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Sterling ProCharge Ultra PCU1210 Teardown & Repair

The Sterling charger we’ve had on board nb Tanya Louise since Feb 2014 has bitten the dust, with 31220 hours on it’s internal clock. Since we’re a liveaboard boat, this charger has had a lot of use while we’re on the mooring during winter, when the solar bank isn’t outputting it’s full rate. First, a bit of a teardown to explore the unit, then onto the repair:


Active PFC Section
Active PFC Section

There’s the usual mains input filtering on the left, with the bridge rectifier on it’s heatsink.
Underneath the centre massive heatsinks is the main transformer (not visible here) & active PFC circuit. The device peeking out from underneath is the huge inductor needed for PFC. It’s associated switching MOSFET is to the right.

Logic PSU Section
Logic PSU Section

On the other side of the PFC section is the main DC rail filter electrolytic, a 450v 150µF part. Here some evidence of long-term heating can be seen in the adhesive around the base, it’s nearly completely turned black! It’s not a decent brand either, a Chinese CapXon.
The PCB fuse just behind it is in the DC feed to the main switching supply, so the input fuse only protects the filter & Active PFC circuitry. Luckily this fuse didn’t blow during the failure, telling me the fault was earlier in the power chain.
The logic circuits are powered by an independent switching supply in the centre, providing a +5v rail to the microcontroller. The fan header & control components are not populated in this 10A model, but I may end up retrofitting a fan anyway as this unit has always run a little too warm. The entire board is heavily conformal coated on both sides, to help with water resistance associated with being in a marine environment. This has worked well, as there isn’t a single trace of moisture anywhere, only dust from years of use.
There is some thermal protection for the main SMPS switching MOSFETS with the Klixon thermal fuse clipped to the heatsink.

DC Output Section
DC Output Section

The DC output rectifiers are on the large heatsink in the centre, with a small bodge board fitted. Due to the heavy conformal coating on the board I can’t get the ID from this small 8-pin IC, but from the fact that the output rectifiers are in fact IRF1010E MOSFETS, rated at 84A a piece, this is an synchronous rectifier controller.
Oddly, the output filter electrolytics are a mix of Nichicon (nice), and CapXon (shite). A bit of penny pinching here, which if a little naff since these chargers are anything but cheap. (£244.80 at the time of writing).
Hiding just behind the electrolytics is a large choke, and a reverse-polarity protection diode, which is wired crowbar-style. Reversing the polarity here will blow the 15A DC bus fuse instantly, and may destroy this diode if it doesn’t blow quick enough.

DC Outputs
DC Outputs

Right on the output end are a pair of large Ixys DSSK38 TO220 Dual 20A dual Schottky diodes, isolating the two outputs from each other, a nice margin on these for a 10A charger, since the diodes are paralleled each channel is capable of 40A. This prevents one bank discharging into another & allows the charger logic to monitor the voltages individually. The only issue here is the 400mV drop of these diodes introduce a little bit of inefficiency. To increase current capacity of the PCB, the aluminium heatsink is being used as the main positive busbar. From the sizing of the power components here, I would think that the same PCB & component load is used for all the chargers up to 40A, since both the PFC inductor & main power transformer are massive for a 10A output. There are unpopulated output components on this low-end model, to reduce the cost since they aren’t needed.

Front Panel Control Connections
Front Panel Control Connections

A trio of headers connect all the control & sense signals to the front panel PCB, which contains all the control logic. This unit is sensing all output voltages, output current & PSU rail voltages.

Front Panel LEDs
Front Panel LEDs

The front panel is stuffed with LEDs & 7-segment displays to show the current mode, charging voltage & current. There’s 2 tactile switches for adjustments.

Front Panel Reverse
Front Panel Reverse

The reverse of the board has the main microcontroller – again identifying this is impossible due to the heavy conformal coat. The LEDs are being driven through a 74HC245D CMOS Octal Bus Transceiver.


Now on to the repair! I’m not particularly impressed with only getting 4 years from this unit, they are very expensive as already mentioned, so I would expect a longer lifespan. The input fuse had blown in this case, leaving me with a totally dead charger. A quick multimeter test on the input stage of the unit showed a dead short – the main AC input bridge rectifier has gone short circuit.

Bridge Rectifier Removed
Bridge Rectifier Removed

Here the defective bridge has been desoldered from the board. It’s a KBU1008 10A 800v part. Once this was removed I confirmed there was no longer an input short, on either the AC side or the DC output side to the PFC circuit.

Testing The Rectifier
Testing The Rectifier

Time to stick the desoldered bridge on the milliohm meter & see how badly it has failed.

Yep, Definitely Shorted
Yep, Definitely Shorted

I’d say 31mΩ would qualify as a short. It’s no wonder the 4A input fuse blew instantly. There is no sign of excessive heat around the rectifier, so I’m not sure why this would have failed, it’s certainly over-rated for the 10A charger.

Testing Without Rectifier
Testing Without Rectifier

Now the defective diode bridge has been removed from the circuit, it’s time to apply some controlled power to see if anything else has failed. For this I used a module from one of my previous teardowns – the inverter from a portable TV.

Test Inverter
Test Inverter

This neat little unit outputs 330v DC at a few dozen watts, plenty enough to power up the charger with a small load for testing purposes. The charger does pull the voltage of this converter down significantly, to about 100v, but it still provides just enough to get things going.

It's Alive!
It’s Alive!

After applying some direct DC power to the input, it’s ALIVE! Certainly makes a change from the usual SMPS failures I come across, where a single component causes a chain reaction that writes off everything.

Replacement Rectifier
Replacement Rectifier

Unfortunately I couldn’t find the exact same rectifier to replace the shorted one, so I had to go for the KBU1010, which is rated for 1000v instead of 800v, but the Vf rating (Forward Voltage), is the same, so it won’t dissipate any more power.

