en route. We do not issue call tags for product returns.
  • Returned product must be clean, undamaged, and complete with all manuals, accessories, documents and packaging. The items must be in a resalable condition.
  • The product must have with it a copy of the original invoice or packing slip and the appropriate RMA paperwork.
  • If your item is not working properly, please contact Electro Standards at 401-943-1164 for help in trouble-shooting your application.
  • If the product is defective, Electro Standards will repair or replace that item (at our discretion) upon receipt and evaluation of the original product.
  • Electro Standards reserves the right to authorize product returns after 30 days from the invoice date in some cases. If the product is accepted after 30 days, credit will be issued toward future pruchases only and some additional restocking charges may be applied.
  • All credits from RMAs must be used within one calendar year of issue.

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Model 700 EIA RS-232 Interface Analyzer, Breakout Box
Tri-State LED's Display Red, Green, Orange & Off to Indicate Signal Status

  • RS232 Breakout Box on GSA Schedule

  • National Stock Number, NATO Stock Number (NSN): 6625-01-585-9259

  • Ideal for Commercial-Off-The_Shelf (COTS) purchase applications

  • ESL Breakout Boxes are Made in the USA. *Lifetime Warranty!


  • Tri-State (3-color) LED Display for quick signal analysis.
    • The Model 700 utilizes state-of-the-art tri-state light emitting diodes to indicate the status of key signals at the EIA/CCITT data interface.
    • The use of Tri-State indicators allows the maximum efficient monitoring of bipolar interface signals.
    • They present the user with a maximum of signal status information.
  • Displays all modem & terminal interface signals
  • Compatible with EIA RS-232, CCITT V.24, and MIL-188C
  • Separate EIA cable facilitates use at either modem or terminal end
  • Test points to access all 25 pins of both DCE and DTE connector
  • Can also be utilized to determine custom cable designs
  • Completely portable: lightweight, pocket-sized, battery powered
  • Rugged aluminum case and metal hinge that will NOT break
  • Tests synchronous or asynchronous modems, terminals, multiplexers
  • 24 mini-switches, 4 mini-patchcords
  • Lifetime Warranty against manufacturing defects!
  • Comprehensive User's Manual
  • On GSA Schedule!


Model 700 EIA RS-232 Interface Analyzer is a diagnostic tool designed for use at the Standard EIA RS-232 or CCITT V.24 data interface of modems, multiplexers, terminals, and computers. It is simply inserted in series between the DTE (Data Terminal Equipment) and the DCE (Data Communication Equipment) to provide access to and monitoring of all data, timing, and control signals.

The Model 700 breakout box is of optimum design. It utilizes state-of-the-art tri-state light emitting diodes to clearly display polarity, activity and validity of all interface signals. Miniature rocker switches allow the user to program a 'make' or 'break' for each signal at the DCE/DTE interface. Mini-patchcords are provided for cross-patching or loopback patching of signals at the front panel test point array.

A complete table of EIA/CCITT standard interface signal descriptions is provided inside the unit for ready reference during testing. A covered compartment provides secure storage for mini-patchcords and an EIA ribbon cable. The Model 700 breakout box is battery powered for complete portability, pocket sized for convenience, and packaged in a study aluminum case with metal hinge for durability in field use.

 Front panel mini-switches, signal access posts, and mini-patchcords supplied with the unit allow you to gyrate/manipulate the serial connections and signal placement as required to get your two pieces of equipment properly connected.

Here is the best: When you have established a pin/signal interconnection that works between your two devices, read the jumper connections and the mini-switch connections that you observe on the front panel of the Model 700 and you have the design for the required interface cable!

Conclusion: Many serial data interface problems and data cable designs can be pinpointed and resolved with the Model 700. 


The Model 700 display consists of 14 "Tri-State" LEDs, each of which actually can display signal status in three colors (red, green, orange).  The LEDs can also be OFF (not illuminated), therefore that means each of the 14 LED's can give you four states of information... totaling 56 pieces of interface information! SIMULTANEOUSLY!

The four pieces of information for each signal are easy to understand. RED means the signal is in the "CONTROL OFF" state. GREEN means the signal is in the 'CONTROL ON" state. ORANGE means there is a proper clock/timing signal or a proper data stream signal on that line. LED OFF (not illuminated) means the signal is either too weak or that no signal is present.


  • Input Signal: /-25V per EIA RS-232
  • More pos than 2.5V = Green indication
  • More neg than -2.5V = Red indication
  • LED Circuit Input Impedance: Exceeds 30K ohms
  • Operating Temperature: 0°C to 50°C
  • Storage Temperature: -40°C to 90°C
  • Humidity: 10% to 90% without condensation
  • Size: 4.0" x 5.25" x 1.75" (10.2 x 13.3 x 4.5 cm)
  • Weight: 15 ounces (426 grams)
  • Power: Four 1.5V, size AA batteries
  • Display: 14 tri-state LED indicators
  • Test Points: 50 test points access all 25 pins on both DTE and DCE connector One spare LED access test point; One set of two voltage test points ( ) (-).
  • Switches: 24 Mini-rocker switches for on-off control of all signals between DTE and DCE.
  • I/O Connectors:
  • TO DCE, a 25-pin EIA socket.
  • TO DTE, a 25-pin EIA plug.
  • Cables & Patchcords:
  • One 10-inch EIA cable.
  • Three single (1-to-1) mini-patchcords.
  • One triple (3-to-1) mini-patchcord.
  • EIA/CCITT Modem terminal Interface Label: Attached to upper panel. Describes relationship between EIA, CCITT, Signal Nomenclature, and Signal Source.
  • Package: Aluminum case, metal hinge and clasp. Storage compartment for cable and mini-patchcords. Scuff-proof.

Model 700 is available to government purchasers on our GSA Schedule GS-35F-0286V. Call for discounted price and terms.

A manual accompanies each unit and provides application assistance. Need more help? Contact Electro Standards, provide the serial number of your Model 700, state your application and question, and you will receive a helpful answer..

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Electro Standards welcomes International inquiries: commutateur d'ordinateur,  equipo interruptor, interruttore del calcolatore, interruptor do computador, dator switch.

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