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Arduino Based SWR/PWR Meter – The Board

I recently posted about a small analog SWR/Power meter I got from eBay, and figured it needed some improvement.

After some web searching I located a project by ON7EQ, an Arduino sketch to read SWR & RF power from any SWR bridge.
The Arduino code is on the original author’s page above, his copyright restrictions forbid me to reproduce it here.

I have also noticed a small glitch in the code when it is flashed to a blank arduino: The display will show scrambled characters as if it has crashed. However pushing the buttons a few times & rebooting the Arduino seems to fix this. I think it’s related to the EEPROM being blank on a new Arduino board.

I have run a board up in Eagle for testing, shown below is the layout:

SWR Meter SCH
SWR Meter SCH

The Schematic is the same as is given on ON7EQ’s site.
Update: ON7EQ has kindly let me know I’ve mixed up R6 & R7, so make sure they’re switched round when the board is built ;). Fitting the resistors the wrong way around may damage the µC with overvoltage.

SWR Meter PCB
SWR Meter PCB

Here’s the PCB layout. I’ve kept it as simple as possible with only a single link on the top side of the board.

PCB Top
PCB Top

Here’s the freshly completed PCB ready to rock. Arduino Pro mini sits in the center doing all the work.
The link over to A5 on the arduino can be seen here, this allows the code to detect the supply voltage, useful for battery operation.
On the right hand edge of the PCB are the pair of SMA connectors to interface with the SWR bridge. Some RF filtering is provided on the inputs.

PCB Bottom
PCB Bottom

Trackside view of the PCB. This was etched using my tweaked toner transfer method.

LCD Fitted
LCD Fitted

Here the board has it’s 16×2 LCD module.

Online
Online

Board powered & working. Here it’s set to the 70cm band. The pair of buttons on the bottom edge of the board change bands & operating modes.
As usual, the Eagle layout files are available below, along with the libraries I use.

[download id=”5585″]

[download id=”5573″]

More to come on this when some components arrive to interface this board with the SWR bridge in the eBay meter.

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HPI Savage X 4.6 LiPo Receiver Battery

3S Lithium-Polymer Pack
3S Lithium-Polymer Pack

To provide more run time with the conversion to petrol & spark ignition, I have also upgraded the on-board electronics supply to compensate for the extra ~650mA draw of the ignition module.
This modification is centred around a 3S Lithium-Polymer battery pack, providing a nominal 11.1v to a voltage regulator, which steps down this higher voltage to the ~6v required by the receiver & servo electronics.

Power Regulator
Power Regulator
Power Regulator
Power Regulator

The regulator, shown above, is a Texas Instruments PTN78060WAZ wide-input voltage adjustable regulator. This module has an exceptionally high efficiency of ~96% at it’s full output current of 3A. The output voltage is set by a precision resistor, soldered to the back of the module, in this case 6.5v. Standard RC connectors are used on the regulator to allow connection between the power switch & the radio receiver.

Receiver Box
Receiver Box

Everything tucked away into place inside the receiver box. The 3S 1000mAh LiPo fits perfectly in the space where the original Ni-Mh hump pack was located.
The completely stable output voltage of the regulator over the discharge curve of the new battery gives a much more stable supply to the radio & ignition, so I should experience fewer dropouts. Plus the fact that the engine now relies on power from the receiver pack to run, it’s a built in fail safe – if the power dies to the receiver, the engine also cuts out.

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Potentially Lethal Clone Apple Charger

Charger
Charger

I received this USB supply with a laser module from China that I purchased on eBay. I have heard of these nasty copies of Apple chargers going around, but I’d never received one this bad with a piece of Chinese electronics.

Label
Label

Model No. A1265, so definitely an Apple clone. Apparently capable of +5v DC 1A output. Notice the American NEMA pins. This wouldn’t have been any use to me in the first instance since I am resident in the UK & our mains plugs are significantly different, not to mention significantly safer.

Manufacturer is marked as Flextronics.

Top Of Boards
Top Of Boards

Here is the charger disassembled. Inside the case these two boards are folded together, creating an alarmingly small isolation gap between the mains side of the supply & the 5v output. Both the low voltage output & the feedback loop for the supply runs over the 4-core ribbon cable.
The mains wiring from the board is as thin as hair, insulation included, so there is a big possibility of shorts all over the place from this part of the circuit alone.

