Old type ionization smoke alarm. Top of the device with the test button & sounder.
Bottom of the device. Battery compartment in centre.
Internals of the smoke alarm. Main component visible is the Ionization chamber.
Piezo sounder on inside of the top.
Inside the Ionization Chamber. 1µCi Americium-241 alpha particle source in the centre.
The radiation passes through the chamber, between the pair of electrodes, ionizing the air & permitting a small current to pass between the electrodes.
Any smoke that enters the chamber absorbs the alpha particles, which reduces the ionization and interrupts this current, setting off the alarm.
An old IDE interface Zip drive. This fits in a standard 3.5″ bay.
Top cover removed from the drive, IDE & power interfaces at the top, in centre is the eject solenoid assembly & the head assembly. Bottom is the spindle drive motor.
Head assembly with the top magnet removed. Voice coil is on the left, with the head preamp IC next to it. Head chips are on the end of the arm inside the parking sleeve on the right. Blue lever is the head lock.
Controller PCB removed from the casing.
Spindle motor. This is a 3-phase DC brushless type motor. Magnetic ring on the top engages with the hub of the Zip disk when insterted into the drive.
Magnets that interact with the voice coil on the head assembly.
Head armature assembly removed from the drive. The arm is supported by a pair of linear bearings & a stainless steel rod.
Here is a cheap no frills microwave oven, which died after a few weeks of normal use.
Cover removed, showing the internals. Front of the microwave is on the left.
Closeup of the timer unit. Cheap & nasty.
Magnetron removed from the oven. Antenna is on the top, cooling fins visible in the center. White conector at the bottom is the filament terminals.
Chokes on the magnetron’s filament connections. These prevent microwave energy from feeding back into the electronics bay through the connections.
Magnetron cooling fins, tube & magnets removed from the frame.
Bare magnetron tube.
This PCB does some rudimentary power conditioning, power resistors are in series with the live feed to the power trasformer, to prevent huge power up surge. When the transformer energizes the relay, which is in parallel with the resistors, switches them out a fraction of a second after, providing full power to the transformer.
Standard RFI choke & capacitor at the top of the board, with the input resistor.
Power transformer to supply the magnetron with high voltage.
Power output is ~2kV at ~0.5A. Pair of spade terminals are the low voltage filament winding.
HV Capacitor. This along with the diode form a voltage doubler, to provide the magnetron with ~4kV DC.
HV diode stack.
Internals of the HV fuse. Rated for ~0.75A at 5kV. The fuse element is barely visible attached to the end of the spring. Connects between the transformer & the capacitor.
Cooling fan for the magnetron. Drive is cheap shaded pole motor.
Here is one of the first USB tuners that was available from Hauppauge Computer Works. Totally analog tuner of course, this model required 2 cables – a USB interface & a sound cable for the audio output of the tuner.
A/V connections.
For those who are interested. Here is the label with the model details.
Connection to an external antenna.
Bottom of the PCB.
Top of the PCB showing the USB interface IC (top left), cache memory (top right) & the main tuner assembly.
Here is a cheap no brand hot laminator. This pulls the paper, inside a plastic pouch through a pair of heated rollers to seal it.
Top removed, heater assembly visible. PCB attached to the top cover holds LEDs to indicate power & ready status.
Here is the thermostat & thermal fuse, the thermostat switching the indicator on the front panel to tell the user when the unit is up to temperature. This has a self regulating thermostat. Thermal fuse inside the heat resistant tubing is to protect against any failure of the heater.
5 RPM motor that turns the rollers through a simple gear system.
Cheap unbranded window break alarm. Here is the front of the unit, with the sounder at the top, Power/sensitivity switch at the right. Battery test button at the left.
Rear of the device, with the adhesive pad used to attach it to a window.
Front cover removed, showing the batteries, PCB & the sounder.
PCB removed from the casing, showing the remaining components.
This is an old CO alarm, which was totally dead, having been connected to the wrong PSU.
Here is the front of the unit, with the Test button & indicator LEDs.
Front of the PCB, 3 1.5v cells powered the unit, Piezo sounder & sensor cell in the centre of the board.
This is the hydraulic system from an Audi TT that would power the soft top. Here is the hydraulic pump unit. Oil Tank is on the left. Power is 12v DC at ~20A
The pair of hydraulic cylinders that attached to the roof mechanism.
One of the cylinders has a limit switch built in. The brass bolt coming out of the side of the head is one contact. The other contact is the cylinder body.
Marking on the hoses. This is Parker Polyflex hydraulic hose. 1/8″ ID.
Drive motor for the hydraulic pump. Standard DC permanent magnet motor.
Motor power terminals & suppression capacitors. As the reversing relays actually short the motor out when de-energized, there is a lot of arcing at the brushes without some suppression.