Soldered In
Soldered In

Here’s the new rectifier soldered into place on the PCB & bolted to it’s heatsink, with some decent thermal compound in between.

Input Board
Input Board

Here is the factory fuse, a soldered in device. I’ll be replacing this with standard clips for 20x5mm fuses to make replacement in the future easier, the required hole pattern in the PCB is already present. Most of the mains input filtering is also on this little daughterboard.

Fuse Replaced
Fuse Replaced

Now the fuse has been replaced with a standard one, which is much more easily replaceable. This fuse shouldn’t blow however, unless another fault develops.

Full Load Test
Full Load Test

Now everything is back together, a full load test charging a 200Ah 12v battery for a few hours will tell me if the fix is good. This charger won’t be going back into service onboard the boat, it’s being replaced anyway with a new 50A charger, to better suit the larger loads we have now. It won’t be a Sterling though, as they are far too expensive. I’ll report back if anything fails!

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PowerAdd Pilot X7 20,000mAh Powerbank & Fast Charging Mod

PowerAdd Pilot X7
PowerAdd Pilot X7

Here’s the biggest portable USB powerbank I’ve seen yet – the PowerAdd Pilot X7, this comes with a 20Ah (20,000mAh) capacity. This pack is pretty heavy, but this isn’t surprising considering the capacity.

USB Ports & LED
USB Ports & LED

The front of the pack houses the usual USB ports, in this case rated at 3.4A total between the ports. There’s a white LED in the centre as a small torch, activated by double-clicking the button. A single click of the button lights up the 4 blue LEDs under the housing that indicate remaining battery capacity. Factory charging is via a standard µUSB connector in the side, at a maximum of 2A.

PCB Front
PCB Front

The front of the PCB holds the USB ports, along with most of the main control circuitry. At top left is a string of FS8025A dual-MOSFETs all in parallel for a current carrying capacity of 15A total, to the right of these is the ubiquitous DW01 Lithium-Ion protection IC. These 4 components make up the battery protection – stopping both an overcharge & overdischarge. The larger IC below is an EG1501 multi-purpose power controller.

This chip is doing all of the heavy lifting in this power pack, dealing with all the DC-DC conversion for the USB ports, charge control of the battery pack, controlling the battery level indicator LEDs & controlling the torch LED in the centre.

EG1501 Example
EG1501 Example

The datasheet is in Chinese, but it does have an example application circuit, which is very similar to the circuitry used in this powerbank. A toroidal inductor is nestled next to the right-hand USB port for the DC-DC converter, and the remaining IC next to it is a CW3004 Dual-Channel USB Charging Controller, which automatically sets the data pins on the USB ports to the correct levels to ensure high-current charging of the devices plugged in. This IC replaces the resistors R3-R6 in the schematic above.
The DC-DC converter section of the power chain is designed with high efficiency in mind, not using any diodes, but synchronous rectification instead.

PCB Back
PCB Back

The back of the PCB just has a few discrete transistors, the user interface button, and a small SO8 IC with no markings at all. I’m going to assume this is a generic microcontroller, (U2 in the schematic) & is just there to interface the user button to the power controller via I²C.

Cells
Cells

Not many markings on the cells indicating their capacity, but a full discharge test at 4A gave me a resulting capacity of 21Ah – slightly above the nameplate rating. There are two cells in here in parallel, ~10Ah capacity each.

XT60 Battery Connector
XT60 Battery Connector

The only issue with powerbanks this large is the amount of time they require to recharge themselves – at this unit’s maximum of 2A through the µUSB port, it’s about 22 hours! Here I’ve fitted an XT60 connector, to interface to my Turnigy Accucell 6 charger, increasing the charging current capacity to 6A, and reducing the full-charge time to 7 hours. This splits to 3A charge per cell, and after some testing the cells don’t seem to mind this higher charging current.

Battery Connector Wiring
Battery Connector Wiring

The new charging connector is directly connected to the battery at the control PCB, there’s just enough room to get a pair of wires down the casing over the cells.

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eBay Special – LED Disco Light With Built In MP3 Player

Here’s an eBay oddity – it’s got the same light & lens mechanism as the cheap “disco light” style bulbs on eBay, but this one is battery powered & has a built in MP3 player.

MP3 Disco Light
MP3 Disco Light

This device simply oozes cheapness. The large 4″ plastic dome lens sits on the top above the cheap plastic moulding as a base, which also contains the MP3 player speaker.

Controls
Controls

There are few controls on this player, the volume buttons are combined with the skip track buttons, a long press operates the volume control, while a short press skips the tracks. Several options for getting this thing to play music are provided:

  • Bluetooth – Allows connection from any device for bluetooth audio
  • USB – Plugging in a USB flash drive with MP3 files
  • SD Card – Very similar to the USB flash drive option, just a FAT32 formatted card with MP3 files
  • Aux – There’s no 3.5mm jack on this unit for an audio input, instead a “special” USB cable is supplied that is both used to charge the built in battery & feed an audio signal. This is possible since the data lines on the port aren’t used. But it’s certainly out of the ordinary.
Top Removed
Top Removed

The top comes off with the removal of a single screw in the centre of the lens. The shaft in the centre that holds the lens is attached to a small gear motor under the LED PCB. There’s 6 LEDs on the board, to form an RGB array. Surprisingly for a very small battery powered unit these are bright to the point of being utterly offensive.

Mainboard
Mainboard

Here’s the mainboard removed from the plastic base. There’s not much to this device, even with all the options it has. The power switch is on the left, followed by the Mini-B USB charging port & aux audio input. The USB A port for a flash drive is next, finishing with the µSD slot. I’m not sure what the red wire is for on the left, it connects to one of the pins on the USB port & then goes nowhere.

