Simplified rewiring of HL Part 1

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wibblywobbly
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Simplified rewiring of HL Part 1

Post by wibblywobbly »

Part 1 (please read in order)

There are a lot of people out there who don't understand wires, what they do, or where they go, so seeing as I am rebuilding a Bulldog and setting it up to run either an RX18 or any of the Clark, or Elmod boards, I thought I would take a few pics and show you how I do it.

Please note, this method is designed for basic tanks and will only work if you are not using airsoft.
I am not using recoil on this one, it was an airsoft tank that didn't have a recoil unit.
I have not used an IBU, if it uses the HL IR circuit then you will need to keep the original wiring.

First of all cut all of the wiring out, but leave the turret rotation attached and long lengths on the elevation motor.

The elevation motor may have three wires attached. This is a shared circuit. You only need two, one to each contact on the motor.
DSCN0171.JPG
The wiring inside the hull is always a jumble.
DSCN0172.JPG
The key item is this 8 pin connector.
Always refer to it with the cut-outs facing you.
DSCN0173.JPG
The turret rotation motor has two wires coming off it.
DSCN0174.JPG
DSCN0175.JPG
The 8 pin plug. Yours may or may not have the two pin socket attached.
DSCN0176.JPG
The turret rotation motor goes to pins 1 & 2 on the 8 pin socket. These stay where they are.
DSCN0177.JPG
Pin 3 on the 8 pin socket is the negative for the elevation.
DSCN0178.JPG
DSCN0179.JPG
Pin 4 on the 8 pin socket is the negative for the airsoft
Pin 5 on the 8 pin socket is the positive that is shared by the airsoft and the elevation.
DSCN0181.JPG
Continued in Part 2
Last edited by wibblywobbly on Sat Dec 06, 2014 9:57 pm, edited 1 time in total.
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Re: Simplified rewiring of HL Part 2

Post by wibblywobbly »

Part 2

The original elevation wiring goes through the little board.
DSCN0182.JPG
Cut all three wires off that side of the board.
DSCN0183.JPG
You are now left with three wires attached to pins 6, 7 & 8
These are for the lights and machine gun.
If you have no lights or machine gun, cut them off.
If you are rewiring lights and machine gun then I will show you what the wires do and where they go later.
DSCN0184.JPG
I cut mine off for now as if I fit lights I will do a simplified bit of wiring.
DSCN0185.JPG
The small board is now not attached to anything and can be removed.
DSCN0186.JPG
There are now only 4 wires attached to the 8 pin socket.
DSCN0187.JPG
Always desolder unused wiring. If the insulation comes off then a short circuit will occur when bare wires touch.
DSCN0188.JPG
When connecting wires it is a good idea to use block connectors as a temporary connection. If you find that a motor is going the wrong way when you test it, it is easy to swap them over, prior to soldering.
DSCN0189.JPG
Continued in Part 3
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Re: Simplified rewiring of HL Part 3

Post by wibblywobbly »

Part 3

A simple screw type block connector.
DSCN0190.JPG
Before inserting the wire into the connector, strip back a little insulation, and bend the inner core back over the insulation on the wire. This gives a better grip when you tighten the screw. You don't want wires falling out and shorting something when the power is switched on.
DSCN0191.JPG
DSCN0192.JPG
Lights:

The HL wiring is dodgy to say the least. Bare solder is not a good idea.
DSCN0193.JPG
An LED has a positive and a negative leg. The longest leg is always the positive one.
DSCN0194.JPG
They share a power supply, so the positive legs are joined, and so are the negatives.
DSCN0195.JPG
This is a bit clearer.
DSCN0196.JPG
I will rewire these so that I don't get any magic smoke.
DSCN0197.JPG
Part 4 will cover the RX18, I am off to bed now. Zzzzz....
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Re: Simplified rewiring of HL Part 1

Post by palepainter »

Thanks for breaking this down like this. I am sure it will help a lot of new guys out. It certainly was something I could have used last winter. :)
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Re: Simplified rewiring of HL Part 1

Post by wibblywobbly »

I thought it might help a few people, and as I was doing the job anyway I am just taking pics as I go along.

I have done the lights wiring even though I didn't want lights. lol.

There will be a break in the thread, talk about problems...

I tested one of my HL power switches for continuity...no beep...must be a duff switch?
Tried another and got a beep out of it, ok, good to use.
I pulled out my old batteries , and put one on charge. Left it 30 minutes and thought that it would have enough juice to power the board. Checked it with my my multimeter, and it said 11v?? and kept climbing...and climbing? 12v ..? Hmmmm...

