DM-K1.6 bypass / replace?

AshSplash

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Dec 7, 2015
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Hey everyone,


Soo, I've picked up a set of lights to use externally (internal plug obv) however they'll be plugged in inside the garage. My plan was to plug them into a normal "timer plug" (the plugs with the mechanical wheel that allows to you to supply power based on the time. i.e morning and evening).


However they default to crazy demo mode which isn't really the vibe I'm going for! I promptly took a pair of cutters to the wires going in and out of the controller and connected them back together (minus the controller) I then instantly realised that would never have worked as only half the leds came on. I'm assuming half of the lights are reversed polarity.


So I figured I'd need to still use the controller and looking only seemed like a simple job of bypassing the thyristors. Sadly after opening it up the circuitry wasn't like any of the examples I'd seen. It only has 2 wires and and 2 wires out (so can't bypass). The control does have an "always on" option so I'm guessing it basically flickers power between the 2 so fast you can't see it.

From what I've read I don't think it's going to be possible to use the controller. So, I'm wondering if there's some way I can "make my own" I'm comfortable soldering circuits so am thinking I'd need some components to reproduce the flicking the power both ways (basically making it AC again I guess?).

I've attached a pick of the controller board just in case it helps and also the DC adaptor.

Thanks for your help!




 

David_AVD

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I'm guessing (by the images) that this is a 2-wire LED string. The MFC on these can not be easily bypassed.
 

AshSplash

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Yeah that's what I was thinking. I'm tempted to pick up a Pi Zero to act as the controller instead.
 

thedoctor903

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Jan 11, 2016
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Hello,
I have also picked up some lights with what appears to be the same controller which lacks the ability to recall the last setting after power loss - something that may be useful for OP and I. :) However, I have another set from the previous year with the same controller and it does hold memory.

Here are 2 pictures - The white one holds the memory, the green does not.
https://drive.google.com/open?id=0ByyR4f81A5P9QUdCQ1FKZlE2cTQ
https://drive.google.com/open?id=0ByyR4f81A5P9cGRydGNNbWRPajQ

It would be great if someone could compare the two controllers to see if it's possible to enable a memory function as I have had no success.
The only difference I could see was at R2 on the board and I tried to modify it to be the same but it didn't seem to work.
 

AAH

I love blinky lights :)
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The value of C1 might be the issue as well. There's no markings on it and for the same sized package you can get a many thousands to 1 variation in value. Before swapping the IC I would try swapping that capacitor. Can you make out any markings on the IC?
 

thedoctor903

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Wow fast responses haha.
Nope, can't see any markings on IC or C1.
I should point out that I only have a tiny bit of experience with electronics and with soldering however I will have a shot if you think it's worth it.
If I swap the capacitors to test should I add the resistor at r2?
I can also test some points with a multimeter if it will help just tell me which setting and where :)
 

AAH

I love blinky lights :)
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Before doing any mods I would take a measurement across the capacitor on the 2 boards. Power them both up. Take a measurement. Power off. Measure again over 1,2, 12 hrs to see if there is any noticable difference.
 

thedoctor903

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Just measured the capacitor on both while powered.
Memory controller (white) - 5.25v
No Memory (green) - 5.13v
AAH said:
Measure again over 1,2, 12 hrs to see if there is any noticable difference.
Do you mean after the initial power up and should be powered off for the following tests?
If so, I noticed when I measure the voltage while powered off the power is drained while measuring.
 

AAH

I love blinky lights :)
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Yeah. I was interested to know whether 1 of them maintains a voltage for a long time or whether they both discharge fairly fast and consistently.
 

thedoctor903

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Ok. I measured both powered off.
The white one drops in power and then jumps up again. Eg. may drop to 0.02v then will jump to 0.2 and start going down again before jumping up again. EDIT: After it jumps a few times it stops and then slowly goes down to <0.005
The green one just seems to decrease, very slowly - the minimum I got it too was 0.007v
I will retest tomorrow as you said (12 hours)
 

thedoctor903

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So I tested the controllers this morning and the green one showed a voltage of 0.004v if I'm reading it correctly.
The white controller had 0.001 and flickered to 0 every so often.
Would it be worth swapping the capacitor?
 

AAH

I love blinky lights :)
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I can't see that any logic would retain it's memory at a voltage that low so I'm thinking that the capacitor isn't what is keeping the memory. Is there anything on the other side of the pcb?
 

thedoctor903

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AAH said:
Is there anything on the other side of the pcb?
Just two wires which can be seen in the below image and the connections to the in/out wires
https://drive.google.com/open?id=0ByyR4f81A5P9cG4tREFGSDA2LWc
i13 said:
Interesting. The controller in the video was different, do you believe a similar thing could work for this controller?
Would something like http://www.ebay.com/itm/5-pcs-IC-24C02-FT24C02A-SOP-8-pin-/140769601480? be any use?
 
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