Darkith DBU/DBC any good?

[wibblywobbly]

Well its all sorted and back together again now. The sensors and led's are almost out of sight, and everything works as nature intended. The Bulldog was a challenge in this respect.

The problem was down to a very rare break in the pcb circuit between two capacitors, that I found with my multimeter. A quick fix was to bridge the gap with a spare piece of component leg, and I had lift off.

Then I set about cutting all of the sensors and led's off. The sensors are hidden in the turret, and the 3mm led's have been replaced with high intensity 5mm ones that are mounted under the turret, almost out of sight.

The IR led has been replaced with a Maplins YH70M. This is also 5mm and pops straight into the mantle where the HL one was.

It's all looking very neat and tidy now, I have tested it against my Elmod Tiger, a Tamiya Leopard, and a Tamiya Jagdpanther, and it works perfectly.

One thing I like about the Darkith kit is the way that the jumpers for the tank weight are so easily accessible, and the configuration that can be done from the tx. In light tank mode my £130 Bulldog can destroy a £1000 Leopard, which is most satisfying.

A few points to note about the kit though:

You can only record 2 sounds onto the sound chip. Hit and Destroy.
If you have recoil enabled then these two sounds are functional, plus you get the standard HL Fire sound.
If you disable recoil then you can replace the Destroy sound with a Fire sound, in which case the HL Fire sound is bypassed.
If you have a muzzle flash wired into the HL board, then it won't work if you disable recoil as they share the same circuit. This means that if you have a muzzle flash and want to keep it, then you cannot disable the recoil, and you cannot use a custom Fire sound.

All in all it's a very neat bit of kit. If you do not have any soldering skills then I would not recommend it as there are some very delicate bits and pieces to solder. A good quality iron (15w is recommended - though I used a 12w) is essential, preferably with a pointed tip. I also used flux on all joins so that the solder flowed neatly.

Before starting get hold of around 12" of just about every colour of wire that you can find. None is supplied in the kit and you need to colour code several circuits to ensure that you don't blow anything.

I would also recommend getting hold of a cheap multimeter from B&Q, about £5, and use it as a continuity tester. After assembly just trace the circuit between each component to ensure that your soldering has done its job. The good news is that even if you wrecked a component (which is unlikely), they are all available for pennies at Maplins etc.

There are no stand off mounting holes in the boards, or anywhere to drill holes. I used a dab of hot glue on two corners of each board.
The sound board requires you to connect a 6v power source, with the board removed from the tank. Do this before installation. Sounds are recorded by playing them at high volume between two pc speakers while you hold down a record button. This takes some practice! You will also need to connect an HL speaker to the board during this process, so remove it from the tank.

I didn't take any of the DBU as it is a mess of hot glue and wires absolutely everywhere, but these are the ones showing the DBC board, and the hidden sensors on the re-assembled Bulldog. The side ones are replacing two of the periscopes (?) on the side of the turret. They are going to be oversize, but there is nowhere else to put them?

Cheers

Rob G

[The Blitz]

You need a jumper at R-1 or you IR shot LED is not going to work!

[grompix]

Thanks Rob. That's a useful lot of information. Just itching for my DBC/DBU to turn up now!

Cheers
Chris 

[wibblywobbly]

You need a jumper at R-1 or you IR shot LED is not going to work!

The pics were taken before the jumper was put in place, so that I could test each function as I went along. It was inserting the jumper that blew the IR led, hence I knew which circuit had the problem. This comes from a career in testing IT systems, if something doesn't work, it helps to be able to tell the developer the precise nature of the fault. When I gave David at Darkith my problem he was able to confirm that the break in the pcb between the capacitors would cause a grounding problem and blow the led. Hence, when I fixed the break and put in a new led, it worked perfectly.

The new led is a lot more powerful than the original, and I need to fit a 10mm tube over it. It currently hits almost anything in the same room, even a tank that is behind mine! 

Rob G

[The Blitz]

Yes I too have over 20 years in Engineering, R & D and prototype to production build, but more important, I have built over 100 of these DBC/ DBU kits! As you know installing the more powwerful LED into the tub may not be enough, you still may need some resistance, from what I have experienced or you are going to be a friendly fire Nightmere