Bottom Of Boards
Bottom Of Boards

Bottom of the PCB assemblies. Good luck finding any creepage distance here. There simply isn’t any at all. traces on the +350v DC rail on the mains side of the transformer are no more than 1mm away from the supposedly isolated low voltage side.

Plugging one of these devices into anything is just asking for electrocution.

 

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nb Tanya Louise Hydraulic Generator

Hydraulic Generator Unit
Hydraulic Generator Unit

To accompany the previous two posts about hydraulic generators & their components, here is the actual generator unit itself.

Rated at 8.5kVa 230v AC, this will providea mains supply while the narrowboat is away from her home mooring.

This unit will be attached to the side of the hull in the engine room on rubber vibration isolation mounts, behind the main hydraulic oil tank & is driven from the small gear pump attached to the back of the main propulsion hydraulic pump unit.
Operating pressure is 175 bar, 21L/m flow rate to achieve the 3,000RPM rotor speed for 50Hz mains frequency.

Generator Specifications
Generator Specifications
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Hydraulic Generators, Missing Valves & Liars

While sourcing the main propulsion hydraulic system for nb Tanya Louise in the summer, we thought that it would be convenient to have an on board generator that didn’t require dragging off the boat & highly explosive petrol to operate.

As the hydraulics were already being fitted, we decided to add a hydraulically driven generator to solve this issue.

And this is where the problems began…

 

We were referred to Mike Webb of hydraulicgenerators.co.uk to supply the equipment required for this part of the project, this was to include the alternator itself, hydraulic motor to drive the alternator, the required adaptor plates to mate the motor to the generator head & a control valve block to regulate the oil flow & pressure to the motor.
After a phone call to Mike on 16-07-2013 to discuss our requirements, we settled on a system. I received the following E-Mail the next day from Mike:

Good morning, reference our conversation, Martin from BSP has given me details as to what he will be supplying, on that basis and in light of the special price I have offered, this is what I propose to supply,

 

1 off New 8kVa – 7kW Hydraulic driven generator 220v single phase 50hz c/w flow control valve, pressure relief valve and on/off solenoid valve,  Martin did say that the engine idle is between 1000 and 1200 rpm and  max speed is 3600 rpm, valves will be rated accordingly. I have the alternator and parts available now, in order for me to be able to offer this at a significantly discounted price of £ 1.200.00 nett, I will need to utilise the components I have in stock now, so I will need payment asap, delivery will be approx. 7 days, primarily due to the fact that the coupling is fabricated to suit, I can either deliver the unit to you when ready or BSP or hold onto it until everything else is in place.  The alternator is a Meccalte S20W that I bought for another customer a few weeks ago, but he cancelled and I don’t have, at this time, anyone else interested in it, so either I do a deal with you at the above price or wait until someone else comes along and wants the unit.

 

With regards to installation, let me know if you need any help, but it would be best to install when the engine is being installed and the rest of the system hosed up, I assume BSP will be sorting this, in which case I’ll liase with Martin.

 

I trust that this meets with your approval and look forward to hearing from you.

At this point an order was placed with Mike, & the money transferred so he could begin building the unit for us. As can be seen from the E-Mail, a lead time of 7 days was stated.

After a few phone calls over the following month, firstly being told that the custom parts to mate the generator to the motor had not come back from the engineers, I sent another E-Mail to Mike on 10-09-2013, and got no reply.
Following another phone call, I was told that the generator had been shipped, however Mike would not give me any tracking details for the shipment, and would not initially tell me who it was shipped with.

Again the generator didn’t turn up.

More phone calls ensued & I was told at this point that the shipping company had been confused by the address given, shipped back to Mike. At this point I was informed that the shipping company had actually LOST  it. Several more phone calls later I was promised that a replacement generator would now ship no later than 08-10-2013. A follow up E-Mail two days later also generated no reply.

At this point I was beginning to wonder if I would ever see the goods we had paid for, but finally a shipment arrived from Mike
~15-10-2013, over TWO MONTHS after our promised delivery date. However, even having been delivered, all was not well with the goods.

Generator Pallet
Generator Pallet

Above is the generator supplied. No mounting bracket, no integrated valve block, in short, nothing like what was described in Mike’s documentation & website. The original documentation is available here for reference: [download id=”5564″]

The valve block supplied was this:

Valve Block
Valve Block
Missing Solenoid Valve
Missing Solenoid Valve

Flow control: check.
Pressure relief: check.
Control solenoid valve: Gaping hole….