Audio Amplifier
Audio Amplifier

The audio amplifier is a YX8002D, I couldn’t find a datasheet for this, but it’s probably Class D.

Main Chipset
Main Chipset

Finally there’s the main IC, which is an AC1542D88038. I’ve not been able to find any data on this part either, it’s either a dedicated MP3 player with Bluetooth radio built in, or an MCU of some kind.The RF antenna for the Bluetooth mode is at the top of the board.
Just behind the power switch is a SOT23-6 component, which should be the charger for the built in Lithium Ion cell.

Lithium Ion Cell
Lithium Ion Cell

The cell itself is a prismatic type rated in the instructions at 600mAh, however my 1C discharge test gave a reading of 820mAh, which is unusual for anything Li-Ion based that comes from eBay 😉
There is cell protection provided, it’s under the black tape on the end, nothing special here.

The main issue so far with this little player is the utterly abysmal battery life – at full volume playing MP3s from a SD card, the unit’s current draw is 600mA, with the seizure & blindness-inducing LEDs added on top, the draw goes up to about 1200mA. The built in charger is also not able to keep up with running the player while charging. This in all only gives a battery life of about 20 minutes, which really limits the usability of the player.

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ELuc BLU4 Intelligent Lithium Battery Charger W/Bluetooth

BLU4 Battery Charger
BLU4 Battery Charger

Here’s another battery charger designed for lithium chemistry cells, the BLU4. This charger doesn’t display much on it’s built in LCD, apart from basic cell voltage & charging current limits, as it has a built in Bluetooth module that will link into an Android or iOS app.

Above the charger is operating with 4 brand new cells, at a current of 500mA per cell. If only a pair of cells is being charged, the current can be increased to 1A per cell.

LCD
LCD

Not much in the way of user interface on the charger, a tiny LCD & single button for cycling through the display options.

Dataplate
Dataplate

The usual stuff on the data plate, the charger accepts an input of 12v DC at 1A.

Bottom Cover Removed
Bottom Cover Removed

Removing the 6 screws on the bottom of the casing allows the board to be seen. Not much on the bottom, the 4 cell negative connections can be seen, with their springs for adjusting for cell length.

MOSFETs
MOSFETs

There’s a couple of P-Channel FETs on the bottom side for the charging circuits, along with some diodes.

Main PCB
Main PCB

The main PCB is easily removed after the springs are unhooked from the terminals. Most of the power circuitry is located on the top side near the power input. There are 4 DC-DC converters on board for stepping the input 12v down to the 4.2v required to charge a lithium cell.

Second Controller
Second Controller

Not entirely sure what this IC is in the bottom corner, as it’s completely unmarked. I’m guessing it’s a microcontroller though.

DC Input Side
DC Input Side

The top left of the board is crammed with the DC-DC converters, all the FETs are in SO8 packages.

DC-DC Converters
DC-DC Converters

One pair of DC-DC inductors is larger than the other pair, for reasons I’m unsure of.

Bluetooth Module
Bluetooth Module

Bluetooth connectivity is provided by this module, which is based around a TTC2541 BLE IC.

Microcontroller
Microcontroller

Below the Bluetooth module is yet another completely unmarked IC, the direct link to the BLE interface probably means it’s another microcontroller. The Socket to the left of the IC is the connector for the front panel LCD & button.

LCD PCB
LCD PCB

There’s not much to the LCD itself, so I won’t remove this board. The LCD controller is a COB type device, from the number of connections it most likely communicates with the micro via serial.

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Sony Xperia Z3 50% Battery Problems

Recently my phone decided it was going to die a battery-related death, and having not found much useful information on the Great Google, (all the information I could find, was hinting at many issues from firmware to a faulty motherboard, nobody seems to have actually done any investigation into similar issues), I decided to dig into the phone to try & repair the problem.

Broken Flex
Broken Flex

The phone would work correctly for a while, then with the slightest movement or knock, would spontaneously switch off, and not turn back on without being whacked on a hard surface.
This symptom pointed me at a power connection problem. After removing the back of the phone (glass & heavily glued in place, so an awkward process), This was what I was presented with on the cell flex PCB.
In the above photo, the positive connection to the flex is fractured just after the solder joint with the BMS board.

Flex Repair
Flex Repair

I managed to scrape some of the insulation off the flex PCB & solder a jumper on to restore power. Unfortunately, this repair generated another fault, where the battery level was always shown at 50%, and plugging into a USB supply wouldn’t charge the phone. The other two pins on the cell are for communication & temperature sensing, clearly one of these traces was also broken in the flex.
The above photo has a pair of very small wire tails as well, for connecting an external charger.

50% Battery
50% Battery

Here’s a screenshot of the phone with the original cell, even though it’s at about 4.15v (virtually fully charged). The battery management is having trouble talking to the phone, so for safety reasons, the charging logic refuses point-blank to charge the thing up.

Flex Cable
Flex Cable

The connector on the cell & phone motherboard is absolutely tiny, so I didn’t fancy attempting to solder on any bridge wires to try & bypass the broken flex.

Battery BMS
Battery BMS

The cell BMS has some intelligence on board, besides the usual over-current, over-charge & under-charge protection. The very small IC on the right has a Microchip logo, and the marking FT442, but I was unable to dig up any datasheets. The current sense resistor is directly connected to this IC, along with the main power FET to the left.

BMS Reverse
BMS Reverse

On the other side of the BMS board is another IC, again unidentifiable, and what looks like a bare-die, or CSP IC.

20160625_233656

At this stage I figured the only way forward was to buy a new battery, eBay turned one up for less than £5. Above is the new battery fitted to the phone, datestamped 2014, so definitely old stock.