Tried another battery, and it did the same, and another? These batteries have been left unused and uncharged for 12 months, but Nimh batteries should be ok. If the batteries were playing up it would less volts not more. :crazy:

So, I soldered up the switch, and tested the continuity from the battery to the plug that goes into the RX18. It beeped, so good to go.

Plugged it in and the lights flashed, so all good. Unplugged the battery.

Then I tried it again with a different battery, no continuity.

I then tested the multimeter on 1.5v and 3v batteries...they were reading double the voltage. Hmmm.

Then the while testing the continuity again the multimeter made a dying beep noise and the readout went blank.

There was nothing wrong with the batteries, the switch or my soldering, it was the damned battery in the multimeter expiring that was giving false readouts. I spent hours trying to solve problems that didn't exist! :/

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Re: Simplified rewiring of HL Part 1

Post by ALPHA »

Can you do one for IR ? :haha:

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Re: Simplified rewiring of HL Part 1

Post by wibblywobbly »

ALPHA wrote:Can you do one for IR ? :haha:

ALPHA
?? In what way, you need to be more precise. Yes of course this will be IR, that's why I am rewiring it. All systems are IR, it is only the board that determines which IR system it is, eg HL or Normal. The HL IR will function as per normal as it doesn't run off the 8 pin socket. Aftermarket boards use the 8 pin socket to run the lights and turret controls, and have seperate sockets for the IR led, and apple.
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Re: Simplified rewiring of HL Part 1

Post by wibblywobbly »

Part 4

Ok, back on track. First thing to mention is that the front headlight led is blown, I mentioned the high risk bare led legs earlier, and it looks like they have indeed shorted out at some point in the life of the tank. I tested the wiring with another led and it was working. I therefore cut the wiring to the duff one, and taped the wires to the hull. The circuit is ok, so if I want to mount a spotlight on the turret roof or anything, the wires are already there.

I will also quickly mention that the 2 pin socket that you may have on the side of the 8 pin socket is for the machine gun. A machine gun is simply an led that is fed by a pulsed feed that makes the led flash. So, if you have an led and a 2 pin socket you can pop it in there using a 2 pin plug and it will work.

If you do not have a 2 pin socket to use, then simply solder the live wire to the same one that the lights use, and the negative wire to the last (empty) contact on the 8 pin socket.

Back to the RX18 plugs:

The motors plug in next to the power plug. One little tip is to twist the wires rather than leave them straight. The motor wires generate pulses that contribute to interference. By twisting them the pulses in one wire cancel out the pulses in the other.
DSCN0198.JPG
The power switch. These are usually 3 pole switches with wiring attached by HL in a weird and wonderful way that confuses the hell out of anyone fitting a new one. The reason that they do this is because there are capacitors on the board. Capacitor store electricity ( I won't bore you with why). When the tank is turned on the voltage stored in the capacitors could in theory cause the tank to jump about. The on off switch is therefore prewired so that when the tank is switched on it drains the capacitors and prevents that happening.

All of which can be safely ignored.
Get all of the old solder off the switch so that you are left with 6 pins.
You will only use 4 of them.
Take the red and black wire from the battery, and solder them to the middle pair of pins on the switch.
Ensure that no solder bridges the pins.
Take the red and black wire from the HL power lead, and solder them to an end pair of pins.
You should have two red on one side and two black on the other.
If you are feeling clever, you can now solder a female battery socket to the unused pins, and mount it somewhere.
When the switch is pushed off, the circuit to the tank is closed, the extra socket is open, but the battery connection is still live (its not doing anything because at this point the switch is no longer activating the circuit to the tank). You can now charge the battery without taking it out of the tank, by plugging the charger into the extra socket.

Redundant way, better pics of the revised power switch wiring appear further down.
DSCN0199.JPG
This is where the HL IR wiring plugs in. If you are using an aftermarket board you can usually dispense with this.
DSCN0201.JPG
This is the volume control. It is a cheap potentiometer, that does nothing for the sound. Most people run their tanks at full volume, so I will show you how to dispense with the volume control altogether and have permanent full volume later on.
DSCN0202.JPG
The speaker plugs into the end socket on the top row. This is just a bare plug to show you where it goes.
DSCN0203.JPG
The smoke unit switch goes here, though most people bin the smoke unit and the switch.
DSCN0204.JPG
This is the 8 pin lead that connects the RX18 to the 8 pin socket in the hull.
DSCN0205.JPG
This is the receiver wire, it connects the RX18 to the reciever board.
DSCN0207.JPG
That's all of the RX18 sockets covered.