As can be seen, there is an open port on the side of the valve block. This is where the ON/OFF control solenoid valve is supposed to be located.
After several more unanswered E-Mails & phone calls, I had to get somewhat more forceful in my messages, as now Mike had begun outright lying about what was specified in the original order. In which that there was no solenoid valve required. So the following E-Mail was sent 21-10-2013:

Mike,

Having had a conversation with Martin, about him attempting to contact you regarding what you have supplied to us, I need this resolving ASAP now, as I am being held up by the fact that there is an open port on your valve block where the solenoid control valve is supposed to be located.

As it stands the valve block & therefore the generator you have supplied to us is useless for it’s intended purpose & I will be seeking legal advice on this matter if a resolution cannot be made this week, considering you have not replied to any E-Mail I have sent since the unit’s massively delayed arrived.

In your original correspondence it is certainly indicated that this valve was to be fitted, which was also Martin’s instruction to you.  

I await your expedient response.

This threat of legal action actually spurred a response from Mike, who finally replied with the following on 25-10-2013:

Ben,

 

Sorry about all this, I have been away and down with a bug for the last week, I will sort this today and will have the required parts shipped to you on Monday for Tuesday delivery.

 

Regards

Mike

Another promise of a delivery date, so I waited a little longer, until the Friday of that week. Still no delivery. No surprise there then.
(I didn’t believe the story about illness either).

At this point I again attempted contact, but got nowhere, even with legal threats. So I’ve given up completely on this & been forced to source the parts elsewhere at extra cost.

This company is not the one to go to if you require a hydraulic generator unit for any application, as you’d be lucky to get any part of what you order on time, if at all.
Operations are run by an all out liar who seems to be happy to accept money but not ship the goods that had been paid for.

Mike having explained to me that the shipping company had lost a generator, and he would have to build me another one to replace it also does not make sense, as in the initial phone call & mail he stated that the Meccalte generator that we eventually received was a single unit that was specially ordered for another client, and the factory build date on the unit certainly gave away the fact that the generator head had been sat around for some considerable time before I came along & made a purchase.

Hopefully this post will get a high Google ranking, to ensure that anyone else who happens to be looking for a similar piece of equipment does not have the misfortune to trust this man.
We were referred to him on good faith & unfortunately in this case it did not go well.

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Datakom DKG-171

Front
Front

Here is a teardown of the Datakom DKG-171 generator transfer controller. Here is the front of the unit, with the pictogram of the system, the indicator LEDs & the generator test button.

 

Rear
Rear

The rear of the unit features the connection points for the mains, generator & generator control I/O.

PCB Rear
PCB Rear

Rear of the PCB with the control relays. The two larger relays switch in the remote contactors to switch the mains supply over between the grid & the generator, while the smaller relay switches 12v power out to a terminal to automatically start the generator.

PCB Front
PCB Front

Front of the PCB with the control logic & main PIC microcontroller.

 

 

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Wearable Raspberry Pi – Some Adjustments

USB Hub
USB Hub

As the first USB hub I was using was certainly not stable – it would not enumerate between boots & to get it working again would require waiting around 12 hours before applying power, it has been replaced. This is a cheapie eBay USB hub, of the type shown below.

These hubs are fantastic for hobbyists, as the connections for power & data are broken out on the internal PCB into a very convenient row of pads, perfect for integration into many projects.

Breakout Hub
Breakout Hub

I now have two internal spare USB ports, for the inbuilt keyboard/mouse receiver & the GPS receiver I plan to integrate into the build.

These hubs are also made in 7-port versions, however I am not sure if these have the same kind of breakout board internally. As they have the same cable layout, I would assume so.

 

Connector Panel
Connector Panel

Here is a closeup of the back of the connectors, showing a couple of additions.

I have added a pair of 470µF capacitors across the power rails, to further smooth out the ripple in the switching power supply, as I was having noise issues on the display.

Also, there is a new reset button added between the main interface connectors, which will be wired into the pair of pads that the Raspberry Pi has to reset the CPU.
This can be used as a power switch in the event the Pi is powered down when not in use & also to reset the unit if it becomes unresponsive.

