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Small beige DB9 female-to-female null modem adapter

Monoprice Inc.

Monoprice Inc. 101204 DB9 Female/Female Mini Null Modem Adapter

SKU CH-9VTF-FZE59

Connects two serial devices via crossed RS-232 wiring for direct file transfer in a compact female-to-female form factor

  • FeaturesBuy with Confidence: With Monoprice's Lifetime Warranty on a
  • Connect two computers for file transfer using crossed transmit and receive lines
  • Miniature DB9 female-to-female design fits tight spaces behind equipment
  • RS-232 serial null modem with nine-pin D-sub connectors on each end
  • Monoprice lifetime warranty backs every cable and adapter sold
  • Model 101204 provides direct device-to-device link without a modem

DB9 Null Modem Adapter

This miniature adapter provides female DB9 connectors on both ends for direct RS-232 communication between two devices. It crosses the transmit and receive lines internally so data can flow without a modem. The compact form factor suits tight ports on legacy equipment or industrial controllers.

Sustained Serial Throughput

Because the adapter contains no active electronics, signal quality depends entirely on the cables and ports attached to it. Under continuous file-transfer loads the crossed wiring remains passive, so performance is limited by the serial controllers at each end rather than by the adapter itself.

Plug-and-Play Installation

Simply insert each female end onto the male DB9 ports of the two devices; no drivers or configuration are required. The only common issue is mismatched pin-outs on non-standard cables, which can prevent the crossed signals from aligning correctly.

Highlights

  • Connect two computers for file transfer using crossed transmit and receive lines
  • Miniature DB9 female-to-female design fits tight spaces behind equipment
  • RS-232 serial null modem with nine-pin D-sub connectors on each end
  • Monoprice lifetime warranty backs every cable and adapter sold
  • Model 101204 provides direct device-to-device link without a modem

Specifications

BrandMonoprice
Model101204
Part Number101204
FeaturesBuy with Confidence: With Monoprice's Lifetime Warranty on all Cables, you can rest assured we stand behind our products and our customers.

Questions about this item

Does the DB9 null modem adapter draw any power or generate heat when left connected all day?

It is a passive wiring adapter with no active electronics, so it draws no power and produces no heat during continuous use.

What cables or ports must I already have to use this female-to-female DB9 null modem?

You need two male DB9 RS-232 cables or devices with male DB9 ports to plug into each side of the adapter.

Will this mini null modem work with legacy 9-pin serial equipment that expects crossed transmit and receive lines?

Yes, the receive and transmit conductors are crossed inside the adapter, matching the pin-out required by classic RS-232 null-modem connections.

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