[CA] Providing Navigation Input to a ST6000 Course Computer

[timtyler]

I have an older ST6000 Autohelm system. The control head is a ST6001+ and the course computer is a ST6000 (Z123).

My first question concerns the course computer. Is this commonly referred to as anything else? I can find little to no documentation that refers to this computer other than the Autohelm Inboard Autopilots (ST6000 and ST7000 systems) Service Manual.

Second question: I would like to connect this system to a newer Furuno chartplotter via NMEA 0183 to get tracking information. Since the chartplotter is new, it employs a differential interface with two signal wires. The ST6001+ control head is expecting a single ended interface implemented with one signal wire and a common ground. Will I get a proper signal if I wire these two together with the A+ chartplotter signal wire going to the ST6001+ plus connection and the chartplotter ground going to the ST6001+ minus connection? Seems like I should.

Third question: Assuming the above will work, is it possible to connect a GyroPlus 2 unit to the system by moving the Fluxgate compass connection to it and connecting a Seatalk cable from the GyroPlus 2 to the ST6001+? Will this work, or am I just asking too much from this old reliable system?

Thanks.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Tim,

As you have suggested the Z123 is indeed the correct name for an autopilot course computer and was part of the AH6000 Stern Drive (see diagram below). Information for that autopilot may be found here.



Unfortunately, neither parts nor service are available any longer for this 20+ year old autopilot design and support is generally limited to providing access to the autopilot's owner's manual. That said, the ST6001+ autopilot control head is of a later design. On the back side of the ST6001, you will find a 4800 NMEA 0183 input interface. Interfacing it to the 4800 BAUD NMEA 0183 v2.1 (or later) output of a third party chartplotter / GPS navigator may then permit the third party chartplotter / GPS navigator to supply the autopilot with navigational data in support of the autopilot's Track feature.

The Smart Heading System was not designed for use with the Z123 autopilot course computer.

[timtyler]

Thanks for replying so quickly. So, just to recap (and make sure I understand):
- The common name for the course computer is Z123.
- The ST6001+ control head has a differential interface and NOT a single ended interface as I thought and should be wired as such...two data streams (an A+ and a B-) with no ground.
- The GyroPlus 2 unit will NOT work with my computer.

[Chuck - Raymarine - Moderator]

Tim,

Q1. The common name for the course computer is Z123.
A1. Correct

Q2. The ST6001+ control head has a differential interface and NOT a single ended interface as I thought and should be wired as such...two data streams (an A+ and a B-) with no ground.
A2. Correct

Q3. The GyroPlus 2 unit will NOT work with my computer.
A3. Correct.