 

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Wearable Raspberry Pi Part 2.5 – Battery Pack PCM

Battery PCM
Battery PCM

The final part for the battery pack has finally arrived, the PCM boards. These modules protect the cells by cutting off the power at overcharge, undercharge & overcurrent. Each cell is connected individually on the right, 12v power appears on the left connections. These modules also ensure that all the cells in the pack are balanced.

 

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Wearable Raspberry Pi SMPS Modifications

SMPS Mods
SMPS Mods

A few modifications were required to the SMPS modules to make the power rails stable enough to run the Pi & it’s monitor. Without these the rails were so noisy that instability was being caused.

I have replaced the 100µF output capacitors & replaced them with 35v 4700µF caps. This provides a much lower output ripple.

There are also heatsinks attached to the converter ICs to help spread the heat.

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Wearable Raspberry Pi Part 2 – Power Supply

All Fitted
All Fitted

Progress is finally starting on the power supply unit for the Pi, fitted into the same case style as the Pi itself, this is an 8Ah Li-Poly battery pack with built in voltage regulation.

Regulator Boards
Regulator Boards

Here are the regulators, fixed to the top of the enclosure. These provide the 12v & 5v power rails for the Pi unit, at a max 3A per rail.

Battery Pack
Battery Pack

In the main body of the case the battery pack is fitted. This is made up of 4 3-cell Li-Poly RC battery packs, rated at 2Ah each. All wired in parallel this will provide a total of 8Ah at 12.6v when fully charged.

Powered Up
Powered Up

Here the regulators are powered up from a 13v supply for testing. I have discovered at full load these modules have very bad ripple, so I will be adding extra smoothing capacitors to the power rails to compensate for this.

I/O
I/O

Here are the connectors on the top of the unit, outputting the two power rails to the Pi & the DC barrel jack that will be used to charge the pack.

 

 

 

 

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He-Ne Laser

He-Ne Laser Mount
He-Ne Laser Mount

Having had a He-Ne laser tube for a while & the required power supply, it was time to mount the tube in a more sturdy manner. Above the tube is mounted with a pair of 32mm Terry Clips, with the power leads passing through the plastic top. The ballast resistor is built into the silicone rubber on the anode end of the tube. (Right).
Output power is about 1mW for this tube, which came from a supermarket barcode scanner from the 90’s. The tube is dated August 1993 & is manufactured by Aerotech.

Internals
Internals

Inside the box is the usual 2.2Ah 12v Li-Po battery pack & the brick type He-Ne laser supply. The small circuit in the centre is a switchmode converter that drops the 12v from the battery pack to the 5v required for the laser supply.

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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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DIY Valve Amplifier – Part 1 – Amplifier Section

Components
Components

Here are a few details of a valve amplifier I am building, using the valve related parts from a 1960’s reel to reel tape recorder.

This amplifier is based on an a Mullard ECL82 triode/pentode valve, with an EM84 magic eye tube for level indication.

Beginnings Of The Amplifier
Beginnings Of The Amplifier

Here the first components are being soldered to the tags on the valve holder, there are so few components that a PCB is not required, everything can be rats-nested onto the valve holders.

Progress
Progress

Progressing with the amplifier section componentry, all resistors are either 1/2W or 2W.

Valve Sockets Fitted
Valve Sockets Fitted

Here the valve holders have been fitted, along with the output transformer, DC smoothing capacitor & the filament wiring, into the top of the plastic housing. At this point all the components that complete the amplifier section are soldered to the bottom of the right hand valve holder.

Wiring
Wiring

Starting the wiring between the valves & the power supply components. The volume control pot is fitted between the valve holders.

Valves Test Fit
Valves Test Fit

The valves here are test fitted into their sockets, the aluminium can at the back is a triple 32uF 250v electrolytic capacitor for smoothing the B+ rail.

Amplifier Section First Test
Amplifier Section First Test

First test of the amplifier, with the speaker from the 1960’s tape recorder from which the valves came from. the 200v DC B+ supply & the 6.3v AC filament supply is derived from the mains transformer in the background.

Magic Eye Tube Added
Magic Eye Tube Added

Here the magic eye tube has been fitted & is getting it’s initial tuning to the amplifier section. This requires selecting combinations of anode & grid resistors to set the gap between the bars while at no signal & picking a coupling RC network to give the desired response curve.

