RichJohnson

So I have been buying the Sheridan DMD11 mfus to use in my builds now since ibu2 is gone.
If you followed my leopard 1 build thread you have seen them there. I decided to use the sheridan dmd first since it was the first and only one and I have it in 3 leopard 1 tanks completed or under construciton and I hace a new Centurion DMD 11 in the Belgain leoaprd1.
The Centurion drives much better. The driving algorithm is different and less squirrely in turns especially at higher speeds so I will continue to use those as needed, but they aint cheap to get all the dedicated cables and such needed for the whole system to work.

I discovered this week, that no matter which DMD11 I am testing with the head light and tail light harness from Tamiya, all of them LED "B" does not light up.
Thats 3 sheridan DMDs and 1 Centurion DMD and 4 different LED hedlight taill light wiring harnesses, none of them light up LED "B"

I find it strange that Tamiya would have a failure like this with their electronics and that it would exist on both the Sheridan and Centurion DMD 11 variants.

This does lead toward my assumption that they are all the same DMD with just different firmware loaded into them before packaging and shipping to Tamiya from the Electronics mfr.

Its just odd that they all passed QC and that Tamiya would sell faulty DMD units. These are units I have bought a few years ago up to this month so its not just one run, the first Sheridan DMD 11 units are from when that Tanks spare parts first became available long before the Centurion was even announced.

Any way thought I would share this discovery and see if anybody else has noticed this on their tank or a spare parts unit. So far the people I have talked to with kit built tanks have full sets of working lights.

Its interesting that as of right now my anecdotal evidence suggests its only the spare parts and not kit DMD11s.

Sorry I cant post pictures from home because this forum is still messed up and buggy.

cleong

It appears that LED B will only activate in “control” mode. I don’t have a Sheridan but I imagine it’s similar to the Leopard 2 having different lighting circuits in use depending whether it is in “normal” or “combat” modes.

I’ve attached the manual and translated copy below.

RichJohnson

Well that is interesting and opens a whole new can of worms.
First, where did you find a manual with english? I have the manual I downloaded from TAmiya USA and it does not have english.
Second, what is control mode? Is there anything special about it? Why would it only light LED B in control mode?

So, to operate the lights they have you slide the trim over and tap the stick. I am using a Spektrum DX8 and if I slide the digital trim over the turret just starts turning on its own and tapping the stick does nothing except change the turret speed while turning.
I set up an auxilliary switch to perform the action by making the switch move from center to one side is equal to turret stick to 125% right to turn the head lights and A on and center the other way is turret stick left 125% to turn the spot light on. This works on all the DMD11 units I have but, I have not encountered B turning on at all cycling through the lighting. It would seem that when the tank is turned on it is in Day mode, flip the switch to the side and back and its in night mode. Flipping the switch again turns the lights all back off.
I would guess that flipping the switch again would then enter control mode?, whatever that is and light up B but, so far in my testing I have not experienced that.
I recall that it has just turned the lights back on into night mode again. I will have to test it again to see. Maybe rapid movement is necessary to go right into night mode and right into control mode without pausing...

The next question, does the centurion work the same way with this control mode? There is no section at all in the centurion manual about lights and mode as it does not come with lights. I do know that the lights work, I currently have a centurion dmd11 in the belgain Leopard 1BE I am building.

Have you or anyone made this control mode work and what does it do?

cleong

There isn’t a manual in English; I just simply downloaded that page and had it translated with an app on my phone. Given the quirks of each language, translators don’t typically capture context and nuance, so I take it that “control” is like battle mode for the Leopard. So for that table, I’d read the first column as being “all lights off”, second column as “normal lights” and third column as being “convoy lights” given it is only a single rear lamp (that elusive LED B).

Tamiya is also well known for being funky with servo throws (all those guys who can’t take their Pershings out of neutral at first), so you might want to take the transmitter out of the equation and try using the DMD’s own control and LCD to cycle through the modes. I’ll post a photo later as an update if I can get to my tank, but it is Monday morning after all.

Edit: I take that back, seems you can’t override the settings on the unit itself like you can on the DMD T-07

RichJohnson

So I tried to get into the 3d mode using my toggle switch set up on my DX8. I am unable to get a 3d response other than lights on, lights back off (B excluded) Even when I try to flick it quickly and try to get that 3d mode whatever it is.
I find it curious that Tamiya would even do this with a 3d mode for one light bulb.
I might just cut the LED off 6 inches back and solder it to A and use them as dual tail lights in my Leopard builds.

I wondered if that B could be a convoy light of some type, on US vehicles from WWII through the 1970s the right tail light was inactive in normal driving mode until you either went into black out mode for convoys, or unless you used the "Park" Feature on the 3 lever light switch then a little white rectangular light on the upper right lights up. I have a couple antique army vehicles so I know how they operate and how they differ from the modern full dual tail light setup Humvees and trucks I drove in the Army now use. Similar, but different.

cleong

So I plugged in the hull lighting harness:

A, B, C & D

Keep in mind I have set up my left stick on my DX6 to handle turret functions, and full endpoint over-throws are enabled here for both axis, thus full turret right, which gives you your normal lights, works to turn on LED A, C and D. If you wanted LED B to turn on, it will be full turret left plus main gun fire. There won't be a situation where you can turn on all 4 LEDs, at least not from my short experimentation.

RichJohnson

I went full screen for the video but it looked like you had all 4 lights lit up at a couple points.

cleong

it’s probably lens flare but no I didn’t see all 4 light up at the same time in person

RichJohnson

Ok, really strange operation that it takes gun fire and stick full over to make that one light light up, I still wonder what the heck that is for lol

cleong

Tamiya (sometimes) does things in mysterious ways. I chased down your observation because I remember I noticed the same when I first got the lighting harness and tested it. But with this discovery I guess it just gives an additional lighting circuit option if you wanted to get creative with the lights you wanted to run in the future.

RichJohnson

I tried and tried but I could not get the single B led to light. Oh well, I don’t really need it any way.