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#1
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Question on autopilot
In my 1978 Swan 411 there is an old NECO autopilot. I recently fixed
some minor faulty circuitry and it now works as it is supposed to do. Too bad that it is a vintage device and, for example, does not have a NMEA input, the course is set on an absolute 360 deg dial and there is no whatsoever display that gives information on the set/actual course. I would like to upgrade it but the 12Volt/20A servomotor under the steering wheel works well and I would like to keep it: it is presently controlled by two relais'. Also the clutch works and there is a rudder feedback, probably a variable resistor, in the same assembly. Keeping them would reduce the cost by a relevant amount and, in particular, would almost zero the mechanical adapting of the steering system. On the market there are many display/control units available with all the modern facilities; using one of them should not be impossible. The main problems I foresee a i) compatibility between the output of the new unit and the relais/servomotor, and ii) possible installation of a new rudder feedback unit. Has anybody in the NG faced those problems and solved them? Daniel |
#2
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Question on autopilot
I'm in about the same situation, having a pre-ST autohelm 3000 that is under
powered and doesn't take NMEA input. Otherwise it works fine in calm water with the course set manually.. I have already found a solution to the increase in power, however I'm still searching for an upgrade to the control head. Be advised that none of the pre ST autohelm/Raymarine pilot will except NMEA input.. Even the Z80 interface seems to dislike the current 0183 formats. Then we get into the ST models. Even some of these early ST models still required an interface to convert the NMEA to SeaTalk before it goes to the AP.. I investigated a ST5000 on ebay that had a location for the NMEA connection and the markings were molded into the case, but the connector pins holes were empty.. Must have been a very early release.. Then there is the problem of your drive motor clutch.. I believe that the ST5000 is the first model to have a clutch control in the control head.. Here again, I would approach this with caution since there are going to be control heads sold for tiller pilots that don't require a clutch release. I would recommend staying away from the current generation since the control head don't necassarily have the course computer in them, just some secondary circuits, display and buttons. The course computer is incorporated in some other nav station equipment.. I think your approach is correct as you have evaluated each of the system components and determined what to keep and what to abandon.. Your boat size, like mine make it nearly impossible to purchase an off the shelf AP system.. My boat being 13.5 ton and tiller steered.. Even the largest tiller pilot system comes up short. Good luck. -- My opinion and experience. FWIW Steve s/v Good Intentions |
#3
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Question on autopilot
Steve,
I'm in the same situation as you, in that I have just sold my pre-NMEA AH3000 control head, with the intention of buying an ST3000 control head. I've had two good prices on buying just the control head as I am keeping the drive motor. Most companies want you to buy the complete system. Raymarine (UK) have confirmed that the ST will directly replace the AH but with the added facility of Seatalk. I have the interface from my previous boat, so will be able to marry both parts of the system into my GPS. I was intending to upgrade to an ST4000, but believe that I would have to install rudder feedback, as well as buying a fluxgate compass unit to feed the 4000. With just replacing the AH3000 with the ST3000, that will be all there is to it. regards, Philip, s/v Oyster "Steve" wrote in message ... I'm in about the same situation, having a pre-ST autohelm 3000 that is under powered and doesn't take NMEA input. Otherwise it works fine in calm water with the course set manually.. I have already found a solution to the increase in power, however I'm still searching for an upgrade to the control head. Be advised that none of the pre ST autohelm/Raymarine pilot will except NMEA input.. Even the Z80 interface seems to dislike the current 0183 formats. Then we get into the ST models. Even some of these early ST models still required an interface to convert the NMEA to SeaTalk before it goes to the AP.. I investigated a ST5000 on ebay that had a location for the NMEA connection and the markings were molded into the case, but the connector pins holes were empty.. Must have been a very early release.. Then there is the problem of your drive motor clutch.. I believe that the ST5000 is the first model to have a clutch control in the control head.. Here again, I would approach this with caution since there are going to be control heads sold for tiller pilots that don't require a clutch release. I would recommend staying away from the current generation since the control head don't necassarily have the course computer in them, just some secondary circuits, display and buttons. The course computer is incorporated in some other nav station equipment.. I think your approach is correct as you have evaluated each of the system components and determined what to keep and what to abandon.. Your boat size, like mine make it nearly impossible to purchase an off the shelf AP system.. My boat being 13.5 ton and tiller steered.. Even the largest tiller pilot system comes up short. Good luck. -- My opinion and experience. FWIW Steve s/v Good Intentions |
