Null Modem Cables
- Compact null modem serial connection
- Provides "cross-over" connection for serial devices
- DB9 Female connector on each end
General Description
These Null Modem cables can be used to connect two serial ports together, allowing communication between them. The Transmit signal of one side is connected to the Receive signal of the other. Flow control lines and other signals are also connected. Applications include PC serial communications and other devices.
The exact connections are as follows:
| Signal | DB9 Pin | DB9 Pin | Signal |
|---|---|---|---|
| Receive | 2 | 3 | Transmit |
| Transmit | 3 | 2 | Receive |
| DTR (Data Terminal Ready) | 4 | 6, 1 | DSR (Data Set Ready), Carrier Detect |
| Ground | 5 | 5 | Ground |
| DSR (Data Set Ready), Carrier Detect | 6, 1 | 4 | DTR (Data Terminal Ready) |
| RTS (Request to Send) | 7 | 8 | CTS (Clear to Send) |
| CTS (Clear to Send) | 8 | 7 | RTS (Request to Send) |
Optional Extra-Long Jack Screw Kit
Winford now offers extra-long jackscrews as an accessory that can be purchased separately if daisy-chaining cables is desired. The existing thumbscrews would be removed and the long jackscrews installed in their place, and secured with the included nuts and washers on the back of the cable. See photo on right for example or order below. The jack screws are designed to accept the thumbscrews on a mating cable, helping secure the cable firmly in place.
These 35mm Jack Screws can also be used to panel mount D-Sub Extension Cables. We recommend using a max of 1/16" (0.0625") for panel thickness when mounting any D-Sub extension cables. For D-sub cutout recommendations please see our D-Sub Panel Cutout Drawing.
Pricing and Ordering
| Product # | Description | 1+ | 10+ | RoHS | Buy Now |
|---|---|---|---|---|---|
| NMC9F9F-6 | Null Modem Cable, DB9 Female to DB9 Female, 6 Ft | $3.99 | $3.75 | Yes |
| Quantity | Price |
|---|---|
| 1+ | $3.99 |
| 10+ | $3.75 |
Extra-Long Jack Screw Kits
Extra-Long Jack Screw Kit for Daisy-Chain Applications
| Product # | Description | 1+ | 10+ | 50+ | RoHS | Buy Now |
|---|---|---|---|---|---|---|
35mm Jack Screw Kit |
||||||
| DJSK-35.0-A | D-Sub #4-40 Jack Screw Kit, 35mm shaft length; 2 each of jack-screws, flat washers, lock washers, nuts | $4.50 | $4.20 | $4.00 | Yes | |
| Quantity | Price |
|---|---|
| 1+ | $4.50 |
| 10+ | $4.20 |
| 50+ | $4.00 |
All of the above items are normally stocked. Please call us if you need to verify availability for a specific quantity, or for pricing at higher quantities. Please visit our ordering page for our ordering policies and a list of ordering methods.