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Logitech Cordless Ball Mouse

Top
Top

This is an old legacy wireless mouse from Logitech. This uses a ball rather than optical technology.

Bottom
Bottom

Bottom of the mouse, showing the battery cover & the mouse ball.

PCB Bottom
PCB Bottom

Top removed from the mouse, showing the PCB inside. The smaller PCB on the left supports the microswitches for the buttons & mouse wheel.

Switches
Switches

Closeup of small PCB showing the microswitches & the IR LED & phototransistor pair for the mouse wheel encoder.

Main PCB
Main PCB

View of main PCB, with interface IC lower right. Pair of quartz crystals provide clocking for the transmitter & internal µC.
Battery contacts are on lower left of the PCB. At the top are the IR pairs for the X & Y axis of the mouse ball.

Encoder Pairs
Encoder Pairs

Closeup of the pairs of IR LEDs & phototransistors that make up the encoders for X/Y movement of the mouse, together with the slotted wheels in the mouse base that rotate with the ball. Steel wire around the smaller PCB is the antenna.

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Marmitek Gigavideo 30

Antenna
Antenna

Here is a Marmitek Gigavideo 30 2.4GHz wireless video transmitter, has a receiver paired which will be uploaded shortly. Here is a view of the antennae, the large flat one being the 2.4GHz directional, the whip antenna possibly performing IR relay functions for the remote control.

Bottom Label
Bottom Label

For all those interested, here’s the bottom label.

PCB Top
PCB Top

The top cover removed reveals the main PCB. Big metal can is the RF transmitter circuitry. was encapsulated circuitry below that looks like an FM modulator for the whip antenna. Big TO220 package on heatsink is a LM7805 5-Volt regulator for the transmitter module.

These units work fantastically well when the antennas are aligned properly, at a decent range, however, they do have a nasty habit of doubling as a very effective WiFi LAN jammer.

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Current Cost ‘Envi’ CC128 Power Meter

Display Unit
Display Unit

This is the Current Cost CC128 Real Time Power Meter. Shown here is the display unit, British Gas issued these free to some customers.
This unit measures current power draw in Watts, cost of power currently being used (requires unit price to be set), overall kWh usage over the past 1, 7 or 30 days & power trends during the day, night & evening. Also displays current time & current room temperature.

Display PCB
Display PCB

Here the front panel of the display has been un-clipped. At the bottom are the RJ-45 serial port & power connections.
This unit uses a PIC micro-controller as it’s CPU (PIC18F85J90) Just above & left of the CPU is the 433MHz SPD radio receiver module. The chips on the right of the CPU are a 25LC128 SPI serial EEPROM for data storage & a 74HC4060 14 stage binary counter, to which is connected the 32kHz clock crystal. The red wire around the top of the display is the antenna for the radio receiver.

For more info on the CC128 in general, the serial port & software for computer data logging, see this link
See this link for Current Cost’s list of software

Processor & Radio
Processor & Radio

Closeup of the ICs on the mainboard.

Transmitter Unit
Transmitter Unit

Here we have the transmitter unit, with Current Transformer (CT). The red clamp fits around one of the electric meter tails & read the current going to the various circuits. This unit is powered by 2x D cells, rated at a life of 7 years.

Transmitter PCB
Transmitter PCB

The PCB inside the transmitter. Again very minimal design, unknown controller IC, 433MHz radio transmitter on right hand side with wire antenna. Two barrel connectors on left hand side of board allow connection of up to two more CT clamps for measurement of 3-phase power. Centre of board is unmarked header. (ICSP?)

Current Transformer
Current Transformer

CT unit. Inside is a coil of wire & an iron core which surrounds the cable to be measured.