Wednesday, May 12, 2021

  My articles for the sailing magazine Compass











See also: http://slowfoxsailing.blogspot.com/2021/01/how-to-build-remote-control-into-simrad.html


Tuesday, January 12, 2021

 XT Wind Vane DIY for Hydrovane Selfsteering

 


The Garden Hose Connector (left side) is glued to the outer Pipe at the T junction and locks the inner Pipe to the outer.

See it in operation here: 

https://www.youtube.com/watch?v=YzGR7KUWCyU&t=8s


Monday, January 11, 2021

How to build remote control into a Simrad TP10 Tiller Pilot

Adding wireless remote control to a Simrad TP10 tiller pilot

 

This paper is about how you can buy a 433 MHz readymade transmitter/ receiver kit, put it into the casing of a Simrad TP10 tiller pilot and interface the PCB to gain remote control of the four buttons Port, Starboard, Tack and Standby/Auto. The same modification can be applied to a TP20 or TP30 as well. I will leave it to you to contemplate on the possible advantages of remote operation and instead point out a few possible disadvantages of doing this modification:

 

If you still have a valid guarantee it will be lost the moment you open the casing of the pilot.

A 5 mm hole has to be drilled in the inner PCB case for four wires. Water could enter here.

The RF receiver/relay board will be placed in the outer case. This has a seal but it’s not completely watertight in the push rod end. (However Simrad have them self placed a little Hall Effect board in this section)

You may damage the PCB with your soldering iron.

It is unknown to which extends the RF is susceptible to high frequency noise from other sources.   

 

Although I have no long term experience with these concerns I remain optimistic. Make a raincoat for the pilot. Many ocean cruising people do that.

So if you are still with me let’s get started!

First you have to buy exactly this INSMA radio transmitter/ receiver at Amazon (or elsewhere):

 

 

You'll may find it here:

https://www.amazon.com/INSMA-Wireless-Channel-Receiver-Transmitter/dp/B01CCSG2ZY/ref=pd_rhf_ee_p_img_1?_encoding=UTF8&psc=1&refRID=KQRK9PXDZ98Q9S0B8RR7 

 

Price around 15 £. Yes it’s cheap, but reliable it seems. My own experience with it is limited, but I have checked more than 100 reviews on the net.

 

Prepare yourself with the following tools:

A large and a small screwdriver, both Phillips. A pliers. A multi meter (may not be necessary with this guide at your service). Soldering tin (mine is only Ø1 mm) but use as small a diameter you can find. A 12 volt battery or similar with capacity to deliver 5A for the final test with motor running. You can do with much less for setting up the INSMA kit.  A soldering iron with a small pointed tip and you will need to drill a 4-5 mm hole in the circuit board case. Some (hot) Glue.


1

When the order arrives at your disk open the lid of the white box and remove the 4 screws. You are not going to use any of this. Take a look at the RF receiver-relay unit. 4 relays are just enough as there is no need to "push" the calibrate button. 

 

 

In the left corner of the picture, just beside the LED and push button a small jumper that determines the mode of operation of the relays is located. Pull it off. Now the relay will close its contact (conduct) when you push a button on the key ring transmitter and release when you remove your finger. 

 

2

Use a red wire and blue wire Ø around 1½ - 2 mm outer diameter and length about 20 centimeter and connect 12V to the power terminals. Use red for +. (This is the only red wire you will need in this project. All signaling to the Simrad switches are done with negative). I butchered an old parallel printer cable and got some excellent wires from it. Don't reverse the polarity or you may damage the board. 

Now you have power on and the LED should shine bright.  

3

Paring the transmitters with the receiver (receiver stores the transmitters code in memory): 

 

Take one of the key ring transmitters and press button A shortly. The LED goes dark. Release A. The LED starts flashing 3 times.

Repeat this sequence with the other transmitter.

You can hear that the relay A that I have labeled A with a piece of masking tape in the picture above give a click whenever you press button A. The rest of the relays are located in alphabetical order.

 

4

Ok, now you have some serious wiring to do. So switch off the 12V power supply for now. From the negative (blue wire) power terminal you run a wire to relay A contact B. Yes you have to put two wires in the same terminal. That's why small diameter wires are handy. And the currents involved here are extremely small, so it's not a problem. I will put the next connection of wires in a small table:

 

 Relay  contact B       to           Relay  contact B

 Relay  contact B       to           Relay  contact B

 Relay  contact B       to           Relay  contact B

(All 4 contact terminals C should be left unused)

 

Next you just need to connect the last 4 wires. Make them about 50 centimeter each and of different colors and put them in the contact A terminal of each relay. They are going to enter the holy grail of the tiller pilot and give us what we want. Total control. I have chosen to make button A on the transmitter PORT, button B is STARBOARD, button C is Tack and button D is STBY/AUTO

 

5

It is time to open the tiller pilot! Put it on a towel on your table facing down and with the pushrod to the left. Start unscrewing in the right hand side at number 10 as indicated in the drawing below:

 

 

 

 

Gently turn the pilot back so the push button side is upwards taking care not to lose any screws.

