I thought this would be of interest, as it’s from a drive circa 2001, (DVD-CD-RW).
It’s the biggest & most complex optical block I’ve ever seen, with totally separate beam paths for the IR CD beam & the visible DVD beam. It also combines the use of bare laser diodes & combined diode/photodiode array modules for the pickup.
Cover Removed
Here’s a look at the optics inside the sled, on the left is a bare laser diode & photodiode array, for the CD reading, and the bottom right has the DVD combined LD/PD array module. The beam from the CD diode has to pass though some very complex beam forming optics & a prism to fold it round to the final turning mirror to the objective lens at top center.
There are also two separate photodiodes which are picking up the waste beam from the prisms, most likely for power control.
This is just a few notes on the repair of an eCig battery (1Ah Tornado).
These batteries seem to have a flaw in which they will randomly stop working, while still displaying all the normal activity of the battery.
Here is what I have found.
Control PCB
Here the battery has been partially disassembled, with the control circuitry exposed here at the end of the unit. All the wiring here is fine & the electronics themselves are also OK, due to the LEDs still operating as normal when the button is pushed. The 1000mAh Li-Poly cell is to the right.
Ground Wire
Here the end cap has been removed from the opposite end of the battery & the problem is found: the short wire here is the GND return for the atomiser, normally connected to the negative terminal of the battery in the tube, however here it has broken off.
This is most likely due to either the cell moving inside the tube during normal operation, weakening the solder joint, or simply a bad solder job from the factory. (This lead-free ROHS bullshit is to blame).
Repaired
Here the wire has been successfully soldered back on to the battery tab. I have also added a small dab of hot glue to hold the battery in place on the inside of the tube, & replaced the solder on the joints with real 60/40 leaded solder. £15 saved.
This unit was bought from eBay to experiment with Magnetic Stripe cards, for little money. This unit is capable of reading & writing all 3 tracks, & both Hi-Co & Lo-Co card types.
Interfaced to a PC through USB, this has a built in PL2303 USB-Serial IC & requires 3A at 9v DC to operate.
The 3 Indicator LEDs on the top of the unit can be toggled by the included software for Power/OK/Fault condition signalling.
Unit Bottom
Bottom of the unit with the model labels.
Model Label
Closeup of the model label & serial number.
PCB Bottom
Here the bottom cover has been removed, showing the main PCB. The pair of large ICs bottom center interface with the magnetic heads. The IC above them has had the markings sanded off.
USB-Serial Interface
Closeup of the Prolific PL-2303 USB-Serial converter IC.
PCB Top
Here the connections to the R/W heads are visible, current limiting resistors at the left for the write head, a pair of signal relays, a pair of optoisolators & a LM7805 linear voltage regulator.
LEDs
Here is the trio of indicator LEDs on a small sub-board.
Frame Bottom
The PCB has been removed from the main frame here, the only component visible is the rotary encoder.
Rotary Encoder
The rotary encoder has a rubber wheel fitted, which reads the speed of the card as it is being swiped for writing. This allows the control logic to write the data to the stripe at the correct rate for the speed of the card. This allows the unit to write cards from 5-50 inches per second speed.
The Write head is directly behind the rubber pressure roller.
Read/Write Heads
Here you can see the R/W head assembly. The write head is on the right, read on the left. When a card is written to, it immediately gets read by the second head for verification.
A 5 megapixel digital camera from Vivitar. Visible here is the lens, viewfinder & flash.
Back
Rear of the unit showing the LCD & user control buttons.
Cover Removed
Front frame removed showing some of the internals. Shutter assembly & lens in centre, battery compartment at left.
Rear Cover Removed
Rear frame removede, showing the LCD module & tactile switches.
LCD
LCD module removed from the PCB
Flash PCB
Flash PCB removed. Transformer is fed with the 4.5v from the 3 AA cells & steps it up to ~300v DC for the flash capacitor. A pulse transformer energizes an electrode next to the Xenon flash tube with ~5kV to ionize the gas.
Main PCB
Main PCB removed. Internal flash ROM & RAM IC visible above the SD card socket. USB connector is at the top right, next to the piezo buzzer.
CPU
Main processor on reverse side of the PCB.
Image Sensor
Closeup of the CMOS image sensor with the lens assembly removed.
An early speed radar detector from the early 90’s. Pictures showing the front of the unit with the option buttons.
Bottom
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 Top
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.
Waveguide Horn
Shot down the waveguide, showing the detector diodes at the end.
LEDs
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.
PCB Bottom
Bottom of the PCB, showing detection logic. Piezo buzzer top left.
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.
Front Panel Right
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.
Front Panel Left
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!
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
For all those interested, here’s the bottom label.
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.
Here is a Bosch 14.4v Professional cordless drill/driver, recovered from a skip!
It was thrown away due to a gearbox fault, which was easy to rectify.
Internals
Here is the drill with the side cover removed, showing it’s internal parts. The speed controller is below the motor & gearbox here. The unit at the top consists of a 12v DC motor, coupled to a 4-stage epicyclic gearbox unit, from which can be selected 2 different ratios, by way of the lever in the centre of the box. This disables one of the gear stages. There is a torque control clutch at the chuck end of the gearbox, this was faulty when found.
Motor
Here is the drive motor disconnected from the gearbox, having a bayonet fitting on the drive end.
Drive Gear
This is the primary drive gear of the motor, which connects with the gearbox.
Cooling Fan
The motor is cooled by this fan inside next to the commutator, drawing air over the windings.
Gearbox
This is the gearbox partially disassembled, showing the 1st & second stages of the geartrain. The second stage provides the 2 different drive ratios by having the annulus slide over the entire gearset, disabling it entirely, in high gear. The annulus gears are a potential weak point in this gearbox, as they are made from plastic, with all other gears being made of steel.
Charger
Here is the charging unit for the Ni-Cd battery packs supplied with the drill. The only indicator is the LED shown here on the front of the unit, which flashes while charging, & comes on solid when charging is complete. Charge termination is by way of temperature monitoring.
Transformer
Here the bottom of the charger has been removed, showing the internal parts. An 18v transformer supplies power to the charger PCB on the left.
Charger PCB
This is the charger PCB, with a ST Microelectronics controller IC marked 6HKB07501758. I cannot find any information about this chip.
Battery Pack Internals
Here is a battery pack with the top removed, showing the cells.
Temperature Sensor
This is the temperature sensor embedded inside the battery pack that is used by the charger to determine when charging is complete.
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