100% Battery
100% Battery

Booting the phone with the new battery quickly lets me know the fix worked, with a 100% reading & the ability to again charge properly!

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Multifunction LCD Power Meter MHF-8020P

LCD Unit
LCD Unit

I recently came across these on eBay, so I thought I’d grab one to see how they function, with all the metrics they display, there’s potential here for them to be very useful indeed.
One of the best parts is that no wiring is required between the sensor board & the LCD head unit – everything is transmitted over a 2.4GHz data link using NRF24L01 modules.
Above is the display unit, with it’s colour LCD display. Many features are available on this, & they appear to be designed for battery powered systems.

Monitor PCB
Monitor PCB

Another PCB handles the current & voltage sensing, so this one can be mounted as close to the high current wiring as possible.

Monitor PCB Microcontroller
Monitor PCB Microcontroller

The transmitter PCB is controlled with an STM8S003F3 microcontroller from ST Microelectronics. This is a Flash based STM with 8KB of ROM, 1KB of RAM & 10-bit ADC. The NRF24L01 transceiver module is just to the left.
There’s only a single button on this board, for pairing both ends of the link.

Output MOSFET
Output MOSFET

The high current end of the board has the 0.0025Ω current shunt & the output switch MOSFET, a STP75NF75 75v 75A FET, also from ST Microelectronics. A separate power source can be provided for the logic via the blue terminal block instead of powering from the source being measured.

LCD Unit Rear
LCD Unit Rear

Here’s the display unit, only a pair of power terminals are provided, 5-24v wide-range input is catered for.

LCD Unit PCB
LCD Unit PCB

Unclipping the back of the board reveals the PCB, with another 2.4GHz NRF24L01 module, and a STM8S005K6 microcontroller in this case. The switching power supply that handles the wide input voltage is along the top edge of the board.

Unfortunately I didn’t get any instruction manual with this, so some guesswork & translation of the finest Chinglish was required to get my head round the way everything works. To make life a little easier for others that might have this issue, here’s a list of functions & how to make them work.

LCD Closeup
LCD Closeup

On the right edge of the board is the function list, a quick press of the OK button turns a function ON/OFF, while holding it allows the threshold to be set.
When the output is disabled by one of the protection functions, turning that function OFF will immediately enable the output again.
The UP/DOWN buttons obviously function to select the desired function with the cursor just to the left of the labels. Less obviously though, pressing the UP button while the very top function is selected will change the Amp-Hours display to a battery capacity icon, while pressing DOWN while the very bottom function is selected will change the Watts display to Hours.
The round circle to the right displays the status of a function. Green for OK/ON Grey for FAULT/OFF.

  • OVP: Over voltage protection. This will turn off the load when the measured voltage exceeds the set threshold.
  • OPP: Over power protection. This function prevents a load from pulling more than a specified number of watts from the supply.
  • OCP: Over current protection. This one’s a little more obvious, it’ll disable the output when the current measured exceeds the specified limit.
  • OUT: This one is the status of the output MOSFET. Can also be used to manually enable/disable the output.
  • OFT: Over time protection. This one could be useful when charging batteries, if the output is enabled for longer than the specified time, the output will toggle off.
  • OAH: Over Amp-Hours protection. If the counted Amp-Hours exceeds the set limit, the output will be disabled.
  • Nom: This one indicates the status of the RF data link between the modules, and can be used to set the channel they operate on.
    Pairing is achieved by holding the OK button, selecting the channel on the LCD unit, and then pressing the button on the transmitter board. After a few seconds, (it appears to scan through all addresses until it gets a response) the display will resume updating.
    This function would be required if there are more than a single meter within RF range of each other.

I’ve not yet had a proper play with all the protection functions, but a quick mess with the OVP setting proved it was very over-sensitive. Setting the protection voltage to 15v triggered the protection with the measured voltage between 12.5v-13.8v. More experimentation is required here I think, but as I plan to just use these for power monitoring, I’ll most likely leave all the advanced functions disabled.

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Turnigy Accucell 6 Multi-Chemistry Charger

Accucell 6
Accucell 6

A lot of the electronics I use & projects I construct use batteries, mainly of the lithium variety. As charging this chemistry can be a little explosive if not done correctly, I decided a proper charger was required. This charger is capable of handling packs up to 6 cells for Lithium, and up to 20v for lead-acids.

External Connections
External Connections

The usual DC input barrel jack on the left, with an external temp sensor for fast charging NiCd/NiMH chemistry batteries. The µUSB port registers under Linux as USB HID, probably so drivers aren’t required. Unfortunately the software is Windows only, but it doesn’t provide anything handy like charging graphs or stats. Just a way to alter settings & control charging from a PC. On other versions of this charger there’s a setting to change the temp sensor port into a TTL serial output, which would be much handier.

Output & Balance
Output & Balance

The other side of the charger has the main DC output jacks & the pack balancing connections.

Cover Removed
Cover Removed

Here’s the top cover removed from the charger, showing most of the internals. A standard HD44780 LCD provides the user interface, the CPU & it’s associated logic is hidden under there somewhere.
The PCB has nice heavy tracks to handle the 6A of current this charger is capable of.

Balancing Network
Balancing Network

The output side of the board. Here the resistive pack balancing network can be seen behind the vertical daughter board holding the connectors, along with the output current shunt between the DC output banana jacks & the last tactile button.

Main Logic
Main Logic

Unfortunately the LCD is soldered directly to the board, and my desoldering tool couldn’t quite get all the solder out, so time to get a bit violent. I’ve gently bent the header so I could see the brains of the charger. The main CPU is a Megwin MA84G564AD48, which is an Intel 8081 clone with USB support. Unfortunately I was unable to find a datasheet for this part, and the page on Megwin’s site is Chinese only.

