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

309927 Model 9927 4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch

    4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch
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    • 4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch
    • 4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch
    • 4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch
    • 4-Channel DB9 & 1 Channel RJ45 Cat5e A/B Switch
Base Price:
Catalog No: 309927
Model No: 9927
Cable Type/Port Connector:RJ45, DB9 Switch Ports
Channels per Switch Chassis:5
Manual Control/No Power Required:LineSelect® Manual Operation
Channel Control:Group Channel Control
Local Control:Rotary Knob


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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Multi Interface Copper Network Switches
Cat5e Manual Network Switch, RJ45, DB9

  • Model 9927 Five-Channel A/B Switch: Four-Channel DB9, Single Channel RJ45 Cat5e, Manual, Rackmount

  • Simultaneously switches four DB9 channels, independently switches the single RJ45 Cat5e Channel


    • (3) DB9 female connectors labeled A, B, and COMMON for each of four channels.
    • (3) RJ45 female connectors labeled A, B, and COMMON for the one RJ45 channel.
  • FRONT PANEL CONTROL: (2) Rotary switches on front panel.
    • One knob for Channels 1, 2, 3 and 4 (DB9 interface).
    • The other knob switches Channel 5 (RJ45 Cat5e interface).
  • POWER: No power required.  Manually operated.
  • DIMENSIONS: Rackmount configuration, 19.0" W x 1.75" H x 8.63" D. (48.3 x 4.5 x 22.1 cm)
  • WEIGHT: Approximately 4.3 lbs. (2.0 kg)

FIVE-CHANNEL A/B SWITCHING APPLICATION: The drawing illustrates five channels of A/B switching.

  • Four channels of DB9 A/B switching.
  • Simultaneously switch all four DB9 A/B switches between position A and position B.
  • A single channel of Cat5e RJ45 A/B switching.
  • Independently switch the Cat5e Channel between position A and B.

LineSelect® Model 9927 four DB9 Channels, 1 RJ45 Cat5e Channel


  • Allows quick connection to any one of two DB9 devices from one COMMON device for each of four channels.
  • Allows quick connection to any one of two RJ45 Cat5e networks or devices from one COMMON device.
  • The RJ45 channel is certified for Ca5e compliance.
  • Manual operation via two front-panel rotary switches.
  • High quality sealed switch with self-wiping low impedance contacts.
  • Transparent to data speed and format.
  • Switches all 9 pins of the DB9 interface via break-before-make rotary switch.
  • All 8 pins of the RJ45 interface are switched via break-before-make rotary switch.
  • Simultaneously switches four DB9 channels via one front-panel rotary switch.
  • Independently switches the RJ45 Cat5e Channel via the second front-panel rotary switch.
  • Eliminates the need to plug and unplug cables.
  • No external power required.
  • Improves computer network efficiency by allowing sharing of peripherals.
  • Custom length DB9 and RJ45 cables available for your switch installation.
  • Attractive all metal black box packaging provides EMI/RFI shielding.
  • Lifetime warranty against manufacturing defects.

The Model 9927 Five-Channel A/B Switch is comprised of four channels of DB9 interface and one channel of RJ45 Cat5e interface.  The front-panel has two rotary switches.  One rotary switch simultaneously selects the A or B position for all four of the DB9 channels.  The second rotary switch independently selects the A and B position for the single RJ45 Cat5e channel.

The unit is manually operated, requiring no power.  Port selection is quick and easy via two front panel rotary switches.  The Model 9927 is enclosed in a 1U, full rack size, all metal black chassis designed to provide EMI/RFI shielding and fit in a standard 19" rack.

Electro Standards can supply all your Network Cable requirements. Click here to reach our CABLES, COPPER NETWORK Webpage.

For custom network switches call our friendly customer support staff at 401-943-1164, email eslab@electrostandards.com, or complete our online form: /Products-Custom/Copper-Switch/

Don't forget to order your DB9 Cables! 

Custom Length DB9 cables available for your switch installation. 
State cable length when ordering.
Part Number  Description
990127  DB9 F/F, 9-Conductor Unshielded PVC Cable
990125  DB9 M/F, 9-Conductor Unshielded PVC Cable
990126  DB9 M/M, 9-Conductor Unshielded PVC Cable 

All data switches, data communication products, and data acquisition products are subject to a one year warranty against manufacturing defects.  The limit of ESL liability is limited to the cost of the ESL product provided.

*Prices online are subject to change and verification.

All ESL products are available for export.

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

Available Combo Deals