Final Test
Final Test

Here both valves are fitted & the unit is sitting on it’s case for final audio testing. the cathodes of the ECL82 can be clearly seen glowing dull red here.

 

In the final section, I will build a SMPS power supply into the unit to allow it to be powered from a single 12v DC power supply.

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SEPIC Regulator Test Rig

Regulator Hookup
Regulator Hookup

Here’s the regulator hooked up with test clips, on the right is the supply from the ultracapacitor bank, while on the left is the output, feeding a 2.3A brushless fan as a test load.

These regulators do get warm, even with no load, with a 2.3A load on the output, the temperature stays warm to the touch.

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Brightwell Brightstar II BSL4 Dosing System

Overview
Overview
Overview

Here is an old chemical dosing system for industrial washing machines. These units are 4-pump models, with dual pumpheads. The motors are reversed to operate alternate pumps in the same head.

Label
Label

From 2006, this is a fairly old unit, and made in the UK.

CPU Board
CPU Board

Main controller PCB, with interface to the power electronics via the ribbon cable, an external serial port for programming to it’s left. Powered by an ST microcontroller. The LCD is below this board.

PCU & Driver PCBs
PCU & Driver PCBs

Main power supply, sense input & motor driver boards. The PSU outputs +5v, +12v & +24v. The inputs on the lower left connect to the washing machine & trigger the pumps via the programming on the CPU. The motors are driven by L6202 H-Bridge drivers from ST.

Motor Assembly
Motor Assembly

Motor & gearbox assembly on the back of the pumphead. These are 24v DC units with 80RPM gearboxes.

UPDATE:
As it seems to be difficult to find, here is the user manual for this unit:
[download id=”5557″]

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Raspberry Pi GPIO Experiment Board Improvements

First Mods
First Mods

Here are the first set of mods & improvements to the RasPi Experiment board. Instead of the solder-point experiment space, I have added a standard mini-breadboard, even though it’s a little too long to fit on the board properly.

In the DIP breakout, is a MAX232 TTL-RS232 interface IC, useful for interfacing directly to the Pi’s UART, made available on the GPIO breakout. I will be hardwiring the MAX232 IC into the GPIO port, & fitting headers to the relevant pins on the IC breakout to make interfacing to the Pi easier.

All the MAX232 requires to operate are a 5v supply & 4 1µF capacitors.

The new TO220 device next to the breadboard is a TIP121 darlington power transistor.This is rated at 80v 5A continuous. Useful for driving large loads from a GPIO output.

 

More to come soon!

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AutoFace HID Ballast & Bulb

Ballast
Ballast

I bought one of these cheap HID kits from eBay to build a high-brightness work light that I could run from my central 12v supply.

At £14.99 I certainly wasn’t expecting anything more than the usual cheap Chinese construction. And that’s definitely what I got 😀

Potted PCB
Potted PCB

The casing is screwed together with the cheapest of screws, with heads that are deformed enough to present a problem with removal.

As can be seen here, the inside of the unit is potted in rubber compound, mostly to provide moisture resistance, as these are for automotive use.
The ballast generates a 23kV pulse to strike the arc in the bulb, then supplies a steady 85v AC at 3A, 400Hz to maintain the discharge.
This module could quite easily be depotted as the silicone material used is fairly soft & can be removed with a pointed tool.

 

Hi-Lo Bulb Assembly
Hi-Lo Bulb Assembly

Here is the bulb removed from it’s mount. Under the bulb itself is a solenoid, which tilts the bulb by a few degrees, presumably to provide dim/dip operation for a headlight. This functionality is superfluous to my requirements.

Bulb
Bulb

Closeup of the arc chamber of the bulb.

 

 

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Zebra P330i Card Printer

Front
Front

This is the teardown of a Zebra P330i plastic card printer, used for creating ID cards, membership cards, employee cards, etc. I got this as a faulty unit, which I will detail later on.
This printer supports printing on plastic cards from 1-30mils thick, using dye sublimation & thermal transfer type printing methods. Interfaces supplied are USB & Ethernet. The unit also has the capability to be fitted with a mag stripe encoder & a smart card encoder, for extra cost.

Print Engine
Print Engine

 

 

 

 

On the left here is the print engine open, the blue cartridge on the right is a cleaning unit, using an adhesive roller to remove any dirt from the incoming card stock.
This is extremely important on a dye sublimation based printing engine as any dirt on the cards will cause printing problems.

