Serial Communication Cables
A little background...
Historically, Optec's products and instruments have used a serial communication protocol to communicate with an external computer. Optec's RS-232 protocol implementation is a 3-wire subset of the official RS-232 specification. Over the years, our implementation has proven to be quite robust. Our latest cable product is a unique 3-wire RJ-12 to USB direct connect Serial/USB Cable designed especially for the TCF-S, IFW, and Pyxis rotator.
"Reverse" Cables and USB/Serial Cables
The TCF-S and TCF-Si focuser family, FocusLynx controller, IFW filter wheels, and Pyxis camera field rotators each use a modular RJ12 connector directly on the instrument or on a separate control box. These female RJ12 sockets all use the same pin configuration with RX, TX, and GROUND ports (see inset at lower left) which has historically been connected through a separate "Reverse" cable and Serial Port Converter. The simple flat "Reverse" cable was engineered such that any observatory user or installer with a standard telephone cable crimper could easily fabricate cables after fishing the flat 6-wire cable through mount, pier and floor conduits. A pre-wired "serial port converter" could be supplied for such installations making for an easy job of wiring up the observatory. Unfortunately, with the disappearance of dedicated DB-9 serial ports on today's computers, a third item, the USB-to-Serial Converter became necessary. This configuration has lead to a 3-piece communication wiring scheme that was less than optimal.
The Optec solution is the USB/Serial cable with an integrated USB converter. Currently all new Optec products include a 6-ft. USB/Serial cable as standard. Our other, longer cable lengths of 12, 25, and 50-ft. continute to be very popular and are available from stock. When requested, we can fabricate a custom length USB/Serial cable for any installation.
Complete USB/Serial Cables:
New Serial Cables with Integrated USB Converters
Recent advancements in USB-to-Serial converter technologies has allowed Optec to offer a single Serial / USB cable in place of the 3-piece configuration. These cables are available in standard lengths of 6, 12, 25, and 50-ft. Because the cable is standard RS-232 level on the long side of the cable, the 5-meter (16-ft.) length restriction for USB does not apply. Contact Optec Sales for custom lengths.
How to Order:
Original Style "Reverse" Cable:
Optec RJ-12 to RJ-12 "Reverse" Serial Cables.
Our original "Reverse" cables are still available in standard and custom lengths. Most are in stock for immediate shipment. Contact Optec Sales for custom length "Reverse" cables.
How to Order:
Optec Serial Port Converter:
Serial Port Converter - RJ12 (female) to DB-9 (female)
|The #17695 Serial Port Converter
can be used with any of the flat "reverse" cable listed
This modular adapter remains the simplest way to convert from
the flat Reverse cables to the DB-9 connector of any native RS-232
computer serial port.
USB to Serial Converters:
Other Cables and Converters:
The SSP photometer line and Perseus 4-port Instrument Selector each use a standard DB9 connector with standard RX, TX, and GND ports connected. A "Null Modem" serial cable is required to make the connection to a PC's 9-pin DB9 serial port. Available in lengths from 6-ft (2m) to 25-ft (8m) these serial cables feature a female DB9 connector on both end with locking thumbscrews.
The TCF-S and IFW hand control boxes each require an 8-wire Control Cable. This RJ45 connector to DB-9 is not a serial cable but carries the stepper control signals to the motor and returns either temperature information (TCF-S) or position information (IFW and older MAXfilter filter selectors).