Open the lid slowly. It’s interconnected to the other half where the motor is so you can't remove it entirely.

 

Unscrew the cover of the Circuit Board. The board is loosely fixed to the cover and will follow when you turn it so the push buttons face upwards. You need to twist the bundle of wires gently. 

Place a strip of masking tape around the flux gate compass to protect the little band of wires. 

Drill a hole in the bottom of the case large enough to pass the 4 wires through.

Finally position the receiver unit as best possible keeping it low. There must be space above the relays etc. for the pushrod to travel.

6

And if you are nervous about ruining your TP10 Circuit board now is the proper time to be it.

So before you start attacking the brain of your autopilot let's take a break and look at some "nice to know" knowledge namely, what are we actually doing? How does this work? Later you better pay attention to the "need to know" as well.

Take a look at this section of the schematic:

  

 

Note that all 4 push button switches have a connection to 0V (negative) on the left hand side.

On the right hand side 4 connections leads up to the microprocessor.

A +5V supply will keep all lines at digital High until you press a button thus creating a path to 0V on that particular line. This will quickly be noted by the microprocessor and it will initiate the proper action. The four 10K ohm resistors limits the current to 0,5 mA. So you see why we don't need thick wires!

The contacts in our Relays are just 4 extra switches working in exactly in the same manner as the pushbuttons and you can of curse still use the buttons on the pilot as before. 

 

Now let’s go to "the need to know".

You need to locate the plus side of all switches as this is the connection point for the wires.

It can be easily done with a voltmeter, or you can just look at the drawing below. I have done it already.

I have chosen the points for soldering with the minimum of pads and other components in the vicinity. But don't spill tin on the board anyway.

 

You need to have some soldering experience. But even if you have some, please give it a refreshment now by exercising on something else than your precious tiller pilot. 

 

  

Let me tell you how I did the soldering.

  1. Cut the wire giving it a generous length (see pictures)
    1. Strip 2 mm 
    2. Apply soldering tin until the wire has soaked it. Not more.
    3. Clean the tip of the iron on a wet sponge or a wet cotton cloth to remove old flux and excessive tin.
    4. The board is not clean even if it looks so. So scrape a place as high as possible on the foot of the pushbutton with a pocket knife and clean the place with alcohol.
    5. Put a small amount of tin on the iron and place it on the foot of the pushbutton.
    6. Clean again and apply an absolute minimum of tin to the iron. We only want it to look wet.
    7. Now with one hand hold the wire onto the tin on the button and gently press it with the tip of the iron against the tin on the button. Hold it there for 2 seconds until you see it melts together in a shiny fashion. Take the iron away while holding the wire steady for another 4 seconds.
    8. When you have done all four connections give them a little tug to make sure they are okay.

      I pushed the 4 wires onto the component side of the board, but you can also run them down on the printed side. Just ensure they don't conflict with buttons and led’s and preferable don't cross each other.

      Turn the box and screw it back in place. You are done here now.

      7

      Next you must supply 12V to the receiver. I did it by breaking into the wires of the supply cord. Look at the picture:               

      Take care to find the right 2 wires. Unfortunately there are two pairs of blue and brown wires in the bundle, so take care. Slice a small piece of the insulation off on both wires, with an offset to reduce the risk of a short circuit. Soak the cobber with tin. Strip 3mm off on the wires from the receiver and solder it as previously explained. Brown to brown and blue to blue of course. Put a piece of tape around each. 

      8

      With the pilot casing still open you are now ready for a workshop test run. Or perhaps you should skip this test and just proceed to point 9. 

      If you decide to do the tests please be very careful! There are no fuses inside the pilot. If you reverse polarity a diode will burn. You will need a power supply (battery) capable of 12V 5A.

       

      For your information I have measured the amp´s to be:

       

      Motor not running:              0,5A

      Motor running no load:        1,4A

      Motor running some load:   3A

      Motor blocked at rod end:   4A

       

      If the pilot detects a low voltage situation it will return to standby.

       

       

      9

      If all is well, then arrange the relay board in the best possible manner. (I decided to remove the cable tie to make the bundle more flat).

      Perhaps use a cable tie here and there. Then glue the board to the pilot casing. Perhaps glue some wires too. Close the hole you drilled in the board box earlier. I used hot glue. Use high temperature hot glue if you want to be absolute sure that it will still stick on a hot summer's day.

      Bring the two halves of the pilot together again in the very carefully way described in section 5. 

      The sequence of the screws is now 1 to 10.

       

      Now try it onboard your boat. And enjoy!