Cards In Feeder
Cards In Feeder

 

Here on the right is the card feeder unit, stocked with cards. This can take up to 100 cards from the factory.
The blue lever on the left is used to set the card thickness being used, to prevent misfeeds. There is a rubber gate in the intake port of the printer which is moved by this lever to stop any more than a single card from being fed into the print engine at any one time.

Card Feeder Belt
Card Feeder Belt

 

 

 

Here is the empty card feeder, showing the rubber conveyor belt. This unit was in fact the problem with the printer, the drive belt from the DC motor under this unit was stripped, preventing the cards from feeding into the printer.

Print Head
Print Head

 

 

 

Here is a closeup of the print head assembly. The brown/black stripe along the edge is the row of thin-film heating elements. This is a 300DPI head.

 

Print Station
Print Station

 

 

 

This is under the print head, the black roller on the left is the platen roller, which supports the card during printing. The spool in the center of the picture is the supply spool for the dye ribbon.
In the front of the black bar in the bottom center, is a two-colour sensor, used to locate the ribbon at the start of the Yellow panel to begin printing.

LCD PCB
LCD PCB

 

 

Inside the top cover is the indicator LCD, the back of which is pictured right.
This is a 16×1 character LCD from Hantronix. This unit has a parallel interface.

LCD
LCD

 

 

 

 

Front of the LCD, this is white characters on a blue background.

Roller Drive Belts
Roller Drive Belts

 

 

 

Here is the cover removed from the printer, showing the drive belts powering the drive rollers. There is an identical arrangement on the other side of the print engine running the other rollers at the input side of the engine.

Mains Filter
Mains Filter

 

 

 

Here the back panel has been removed from the entire print engine, complete with the mains input wiring & RFI filtering.
This unit has excellent build quality, just what is to be expected from a £1,200+ piece of industrial equipment.

Main Frame With Motors
Main Frame With Motors

 

 

The bottom of the print engine, with all the main wiring & PCB removed, showing the main drive motors. The left hand geared motor operates the head lift, the centre motor is a stepper, which operates the main transmission for the cards. The right motor drives the ribbon take up spindle through an O-Ring belt.

Feeder Drive Motor
Feeder Drive Motor

 

 

 

Card feeder drive motor, this connects to the belt assembly through a timing belt identical to the roller drive system.
All these DC geared motors are 18v DC, of varying torque ratings.

Power Supply
Power Supply

 

 

 

Here is the main power supply, a universal input switch-mode unit, outputting 24v DC at 3.3A.

PSU Label
PSU Label

 

 
PSU info. This is obviously an off the shelf unit, manufactured by Hitek. Model number FUEA240.

Print Engine Rear
Print Engine Rear

 

 

 

The PSU has been removed from the back of the print engine, here is shown the remaining mechanical systems of the printer.

Print Engine Components
Print Engine Components

 

 
A further closeup of the print engine mechanical bay, the main stepper motor is bottom centre, driving the brass flywheel through another timing belt drive. The O-Ring drive on the right is for the ribbon take up reel, with the final motor driving the plastic cam on the left to raise/lower the print head assembly.
The brass disc at the top is connected through a friction clutch to the ribbon supply reel, which provides tension to keep it taut. The slots in the disc are to sense the speed of the ribbon during printing, which allows the printer to tell if there is no ribbon present or if it has broken.

RFID PCB
RFID PCB

Here is a further closeup, showing the RFID PCB behind the main transmission. This allows the printer to identify the ribbon fitted as a colour or monochrome.
The antenna is under the brass interrupter disc on the left.

I/O Daughterboard
I/O Daughterboard

 

 

 

 

 

The I/O daughterboard connects to the main CPU board & interfaces all the motors & sensors in the printer.

Main PCB
Main PCB

Here is the main CPU board, which contains all the logic & processing power in the printer.

CPU
CPU

 

 

 
Main CPU. This is a Freescale Semiconductor part, model number MCF5206FT33A, a ColdFire based 32-bit CPU. Also the system ROM & RAM can be seen on the right hand side of this picture.

Ethernet Interface
Ethernet Interface

 

Bottom of the Ethernet interface card, this clearly has it’s own RAM, ROM & FPGA. This is due to this component being a full Parallel interface print server.

