APO Custom Telco Cable

• Introduction
• Specifications
• Wiring of End 1
• Wiring of End 2

Introduction

Apache Point Observatory uses custom Telco cables to connect harmonicas (a set of 8 RJ-11 jacks connected to a male telco connector) and/or patch panels (multiple harmonicas mounted in a panel) together. The wiring was chosen so that RS-232 transmit and receive are twisted with their respective ground, and the two handshake lines are twisted together. Note that APO uses USOC-wired harmonicas and patch panels with sets of eight 6-wire 6-position RJ11 jacks (this is one of several standard types).

The cable uses female telco connectors. This is the opposite of typical phone cables, and is intended to reduce mix-ups.

Specifications

• The cable has a female telco connector at each end.
• The length is specified elsewhere.
• The cables are wired as described below.
  • Note that each end is wired differently.
  • Colors are shown as Black/White, meaning a black wire with a white stripe.

Wiring of End 1

pin	color		pin	color
01	Blue/White	26	White/Orange
02	Orange/White	27	White/Blue
03	Green/White	28	White/Green

04	Brown/White	29	White/Gray
05	Gray/White	30	White/Brown
06	Blue/Red	31	Red/Blue

07	Orange/Red	32	Red/Green
08	Green/Red	33	Red/Orange
09	Brown/Red	34	Red/Brown

10	Gray/Red	35	Black/Blue
11	Blue/Black	36	Red/Gray
12	Orange/Black	37	Black/Orange

13	Green/Black	38	Black/Brown
14	Brown/Black	39	Black/Green
15	Gray/Black	40	Black/Gray

16	Blue/Yellow	41	Yellow/Orange
17	Orange/Yellow	42	Yellow/Blue
18	Green/Yellow	43	Yellow/Green

19	Brown/Yellow	44	Yellow/Gray
20	Gray/Yellow	45	Yellow/Brown
21	Blue/Purple	46	Purple/Blue

22	Orange/Purple	47	Purple/Green
23	Green/Purple	48	Purple/Orange
24	Brown/Purple	49	Purple/Brown

25	Gray/Purple	50	Purple/Gray

Wiring of End 2

pin	color		pin	color
01	White/Orange	26	Blue/White
02	White/Blue	27	Orange/White
03	White/Green	28	Green/White

04	White/Gray	29	Brown/White
05	White/Brown	30	Gray/White
06	Red/Blue	31	Blue/Red

07	Red/Green	32	Orange/Red
08	Red/Orange	33	Green/Red
09	Red/Brown	34	Brown/Red

10	Black/Blue	35	Gray/Red
11	Red/Gray	36	Blue/Black
12	Black/Orange	37	Orange/Black

13	Black/Brown	38	Green/Black
14	Black/Green	39	Brown/Black
15	Black/Gray	40	Gray/Black

16	Yellow/Orange	41	Blue/Yellow
17	Yellow/Blue	42	Orange/Yellow
18	Yellow/Green	43	Green/Yellow

19	Yellow/Gray	44	Brown/Yellow
20	Yellow/Brown	45	Gray/Yellow
21	Purple/Blue	46	Blue/Purple

22	Purple/Green	47	Orange/Purple
23	Purple/Orange	48	Green/Purple
24	Purple/Brown	49	Brown/Purple

25	Purple/Gray	50	Gray/Purple