System Installation @ Monterez

Today, we're installing a new PABX to replace a small keyphone. The reason the customer is upgrading was due to the fact that their old keyphone could not keep up with their staff expansion. They already have 22 extensions, just two short of reaching full capacity, where the system could not be expanded anymore.

One of my techs are installing some cable casings.
You can see the old keyphone system on the right

All done! And the the customer called me over,
"Wei, the (system) is so big la, you said I could
cover it up with a plant?". I replied, "Can, what.
But not my fault if your plant guys took it away
just now. Maybe you could get them to give you
a small jungle instead. Ha ha ha!"

The the customer replied, "Not funny. And your "Ikea" box looked
like crap la. Which I defended, "You know Ikea is DIY stuff and the
"Ko-Tak" (or kotak, which is Malay for box) series is pure DIY. See?
Even the planks we have to cut it to the right size"

Customer was not amused and handed me a brush and some
white paint..... "Make it look nicer, OK? Or you cannot go."

Unfortunately, we have to go back on Monday because our planned Saturday follow-up did not materialise as Tenaga came and handed the customer a flyer telling them there would be no electricity on that day. sigh

315 MHz RF Remote system

While I had some free time, I decided to drop by Pasar Road again. This time, I bought a set of 315MHz RF transmitter and receiver. Why did I do this? On my first paying project a week ago, I used a RF remote to control an electronic device. Then, after that, I decided to go back to another shop to replenish my remote control system. But they're out of stock.

So, it set me to thinking, why not build my own? Already I have bought two versions, the one that was sold uses a single channel while the remaining one I had is a 4-channel version, where both are momentarily. This means, the moment I press on the transmitter button, the relay at the receiver would click and then release. Not only that, I have found the chip needed to make the whole thing work.

The modules I bought are just transmitter and receiver and I need some IC to control the data sent and also, "match" each transmitter with the correct receiver. And depending on the chip, it has two versions, momentarily and latching (the relay will not disconnect until you press the button on the transmitter again)

The transmitter is not going to be a problem if i can buy it separately. As for the actual transmitter module, I can use it on any casing or prop if the ready-built transmitter is not small enough.

On the left is the transmitter, and on the right is the receiver

Here is the transmitter compared with an already built version

And here is the receiver. This is a 4-channel version, as there
are four relays. Look at the circuit on above left and compare
it with the picture of the receiver module above. Yes, they're
the same!