#4
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Question on autopilot
On Fri, 23 Jan 2004 09:11:40 -0800, "Steve" wrote:
I would recommend staying away from the current generation since the control head don't necassarily have the course computer in them, just some secondary circuits, display and buttons. The course computer is incorporated in some other nav station equipment.. The current ST4000 has the course computer in the head. It comes with a fluxgate compass in a separate housing and the display gives you a compass even if you aren't using the pilot. It is also a Seatalk display if you have a sender for other info. Rodney Myrvaagnes NYC J36 Gjo/a "Curse thee, thou quadrant. No longer will I guide my earthly way by thee." Capt. Ahab |
#6
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Question on autopilot
Daniele,
I may have a solution for you, provided you know a bit about electronics and can handle a soldering iron. The autopilot in my Nicholson 39 was also the old NECO with the drive under the wheel. I have replaced the autopilot by a Robertson AP200, but I left the old NECO drive in place, because replacing it by a new drive suited for a modern autopilot would require a lot of mechanical engineering work plus additional costs for a new drive. I am sure you recognise this. The problem is that the NECO drive is driven by heavy relais and exotic windings in both the motor and clutch, requiring special drive electrics. There is no possibility to have the drive controlled directly by a modern autopilot. The solution is to completely remove all electronics (relais, rudder-feedback potmeter etc) from the drive and replace it by a new electronic circuit, acting as interface between your new autopilot and the drive motor and clutch. I have done this and it works now like a dream. I got the electronic schematics and print layout from somebody here in Holland, and with some minor modifications I got it up and running. The circuit board with electronics fits nicely in the space where the relais were sitting. However, the person from which I received the schematics (the designer) is the owner of the design and I need his approval of course to pass it to others. I can ask him for his permission if you are interested in this. Just let me know if you are. If there are other readers of this message also interested in this specific NECO subject they are of course also welcome to react. If you want to reply directly please locate the email address on my website via the menubar at the top. Regards, /Ger Rietman www.sailsoft.nl PS: Daniele, is it possible that I sent you the Neco user manual a few years ago? "Daniel" schreef in bericht ... In my 1978 Swan 411 there is an old NECO autopilot. I recently fixed some minor faulty circuitry and it now works as it is supposed to do. Too bad that it is a vintage device and, for example, does not have a NMEA input, the course is set on an absolute 360 deg dial and there is no whatsoever display that gives information on the set/actual course. I would like to upgrade it but the 12Volt/20A servomotor under the steering wheel works well and I would like to keep it: it is presently controlled by two relais'. Also the clutch works and there is a rudder feedback, probably a variable resistor, in the same assembly. Keeping them would reduce the cost by a relevant amount and, in particular, would almost zero the mechanical adapting of the steering system. On the market there are many display/control units available with all the modern facilities; using one of them should not be impossible. The main problems I foresee a i) compatibility between the output of the new unit and the relais/servomotor, and ii) possible installation of a new rudder feedback unit. Has anybody in the NG faced those problems and solved them? Daniel |
#7
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Question on autopilot
For people interested: I have placed a picture of the solution he