I was hoping it was an ATMega328, as I have seen in other versions of this charger, as there are custom firmwares available to increase the feature set of the charger, but no dice on this one. I do think the µUSB port is unique to this version though, so avoiding models with that port probably would get a hackable version.
There’s some glue logic for controlling the resistor taps on the balancing network, and a few op-amps for voltage & current readings.

Power Switching Devices
Power Switching Devices

All the power diodes & switching FETs for the DC-DC converter are mounted on the bottom of the PCB, and clamped against the aluminium casing when the PCB is screwed down. Not the best way to ensure great contact, but Chinese tech, so m’eh.

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Totally Wicked Forza / JoyeTech eVIC 60W Teardown

Display
Display

I’ve been a vaper now for many years, after giving up the evil weed that is tobacco. Here’s my latest acquisition in the vaping world, the JoyeTech eVIC 60W. This one is branded by Totally Wicked as the Forza VT60.

18650 Cell
18650 Cell

Powered by a single 18650 Li-Ion cell, this one is a Sony VTC4 series, 2100mAh.

Under the battery a pair of screws hold the electronics in the main cast alloy casing.

OLED Display
OLED Display

After removing the screws, the entire internal assembly comes out of the case, here’s the top of the PCB with the large OLED display in the centre.

USB Jack
USB Jack

On the right side of the board is the USB jack for charging & firmware updates. The adjustment buttons are also at this end.

Output
Output

On the left side of the board is the main output connector & the fire button. Unlike many eCigs I’ve torn down before, the wiring in this one is very beefy – it has to be to handle the high currents used with some atomizers – up to 10A.

PCB Reverse
PCB Reverse

Removing the board from the battery holder shows the main power circuitry & MCU. The aluminium heatsink is thermally bonded to the switching MOSFETs, a pair under each end. The switching inductor is under the gap in the centre of the heatsink.

DC-DC Converter
DC-DC Converter

A close up of the heatsink shows the very slim inductor under the heatsink.

Microcontroller
Microcontroller

The main MCU in this unit has a very strange part number, which I’ve been unable to find information on, but it’s probably 8081 based.

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Maplin 3W LED Torch Charger Fail

A member of the family recently bought one of these torches from Maplin electronics, and the included chargers for the 18650 lithium-ion cells leave a lot to be desired.

Torch
Torch

Here’s what’s supplied. The torch itself is OK – very bright, and a good size. Me being cynical of overpriced Chinese equipment with lithium batteries, I decided to look in the charging base & the cigar-lighter adaptor to see if there was any actual charging logic.

Charger
Charger

Answer – nope. Not a single active component in here. It’s just a jack connected to the battery terminals. There’s all the space there to fit a proper charging circuit, but it’s been left out to save money.

OK then, is it inside the cigarette lighter adaptor?

Lighter Adaptor
Lighter Adaptor

Nope. Not a single sign of anything resembling a Lithium-Ion charger IC. There’s a standard MC34063A 1.5A Buck converter IC on the bottom of the PCB, this is what’s giving the low voltage output for the torch.

Charger Bottom
Charger Bottom

Here’s the IC – just a buck converter. The output voltage here is 4.3v. This is higher than the safe charging voltage of a lithium ion cell, of 4.2v.

The cells supplied are “protected” versions, having charge/discharge protection circuitry built onto the end of the cell on a small PCB, this makes the cell slightly longer than a bare 18650, so it’s easy to tell them apart.
The manufacturers in this case are relying on that protection circuit on the cell to prevent an overcharge condition – this isn’t the purpose they’re designed for, and charging this way is very stressful for the cells. I wouldn’t like to leave one of these units charging unattended, as a battery explosion might result.

More to come shortly when I build a proper charger for this torch, so it can be recharged without fearing an alkali metal fire!

73s for now folks!

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Opticon OPN-2001 Barcode Scanner

OPN-2001
OPN-2001

Random teardown time!

The OPN-2001 is a very small handheld barcode data collection device, used for stock keeping, inventory, etc.

It’s powered by an internal Li-Poly cell, at 150mAh, and has storage for 1000 barcodes in it’s internal memory.

USB
USB

The unit is charged via it’s USB port, the data can also be downloaded using this interface.

ID Label
ID Label

Here’s the bottom of the unit with it’s label. Serial number removed to protect the guilty. 😉

Cover Removed
Cover Removed

Here the bottom cover has been removed from the scanner, showing the internals. The barcode engine is on the left, this contains all the hardware & logic for scanning & storing the barcode data. The Li-Poly cell is under the FFC cable wrapped in foam tape for protection.

PCB Removed
PCB Removed

Here’s the PCB & engine assembly removed from the casing. The lower PCB appears to just handle the user interface buttons, beeper & USB power & charging circuitry. All the processing logic is on the barcode engine itself.

PCB Reverse
PCB Reverse

Here’s the back of the support PCB, with the pair of buttons for scanning & deleting barcodes. Also on this board is a 32kHz clock crystal & a Ricoh RV5C386A RTC IC. This communicates with the main processor via I²C for storing the date & time with the barcodes. At the bottom right corner are some of the power supply passives.

Support PCB
Support PCB

Here’s the other side of the support PCB, with the beeper, battery connector & the switching regulator to provide the barcode engine with 3.3v power.

Barcode Engine
Barcode Engine

Here’s the barcode engine itself, which is absolutely tiny, at roughly 20mm square. The main processor & it’s associated Flash ROM are on this PCB. The main processor has an ARM7 32bit core, with 64kB of RAM, and onboard 512kB of ROM for program & barcode storage.