Ethernet Interface Top
Ethernet Interface Top

 

 

 

 
Top of the PCB, showing the main processor of the print server. This has a ferrite sheet glued to the top, for interference protection.

 

 

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Camcorder CRT Viewfinder

CRT Assembly
CRT Assembly

Here are the viewfinder electronics from a 1984 Hitachi VHS Movie VM-1200E Camcorder. These small CRT based displays accept composite video as input, plus 5-12v DC for power.

Screen
Screen

Here is the front face of the CRT, diameter is 0.5″.

Power Board
Power Board

Closeup view of the PCB, there are several adjustments & a pair of connectors. Socket in the upper left corner is the power/video input. Pinout is as follows:

  1. Brown – GND
  2. Red – Video Input
  3. Orange – +12v DC
  4. Yellow – Record LED
The potentiometers on the PCB from left:
  1. H. ADJ
  2. V. ADJ
  3. BRIGHT
  4. FOCUS
PCB Part Number reads: EM6-PCB
This unit utilises the BA7125L deflection IC.
Solderside
Solderside
Reverse side of the PCB, very few SMT components on this board.
Tube Assembly
Tube Assembly
Here is an overall view of the CRT assembly with scan coils. Tube model is NEC C1M52P45.
Electron Gun
Electron Gun

Closeup view of the CRT neck, showing the electron gun assembly.

 

CCTV Camera
CCTV Camera

The old CCTV camera used to feed a composite signal to the CRT board. Sanyo VCC-ZM300P.

CCTV Camera Connections
CCTV Camera Connections

Connections at the back of the camera. Red & Black pair of wires lead to 12v power supply, Green & Black pair lead to the CRT board’s power pins. Seperate green wire is pushed into the BNC video connector for the video feed. video ground is provided by the PSU’s ground connection.

Connections
Connections

Finally the connections at the CRT drive board, left to right, +12v, Video, GND.

Screen Operation
Screen Operation

Display taking video signal from the CCTV camera.

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PSi 150 Power Inverter

Front
Front

This is a small 120W power inverter, intended for small loads such as lights, fans, small TVs & laptop computers.

End Cover
End Cover

End cover of the unit, 12v DC input cord at the top, power switch & indicator LEDs at the bottom.

Mains Output
Mains Output

Opposite end of the unit, with the standard 240v AC 50Hz Mains output socket.

Cover Removed
Cover Removed

Cover removed from the top of the unit. Main power transformer is visible in the centre here, MOSFET bank is under the steel clamp on the left, the aluminium case forms the heatsink.

PWM Controllers
PWM Controllers

On the right is a KA3525 switchmode PWM controller & on the left is a LM324N quad Op-Amp IC. The buzzer on the far left is for the low battery warning.

PCB Removed
PCB Removed

PCB removed from the casing, with the MOSFET bank on the right hand side. Two potentiometers in the centre of the board tweak the frequency of the switcher & the output voltage.

 

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455nm Laser Head

Aixiz Module
Aixiz Module

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
Connection

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.

Beamshot 1
Beamshot 1

Looking down the beam, laser is under the camera. Operating around 1.2W here

Beamshot 2
Beamshot 2

Camera looking towards the laser. Again operating at ~1.2W output power.

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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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Belkin F5U021 4-Port USB Hub

Top
Top

This is an old USB 1.1 hub that was recently retired from service on some servers. Top of the unit visible here.

Bottom Label
Bottom Label

Bottom label shows that this is a model F5U021 hub, a rather old unit.

PCB Front
PCB Front

PCB is here removed from the casing, Indicator LEDs along the bottom edge of the board, power supply is on the left. Connectors on the top edge are external power, USB host, & the 4 USB outputs. Yellow devices are polyswitch fuses for the 500mA at 5v each port must supply.

USB Hub IC
USB Hub IC

This is the USB Hub Controller IC, which is a Texas Instruments TUSB2046B device. Power filter capacitors next to the USB ports are visible here also, along with 2 of the polyswitches.

Power Supply
Power Supply

The power supply section of the unit, which supplies regulated 5v to the ports, while supplying regulated 3.3v to the hub controller IC. Large TO-220 IC is the 5v regulator. Smaller IC just under the power selector switch is the 3.3v regulator for the hub IC. The switch selects between Host powered or external power for the hub.