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Dremel MultiPro

Front
Front

Here we have a Dremel MultiPro rotary tool, a main powered 125W 33,000RPM bit of kit.

Motor Assembly
Motor Assembly

Here the field & controller assembly is removed from the casing.

Armature
Armature

Here is the armature, which rotates at up to 33,000RPM. The brushes rise against the commutator on the left, next to the bearing, the cooling fan is on the right hand side on the power output shaft, the chuck attaches at the far right end of the shaft.

Speed Controller & Brush Box
Speed Controller & Brush Box

Here is the speed controller unit, inside is an SCR phase angle speed controller, to vary the speed of the motor from 10,000RPM to the full rated speed of 33,000RPM.

Mains Filter
Mains Filter

This is the mains filter on the input to the unit, stops stray RF from the motor being radiated down the mains cable.

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Ericsson GA628

Front
Front

Here is a phone from the mid 90s, the Ericsson GA628. Here visible is the front of the unit with keypad, & single line monochrome LCD for number display.

Battery & Rear
Battery & Rear

Here the battery is removed from the phone, showing the SIM card socket. At the top under the antenna stub is the socket for an external antenna.

Front Removed
Front Removed

Here the front is removed from the phone, PCB on left, rear of keypad on right. Microphone is at bottom of keypad, with speaker at the top. Top right of the PCB is the ringer buzzer, left is shield for RF amplifier.

Main PCB
Main PCB

Here is the back of the main PCB, RF sections on left & centre. Processing & memory on right.

Battery
Battery

This phone had a Ni-Mh battery, before Li-Ion batteries were introduced.

LCD
LCD

The LCD from the front of the phone is shown here. A simple dot matrix single line unit.