Mirror
Mirror

Here’s the business end of the barcode engine, the mirror vibrates at 100Hz to produce the scan line. The laser diode is rated at 1mW, 650nm. This is in the deep red range.

 

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Baofeng Battery Capacity Lies

I’ve had a couple of larger batteries for my UV-5Rs for some time now, and decided to do a quick teardown to see if they’re actually the capacity claimed.

BL-5L Battery
BL-5L Battery

Here’s the label, claiming 3800mAh (3.8Ah) of battery capacity.
These batteries are held together with glue, but a good way to get these kinds of things open is by whacking the seams with the handle of a screwdriver. This cracks the glue without damaging the casing.

Battery Cracked Open
Battery Cracked Open

After a few minutes of cracking the seams, the battery comes right open. The pair of wires link the protection board on the cells to the DC terminals on the top of the pack. The charging terminals are under the cardboard insulator on the right.

Cells
Cells

Here’s the other half of the case, with the cells themselves. These are wired in series for a 7.2v pack, and at a capacity of 2600mAh (2.6Ah) printed on them, the label clearly lies about the capacity.

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Samsung ETA-U90UWE Adaptor Failure

Here’s an odd & sudden failure, the power adaptor for a Samsung device. It’s been working for months & on being plugged into the mains today the magic blue smoke escaped.

Samsung Charger
Samsung Charger

It’s one of their 2A models, for charging bigger devices like tablets.

Flash Burn
Flash Burn

Strangely for one of these chargers, no glue is used to hold it together – just clips. This made disassembly for inspection much easier. Evidence of a rather violent component failure is visible inside the back casing.

PCB
PCB

Here’s the charger PCB removed from the casing. As to be expected from Samsung, it’s a high quality unit, with all the features of a well designed SMPS.

PCB Reverse
PCB Reverse

However, on turning the board over, the blown component is easily visible. It’s the main SMPS controller IC, with a massive hole blown in the top. The on board fuse has also blown open, but it obviously didn’t operate fast enough to save the circuit from further damage!

 

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Lethal Chinese Mains Adaptors

With every piece of Chinese electronics I obtain, mainly Baofeng radios, they come with a Europlug-type power adaptor, and a universal plug adaptor for the mains.

The charger units aren’t too bad, there’s a fair amount of isolation between the primary & secondary, and even though they’re very simple & cheap, I can’t see any immediate safety problems with them.

The plug adaptors, however, are a different matter. These things are utterly lethal!

Baofeng PSU
Baofeng PSU

Here’s the inside of the PSU. It’s just a very simple SMPS, giving an output of 10v 500mA. The fuse is actually a fusible resistor.

PCB Reverse
PCB Reverse

Here’s the back of the PCB with the SMPS control IC. I can’t find any English datasheets for this part unfortunately.

Universal Travel Adaptor
Universal Travel Adaptor

Here’s the dangerous adaptor. There’s no safety shield, so the live parts are exposed.

Internals
Internals

Here’s the adaptor split apart. The output contacts are on the left, and rely just on pressure to make contact with the brass screws on the mains input pins to provide power.
This is a very poor way to get a connection, a dirty or worn contact here would create a lot of heat if any significant power is pulled through, and could quite possibly result in a fire.

Not surprisingly, I bin these things as soon as I open the box, and charge all my radios with a 12v charging system.

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Baofeng UV-5R RF Power Measurements

I’ve noticed that the RF power output from the Chinese radios can be quite variable from model to model, and even from individual radios of the same model & batch.
I’ve bought an RF Power meter (GY561) to do some tests on the HTs I have at present.

All tests were performed with the radio fully charged & still on the charging base, to make sure the supply voltage remained constant at 8.4v throughout the tests.
Frequencies used were 145.500 & 433.500 for VHF & UHF respectively.
The power meter was connected with ~8″ of RG174 Coax.


 High Power:


UV-5R 1 (S/N: 13U1136132):
VHF: 6.3W
UHF: 4.9W

UV-5R 2 (S/N: 13U1136114):
VHF: 6.5W
UHF: 5.2W

UV-5R 3 (S/N: 130U541416):
VHF: 7.1W
UHF: 6.3W


Low Power:


UV-5R 1 (S/N: 13U1136132):
VHF: 2W
UHF: 1.2W

UV-5R 2 (S/N: 13U1136114):
VHF: 2.3W
UHF: 1.5W

UV-5R 3 (S/N: 130U541416):
VHF: 2.7W
UHF: 2.1W

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Mobile Radio Shack Bag

There are times when I am frequently away from home base, usually either on the canal system or at a festival. During these times it’s very handy to be able to just grab a bag, without having to be concerned about sorting everything out.

This post will only detail the portable shack bag. The power supply kit that goes along with it with be detailed in another post.

The bag I use is an VHS Camcorder bag from the early 80’s. It’s very well built, & copes easily with the weight of all the radio gear.

Total weight for this system is 13.4lbs (6kg).

Mobile Radio Bag
Mobile Radio Bag

Above is the bag packed. Obligatory International Ameteur Radio Symbol patch front & centre. Being an old camera bag, this easily slings over the shoulder, with it’s padded strap.

Current Equipment
Current Equipment

Here is all the current equipment laid out. All the equipment to enable me to set up a station anywhere.
In the following photos I will go into the details.

Main Radio
Main Radio

First off, my main radio. This is the same Wouxun KG-UV950P mobile rig I have posted about previously. I have heatshrunk the power cable to keep it together & attached my standard power connector to the end. More on these later on.

HTs
HTs

In the bag I also carry three Baofeng UV-5R handhelds. Extremely useful for short range site communications, along with their charger bases. The charging base on the right has been slightly modified to support charging of my main LED torch as well, which uses similar Li-Ion based packs as the Baofengs.

