Status RCS-K09 Control
There seems to be a lot of variants of these little sockets available, according to this thread on the picaxe forum they seem to have been sold under various brands in the UK by Asda, Morrisons and others, the most frequent seems to have been the "Status" brand. The model numbers seem to be consistently referenced RCT-08 for the transmitter and RCS-K09 for the sockets.
They're a 433mhz controlled socket and come in packs of anything from 1 to 4 with a remote. They're rated for 2900watts and internally, I found them to be using HKE V6 relays with a maximum switching current of 16A @ 250VAC. So they should be good for 2900 watts and a little bit more to spare.
Internally the wiring is pretty good. Earth is a direct connection, with no wires. Neutral is also direct, only Live is switched. Soldering looks solid - they seem unlikely to burn your house down.
Nothing too exciting here, looks quite cheap (through-hole components rather than SMT) and a very basic single layer PCB. Only identifying markings on the board are "RCT-08A-03", mirroring the markings on the back of the case also saying RCT-08.
This one seems to be using a HS1527, which is nice as it means it's likely to be compatible with RCSwitch.
Decoding the RF Protocol
As it's highly likely these will be supported by RCSwitch, we may as well start there. Loading up the "ReceiveDemo_Advanced.pde" sketch and trying out each of the buttons we get these results;
1 On Decimal: 3402623 (24Bit) Binary: 001100111110101101111111 PulseLength: 306 microseconds Protocol: 1 1 Off Decimal: 3402615 (24Bit) Binary: 001100111110101101110111 PulseLength: 307 microseconds Protocol: 1 2 On Decimal: 3402619 (24Bit) Binary: 001100111110101101111011 PulseLength: 307 microseconds Protocol: 1 2 Off Decimal: 3402611 (24Bit) Binary: 001100111110101101110011 PulseLength: 307 microseconds Protocol: 1 3 On Decimal: 3402621 (24Bit) Binary: 001100111110101101111101 PulseLength: 307 microseconds Protocol: 1 3 Off Decimal: 3402613 (24Bit) Binary: 001100111110101101110101 PulseLength: 307 microseconds Protocol: 1 4 On Decimal: 3402622 (24Bit) Binary: 001100111110101101111110 PulseLength: 306 microseconds Protocol: 1 4 Off Decimal: 3402614 (24Bit) Binary: 001100111110101101110110 PulseLength: 307 microseconds Protocol: 1 All Off Decimal: 3402616 (24Bit) Binary: 001100111110101101111000 PulseLength: 307 microseconds Protocol: 1
So using them with an Arduino should be easy as pie.
Refer to the main instructions for RCSwitch for more info.