More in Part 5.... :thumbup:
Attachments
DSCN0208.JPG
DSCN0206.JPG
Last edited by wibblywobbly on Fri Jan 09, 2015 9:04 pm, edited 1 time in total.
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Re: Simplified rewiring of HL Part 1

Post by wibblywobbly »

Part 5...

The 8 pin connector connects the lower hull to the upper hull.
DSCN0208.JPG
If your motors do not have plugs attached, you will need to solder the leads on. I suggest doing a test run with block connectors before soldering, as the polarity may have to be switched to make the motors run the correct way.
DSCN0209.JPG
A better pic of the speaker plugged in.
DSCN0210.JPG
The front headlight shown, with heatshrink over the led legs to stop anything shorting out. In my case I was too late, the damage had already been done. The wiring is attached to the 8 pin socket as described earlier.
DSCN0213.JPG
The rear lights needed sorting too.
DSCN0215.JPG
Sorry about the fuzzy pic. The two led's are joined neg to neg, and pos to pos. Then a lead is taken off anywhere along the neg wire, and another off the pos wire. This is attached the 8 pin socket at the same locations as the front light, eg contact points 6 (pos) & 7 (neg). You cannot blow an led by getting the polarity wrong, either it works when connected the right way, or doesn't if connected the wrong way. You can blow them very easily with excess voltage or by shorting the pins while the circuit is live.
DSCN0216.JPG
Here you can see the front and rear wiring coming together. Cut to length, ensuring that you have sufficient length to reach the 8 pin socket.
DSCN0217.JPG
The ends of each positive wire should be twisted together and dabbed with solder, the same with the negative pair. This makes it easier to solder them onto the socket.
DSCN0218.JPG
Then solder them on to socket.
DSCN0219.JPG
That's the lighting circuits covered, they are quite simple really.

Part 6 to follow....
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Re: Simplified rewiring of HL Part 1

Post by wibblywobbly »

Part 6...I hope.. I am losing count here. lol.

This shows the lighting loom soldered to the 8 pin socket.
You can also see that there is a block connector on the bare wires that relate to the elevation circuit. Using block connectors to cover bare wire ends is a good way to prevent short circuits when testing. It stops bare wires touching anything else or each other.
DSCN0220.JPG
Its a matter of opinion but I think that this looks a lot neater than what HL do. If you rewire a tank it not only tidies everything up, you also learn what goes where and makes fault finding a doddle.
DSCN0221.JPG
The reason for not wiring the elevation motor directly to the 8 pin socket is that the cable needs to pass down through the centre of the turret ring. HL run a wire all the way out and everything is soldered, so you have to remove an entire harness to remove the turret. I install a plug that is attached to the upper hull, so that I can unplug the turret, undo the turret ring, and lift the turret straight off. Always leave enough slack for turret rotation.
DSCN0222.JPG
Another terrible photo, just showing that the lights work when the tank is switched. No need for the transmitter at all to do this.
DSCN0224.JPG
This is the pic I promised showing the revised on/off switch wiring. Battery connected to the center terminals, HL plug to the end two. If you are connecting a charging plug, ensure that you do it this way, with the HL plug connected at one end, and the charging socket at the other. The battery must be connected in the middle.
DSCN0228.JPG
As this will be an IR tank, I am fitting a muzzle flash. So I simply run a pair of wires down the barrel. The led will be connected at one end, I just use high intensity 5v yellow or white, they are a lot less hassle than an HL bit of kit. The led can either be linked to the 8 pin socket ( I think...its a long time since I did that :/ ), or connected to the appropriate socket on an aftermarket board...which is where this one will go. Always leave enough slack to reach the location, and also to allow for turret rotation.
DSCN0229.JPG
Having removed the front headlight connection due to the led being blown, I used a block connector and took the opportunity to go through my unlabelled led's and test them to see what colour and type they were. This is a 5v feed, so don't try 3v led's using this method.
DSCN0230.JPG
That is pretty much it.

If the lights work you know that the power is getting to the board.
Everything else should function when plugged in.

You can use this method of rewiring to convert any non-hl tank. They all use a motor for turret rotation, barrel elevation and have motors to drive the tank, I did a WSN T34 this way, pulled all of the WSN wiring and re-did it as described here, it worked like a charm, and even ran an Elmod system.

If you need circuit diagrams for airsoft, recoil etc there are loads on the web, so I won't bother repeating them all here.

I will add to this when I pull out the RX18 and install an aftermarket board, so that I have an IR battling tank, though that may be a couple of months away as I can't make up my mind which board to go for. :crazy:

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