Baofeng 12v Charger
Baofeng 12v Charger

As the charger bases for the Baofeng HTs take a supply of 10v DC, I have constructed a 12v adaptor system for them. (Which utter prat of an engineer at Baofeng picked 10v?)

Linear Amplifier & SWR Meter
Linear Amplifier & SWR Meter

Also included is a small Alinco ELH-2320 35W 2m linear amplifier. This was given to me from the local HackSpace in Manchester. (They don’t have any ham members, besides myself). Also here is my small SWR & Power meter, SDR kit & a pair of syringes. These are filled respectively with Copaslip copper loaded grease, (very good for stopping fasteners exposed to the weather from seizing up), and dielectric silicone grease. (I use this stuff for filling connectors that are exposed to the weather – keeps the water out).

Tools
Tools

I always keep essential tools in the bag, here is the small selection of screwdrivers which fit pretty much any screw fastener around, my heavy-duty cable shears (these buggers can cut through starter cable in one go!) and my trusty Gerber Diesel multitool.

Magmount & Pi
Magmount & Pi

Main antenna magmount & a spare Raspberry Pi.

Antenna, Patch Leads, Etc.
Antenna, Patch Leads, Etc.

Finally, the antennas for the HTs, main dual-band antenna (Nagoya SP-45) for the magmount, a small selection of spare plugs, sockets & adaptors. Also here is a roll of self-amalgamating tape, very handy for waterproofing wiring connections (especially when used in conjunction with the silicone grease), & a roll of solder wick.

Now, the main power connectors of choice for my equipment are Neutrik SpeakOn type connectors:

Neutrik SpeakOn
Neutrik SpeakOn

These connectors have many advantages:

  • They are positive locking connectors. No more loose connections.
  • They have a high continuous current rating of 30A RMS.
  • Relatively weather resistant.

Also, they have two pairs of pins – and as some of my bigger non-radio related equipment is 24v, this allows me to use a single set of plugs for everything. Without having to worry about plugging a 12v device into a 24v socket, and letting out the magic blue genie.

Once everything is packed up, here’s the bag:

Packed
Packed

Everything has a neat little pocket for easy access. Some closeups below.

HTs, Magmount
HTs, Magmount
Chargers, Amplifier
Chargers, Amplifier
Main Radio
Main Radio
Small Stuff
Small Stuff

I will post more about my portable power system later on, as this bit of my kit is being revamped at the moment.

Stay tuned!

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Portable Power Pack Battery Replacement

Portable Power Pack
Portable Power Pack

After 13 months of very heavy use at various events, festivals & boat trips, the Li-Po battery pack at the heart of my portable power supply has died.
What initially started as one cell inflating spread to the other cells in the pack over a period of about 3 months, so I have completely replaced the pack with a larger unit.

New Pack
New Pack

The old pack was an 8.8Ah unit at 12.6v. By using smaller burst capacity cells, I have managed to squeeze in a total of 13.2Ah, still leaving space to spare for an extra 3 cell string along the top.

Cell Interconnects
Cell Interconnects

Here is the end of the battery pack, with all the cell interconnects. There are 3 2.2Ah cells in series to give the 12.6v terminal voltage, with 6 of those strings in parallel to give the total Ah rating.

A new charging circuit will be implemented to better handle the volatile chemistry of Li-Po cells, hopefully this will result in the pack lasting longer than a year!

The new higher capacity will hopefully help with power requirements at future events, still being charged during the day by a 24W solar panel, but at night will have to cope with charging two smartphones, two eCigs & running a few watts of LED lighting.
The trial-by-fire will be this year’s Download Festival in June, when I will be operating off-grid for 6 days.

More updates to come on improvements & failures!

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Mobile Power Pack Upgrade

New Regulators
New Regulators

The original LM2577 based regulators I designed into my mobile battery pack turned out to be insufficient for requirements, therefore they have been replaced with higher capacity regulators.

The 12v regulator (left) is a muRata UQQ-12/8-Q12P-C SEPIC converter, providing a max of 8A at 12.1v DC. The 12v rail is also now independently switchable to save power when not in use.

The 5v regulator (right) is a Texas Instruments PTN78020WAZ switching regulator, rated at 6A. The pair of resistors on the back of the regulator set the output voltage to 5.1v.

Also a new addition is a pair of banana sockets & a 2.1mm DC jack, wired into the 12v DC bus, for powering various accessories.

New Additions
New Additions

Below the USB sockets is now a built in eCig charger, to save on USB ports while charging these devices.

IWA National Festival 2013
IWA National Festival 2013

These changes were made after much field testing of the unit at Cassiobury Park, Watford, for the IWA National Waterways Festival.

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Wearable Raspberry Pi – Solar Charging

 

24W Solar Panel
24W Solar Panel

I have acquired a 24W monocrystalline solar panel to charge my portable battery pack while on the move. This panel will be able to charge all devices I carry on a regular basis with nothing but some sunlight!

Info Panel
Info Panel

Info on the panel itself. Rated at 24W with nominal 17.6v DC, 1.36A output.

Regulator
Regulator

I have installed a switching regulator in the back of the panel, where the connections would normally be wired straight to the array of cells. This regulates the voltage down to a constant 13.8v to provide more compatibility with 12v charging equipment. I have tested the output of the panel in late day sun, at 1.27A.

 

 

 

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1.5W 445nm Lab Laser

Assembled
Assembled

Here is a followup from the 1.5W laser module post.

The module has been fitted into a housing, with a 2.2Ah Li-Poly battery pack. Charging is accomplished with an external 12.6v DC power supply.

Above can be seen the pair of switches on the top, the keyswitch must be enabled for the laser to fire.