http://test.sailsoft.nl/neco/AP-Neco-drive.jpg Rgds, /Ger Rietman www.sailsoft.nl "Ger" schreef in bericht ... Daniele, I may have a solution for you, provided you know a bit about electronics and can handle a soldering iron. The autopilot in my Nicholson 39 was also the old NECO with the drive under the wheel. I have replaced the autopilot by a Robertson AP200, but I left the old NECO drive in place, because replacing it by a new drive suited for a modern autopilot would require a lot of mechanical engineering work plus additional costs for a new drive. I am sure you recognise this. The problem is that the NECO drive is driven by heavy relais and exotic windings in both the motor and clutch, requiring special drive electrics. There is no possibility to have the drive controlled directly by a modern autopilot. The solution is to completely remove all electronics (relais, rudder-feedback potmeter etc) from the drive and replace it by a new electronic circuit, acting as interface between your new autopilot and the drive motor and clutch. I have done this and it works now like a dream. I got the electronic schematics and print layout from somebody here in Holland, and with some minor modifications I got it up and running. The circuit board with electronics fits nicely in the space where the relais were sitting. However, the person from which I received the schematics (the designer) is the owner of the design and I need his approval of course to pass it to others. I can ask him for his permission if you are interested in this. Just let me know if you are. If there are other readers of this message also interested in this specific NECO subject they are of course also welcome to react. If you want to reply directly please locate the email address on my website via the menubar at the top. Regards, /Ger Rietman www.sailsoft.nl PS: Daniele, is it possible that I sent you the Neco user manual a few years ago? "Daniel" schreef in bericht ... In my 1978 Swan 411 there is an old NECO autopilot. I recently fixed some minor faulty circuitry and it now works as it is supposed to do. Too bad that it is a vintage device and, for example, does not have a NMEA input, the course is set on an absolute 360 deg dial and there is no whatsoever display that gives information on the set/actual course. I would like to upgrade it but the 12Volt/20A servomotor under the steering wheel works well and I would like to keep it: it is presently controlled by two relais'. Also the clutch works and there is a rudder feedback, probably a variable resistor, in the same assembly. Keeping them would reduce the cost by a relevant amount and, in particular, would almost zero the mechanical adapting of the steering system. On the market there are many display/control units available with all the modern facilities; using one of them should not be impossible. The main problems I foresee a i) compatibility between the output of the new unit and the relais/servomotor, and ii) possible installation of a new rudder feedback unit. Has anybody in the NG faced those problems and solved them? Daniel |
#8
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Question on autopilot
The ST4000 does not require rudder feedback.
"Philip" wrote in message ... Steve, I'm in the same situation as you, in that I have just sold my pre-NMEA AH3000 control head, with the intention of buying an ST3000 control head. I've had two good prices on buying just the control head as I am keeping the drive motor. Most companies want you to buy the complete system. Raymarine (UK) have confirmed that the ST will directly replace the AH but with the added facility of Seatalk. I have the interface from my previous boat, so will be able to marry both parts of the system into my GPS. I was intending to upgrade to an ST4000, but believe that I would have to install rudder feedback, as well as buying a fluxgate compass unit to feed the 4000. With just replacing the AH3000 with the ST3000, that will be all there is to it. regards, Philip, s/v Oyster "Steve" wrote in message ... I'm in about the same situation, having a pre-ST autohelm 3000 that is under powered and doesn't take NMEA input. Otherwise it works fine in calm water with the course set manually.. I have already found a solution to the increase in power, however I'm still searching for an upgrade to the control head. Be advised that none of the pre ST autohelm/Raymarine pilot will except NMEA input.. Even the Z80 interface seems to dislike the current 0183 formats. Then we get into the ST models. Even some of these early ST models still required an interface to convert the NMEA to SeaTalk before it goes to the AP.. I investigated a ST5000 on ebay that had a location for the NMEA connection and the markings were molded into the case, but the connector pins holes were empty.. Must have been a very early release.. Then there is the problem of your drive motor clutch.. I believe that the ST5000 is the first model to have a clutch control in the control head.. Here again, I would approach this with caution since there are going to be control heads sold for tiller pilots that don't require a clutch release. I would recommend staying away from the current generation since the control head don't necassarily have the course computer in them, just some secondary circuits, display and buttons. The course computer is incorporated in some other nav station equipment.. I think your approach is correct as you have evaluated each of the system components and determined what to keep and what to abandon.. Your boat size, like mine make it nearly impossible to purchase an off the shelf AP system.. My boat being 13.5 ton and tiller steered.. Even the largest tiller pilot system comes up short. Good luck. -- My opinion and experience. FWIW Steve s/v Good Intentions |
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