Reversing relay stack. Each relay is a SPDT configuration. The pair are arranged as a DPDT bank to reverse the motor, depending on which relay is energized.
Detail of the oil tank showing the level markings.
Solenoid valve on top of the unit. This valve provides full pump pressure to the cylinders when energized.
A quick post documenting a DPSS laser module i salvaged from a disco scanner. Estimated output ~80mW
Connection to the 808nm pump diode on the back of the module. There is a protection diode soldered across the diode pins. (Not visible). Note heatsinking of the module.
Driver PCB. This module was originally 240v AC powered, with a transformer mounted on the PCB with a built in rectifier & filter capacitor. I converted it to 5v operation. Emission LED on PCB.
Here’s my prototype 455nm laser head, constructed from the front section of an Aixiz module threaded into a heatsink from an old ATX power supply. This sink has enough thermal mass for short 1W testing.
Connection to the laser diode at the back of the heatsink. Cable is heat shrink covered for strain relief, & hot glued to the sink for extra strain relief.
Looking down the beam, laser is under the camera. Operating around 1.2W here
Camera looking towards the laser. Again operating at ~1.2W output power.
To help make my system more efficient, a pair of switching regulators has been fitted, the one shown above is a Texas Instruments PTN78060 switchmode regulator module, which provides a 7.5v rail from the main 12v battery pack.
A Lot like the LM317 & similar linear regulators, these modules require a single program resistor to set the output voltage, but are much more efficient, around the 94% mark at the settings used here.
The 7.5v rail supplies the LM317 constant current circuit in the laser diode driver subsection. This increases efficiency by taking some voltage drop away from the LM317.
The 7.5v rail also provides power to this Texas Instruments PTH08000 switchmode regulator module, providing the 5v rail for the USB port power.
A quick update to my portable power pack, a mains charging port. Uses a universal DC barrel jack.
Connection to the battery. 1N4001 reverse protection diode under the blue heatshrink tubing. I used a surplus PC CD-ROM audio cable (grey lead). Seen here snaking behind the battery to the DC In Jack.
An early speed radar detector from the early 90’s. Pictures showing the front of the unit with the option buttons.
Bottom of the unit showing label. Unlike the newer plastic detectors, the whole casing of this unit is cast aluminium.
Model Uniden Stalker RD-6000W.
PCB removed from the casing. Volume/power control on the left. Option tactile switches on the edge of the PCB, with the indicator LEDs. Power input jack on the right hand side of the PCB. Large aluminium can is the detector assembly, containing the detector diodes. Waveguide horn is at the top.
Shot down the waveguide, showing the detector diodes at the end.
Indicators on the front of the unit, X, K & Ka band detection LEDs on the left, Power & detection level (1-4) LEDs in centre. City (C) (Audio (A) & Mute (M) LEDs on the right.
Bottom of the PCB, showing detection logic. Piezo buzzer top left.
The parts arrived for my adjustable laser diode driver! Components here are an LM317K with heatsink, 100Ω 10-turn precision potentiometer, 15-turn counting dial & a 7-pin matching plug & socket.
Here is the schematic for the driver circuit. I have used a 7-pin socket for provisions for active cooling of bigger laser diodes. R1 sets the maximum current to the laser diode, while R2 is the power adjustment. This is all fed from the main 12v Ni-Cd pack built into the PSU. The LM317 is set up as a constant current source in this circuit.
Here the power adjust dial & the laser head connector have been installed in the front panel. Power is switched to the driver with the toggle switch to the right of the connector.
The LM317 installed on the rear panel of the PSU with it’s heatsink.
Connections to the regulator, the output is fully isolated from the heatsink & rear panel.
This is detailing my portable multi-purpose power pack of my own design. Here is an overview, mainly showing the 4Ah 12v Ni-Cd battery pack.
Panel Features – Bottom: Car cigar lighter socket, main power keyswitch. Top: LED toggle switch, provision for upcoming laser project, Red main Power LED, 7A circuit breaker.
Top: Toggle switch serving post terminals, USB Port.
Post terminals supply unregulated 12v for external gadgets. USB port is standard 5v regulated for charging phones, PDAs etc.
Bottom: Pair of XLR connectors for external LED lights. Switches on their right control power & the knob controls brightness.
Additions are being made to this all the time, the latest being a 2W laser diode driver. Update to come soon!
This is a small audio mixer, marketed for camcorder audio dubbing.
I/O Panel on the rear of the unit. Contains a small preamp, but will not drive speakers directly. Power is a 9v battery or plugpack.
Front of the PCB removed from the case. Mic preamp bottom right corner. Each channel has it’s own Preamp IC between the faders.
Rear of the PCB.
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