One of the Batteries from my Bosch cordless drill machine had died. I could buy a new one but that is rather expensive. So I opted to take the batteries out and put a cable on it. The cable plugs into my 12V power supply that powers my lights etc.
The cells inside (5 cells at 0V):
I have mounted a cable gland in the plastic enclosure from the old battery so I have a strain releave for the cable.
Plugged in the drill:
I added a diode to the power supply to protect my power supply against voltage spikes from the motor.
The downside of this is of course that I have a cable connected to it now. But I still have 1 battery that functions so I can still work wireless :p. But if I’m working at the workbench and the battery is flat, then I can use the cable to avoid waiting for the charger. Another downside is that my LED lights dim as I start the drill, this is because it draws too much current. The power of the drill isn’t as big as on the battery. My power supply delivers 12V while the battery does 14.4V.
I was using my network more intensely to transfer files the last weeks. And I got tired of waiting, so it was time to update my network. So I ordered a new switch and router from de-computershop.be, and today they arrived :).
My old “fast ethernet” 100Mbit/s equipment:
Linsys WR454GL 4 port router
D-Link DES-1005D 5 port switch
My new “Gigabit” 1000Mbit/s equipment:
Linsys E2000 4 port router
Cisco SD2005-G2 5 port switch
The new gear is working great, the only downside is that you need to install a config program on the pc to config the router. It has a build in web interface, but it doesn’t cover all the settings :s.
This is my entry for the 555 contest. I didn’t have much time to make something so the entry isn’t much.
This design is a fan controller. The base of it is a simple pwm circuit with the 555 timer. The problem with fan’s is that they don’t start at low voltages. So I added a capacitor (C2) to give it a little voltage boost at the startup.
The circuit can also be easily adjusted to have a soft start. This can be useful when driving led’s etc. This way the light is not instantly bright.
Unboxing: The box doesn’t contain much. Only the soldering pot and a chinese manual.
Take it apart:
The next thing to do is to open it up and see if it is safe enough to plug in to the mains.
After cutting the too long wires down to size I decided to take a closer look at the pcb. Then I saw that it was not temperature controlled like the dx site claims. The power to the heater is controlled, but there is no feedback. I made a circuit of it to proof it.
First I have made some good pictures of the pcb:
Then I placed the 2 pictures on top of each other and made the top one transparent:
Now it is easy to derive a circuit diagram from this.
There is not enough space between the pcb and the enclosure, especially because it is made of metal, luckily it is grounded. The wires are cut too long.
The pcb looks like its soldered very good, I didn’t expect this with something this cheap.
Powering It Up:
Tinning Some Wire And PCB:
Temperature Accuracy Test:
I’ve put the thermocouple from my multimeter in it. In the lowest range of the soldering pot it should be arround 200°C and I measure 279°C. If it was really temperature controlled like dx claims then the difference would be too big. Because the power is controlled this could be expected.
It is a pity that it is not really temperature controlled, but for the money you pay for it, it was to be expected. But this doesn’t really makes it work bad. If you use flux or soldering grease then the wires tin very easy.
So I think it is a good buy :). But keep in mind you still need to buy/have enough solder to put in it. You can use normal solder, but then its going to smoke a lot at first.