Armed
Armed

When armed, the ring around the push button illuminates blue, as a warning that the unit is armed.

Switch Wiring
Switch Wiring

Inside the unit. The Li-Poly battery pack is at the bottom, with it’s protection & charging circuitry on the top. The switches are wired in series, with the LED connected to illuminate when the keyswitch is turned to the ON position.

Laser Driver
Laser Driver

The push button applies power to the laser driver module, which regulates the input power to safely drive the semiconductor laser in the aluminium heatsink housing.

 

 

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MicroVision ShowWX+ HDMI Laser Pico Projector

Info
Info

Here’s the teardown of the projector itself! On the right is the info label from the projector, which covers the flex ribbon to the VGA/composite input board below.

This unit is held together with Allen screws, but is easy to get apart.

 

PicoP Display Engine
PicoP Display Engine

Here’s the insides of the projector, with just the top cover removed. The main board can be seen under the shielding can, the Micro HDMI connector is on the left & the MicroUSB connection is on the right. The USB connection is solely for charging the battery & provides no data interface to the unit.

On top of the main board is the shield can covering the PicoP Display Engine driver board, this shield was soldered on so no peek inside unfortunately!

Laser Module
Laser Module

The laser module itself is in the front of the unit, the laser assemblies are closest to the camera, on the left is the Direct Doubled Green module, in the centre is the blue diode, and the red diode on the right. Inside the module itself is an arrangement of mirrors & beamsplitters, used to combine the RGB beams from the lasers into a single beam to create any colour in the spectrum.

Module Innards
Module Innards

 

Here is the module innards revealed, the laser mounts are at the top of the screen, the green module is still mounted on the base casting.
The three dichroic mirrors in the frame do the beam combining, which is then bounced onto the mirror on the far left of the frame, down below the MEMs. From there a final mirror directs the light onto the MEMs scanning mirror before it leaves through the output window.

A trio of photodiodes caters for beam brightness control & colour control, these are located behind the last dichroic turning mirror in the centre of the picture.

Green Module Cavity
Green Module Cavity

This is inside the green laser module, showing the complexity of the device. This laser module is about the size of a UK 5p coin!

Green Module Labeled
Green Module Labeled

 

 

 

 

 

And here on the left is the module components labelled.

 

Main PCB Top
Main PCB Top

Here is the main PCB, with the unit’s main ARM CPU on the right, manufactured by ST.

User buttons are along the sides.

 

Main PCB Bottom
Main PCB Bottom

Other side of the main board, with ICs that handle video input from the HDMI connector, battery charging via the USB port & various other management.

 

 

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BigBen DSi Inductive Charging Dock

Front
Front

Here is a Inductive charger designed for the Nintendo DSi. Cheap Chinese build, but it does work!

Overview
Overview

Top has been removed from the unit here. Most prominent in the centre is a solid steel bar, simply there to give the device some weight.
Pair of Tri-colour LEDs at the front indicates charging status.
Induction coil is on the left, with the controller & oscillator PCB at the top.

PCB Closeup
PCB Closeup

Closeup of the PCB, ICs have had their markings ground off.

Coil
Coil

Induction coil. This couples power into a coil built into a special battery, supplied with the base, to charge it when the DSi is placed on the dock.

Label
Label

Information Label on the base.

Power Input
Power Input

Standard DSi charger port, connects to the charger you get with the DSi. Power switch is on the right.

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Portable Power Pack Charger

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.

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Portable Power Supply

Battery
Battery

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
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
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!

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PSP Slim

Front
Front

Here is a PSP Slim that recently died.

Label
Label

For those that are interested, here is the ID label, this is a PSP-2003.

Front Removed
Front Removed

Here the front of the unit has been removed, showing the first internal components.

Screen Removed
Screen Removed

Here is the unit with the LCD removed, here the mainboard is partially visible.

Left Pad
Left Pad

Left pad unit removed from the PSP, with the left speaker & the memory stick slot cover.

Left Pad Rear
Left Pad Rear

Rear of the left pad assembly, showing the speaker.

Joypad
Joypad

Joypad removed from the casing. Resistive unit.

Output Jack
Output Jack

Headphone/data board removed from the casing. This also has TV-Out on the PSP-200x series.

Mainboard
Mainboard

Mainboard removed. Main CPU is at the top. Sockets around the bottom connect to the UMD drive & UMD Drive.

CPU & GPU
CPU & GPU

Closeup of the main chipset. CPU is the top IC.

Mainboard Rear
Mainboard Rear

Rear of the mainboard, Memory Stick socket on the right.

WiFi Chipset
WiFi Chipset

Closeup of the WiFi chipset & the charging power socket on the right.

Charging Chipset
Charging Chipset

Closeup of the bettery connector & the charge controller IC.

UMD Drive
UMD Drive

UMD Drive removed from the rear of the casing. This is a miniature DVD style drive, using a 635nm visible red laser.

UMD Drive Back
UMD Drive Back

Rear of the UMD drive, showing the laser sled & drive motors. Both the spindle motor & the sled motor are 3-phase brushless type. The laser diode/photodiode array is at the top of the laser sled.

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Bosch GSR 14.4v Pro Drill-Driver

Drill Case
Drill Case

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
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
Motor

Here is the drive motor disconnected from the gearbox, having a bayonet fitting on the drive end.

Drive Gear
Drive Gear

This is the primary drive gear of the motor, which connects with the gearbox.

Cooling Fan
Cooling Fan

The motor is cooled by this fan inside next to the commutator, drawing air over the windings.

Gearbox
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
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
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
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
Battery Pack Internals

Here is a battery pack with the top removed, showing the cells.

Temperature Sensor
Temperature Sensor

This is the temperature sensor embedded inside the battery pack that is used by the charger to determine when charging is complete.