Reviews of several 7.5vdc power supplies from various manufacturers. Single supplies, kits and plenty of data to help you make your choice of power supply.
Fluke DTX 1800
Owon PDS5022T Series PDS Portable Digital Storage Oscilloscope
This is a good oscilloscope for the money and ideal for home workshops and DIY electronics projects.
It comes equipped with 2 Channels, 25MHz, 100MS/s Sample Rate. You can connect to a Windows based PC via a USB cable and comes with own software.
Great beginners scope and good vale for money.
The Pace PRC 2000 Soldering Station is a first class piece of equipment for production facilities or small workshops. It has SensaTemp Control temperature management system. Ideal for SMD work and repair. Through hole system which automatically dispenses solder creams & fluxes. Also, suitable for electroplating utilising variable controlled DC pulse current.
Pace PRC 2000 Soldering Station
The Hakko Soldering Station FX 888 has been getting some great reviews recently, so I though I would include it on here. It is nicely designed and comes with temperature control and is not too expensive for such a high quality soldering iron.
Hakko Soldering Station FX 888
12V DC Power Supply
How to turn a ATX PC supply into a 12V DC Power Supply for your electronics benchtop.
There are a number of DIY USB Oscilloscope kits out there on the market at the moment. Most are pretty affordable too. We take a look at some of these and compare their features and price.
DIY USB oscilloscope kits and what to look out for
i) With any kit it is always worth checking out reviews before you buy, espcecially if it is at the more expesive end of the market. Amazon is always a good place to look for these.
ii) Are all the components to complete the kit provided or will you need to purchase some extra parts? It’s important to read the small print to make sure you are getting what you expected before you begin your DIY USB Oscilloscope project
iii) DIY USB Oscilloscope schematics – is there a full set of schematics and full set of documentation available? The last thing you wnat is a half-finished set of diy oscilloscope circuit diagrams and instructions when you begin your project. Check the manufacturer’s website and see if the drawings are available for download to get an idea of what you are getting.
iv) Firmware/software – is there good support for firmware and software. It is rare to find a product that doesn’t require regular updates to firmware and software. Check that the manufacturer provide a way of getting updates. Check their website support and download section.
DIY USB oscilloscope kit comparisons
|JYE Tech DSO 062||DPScope|
|Vertical Sensitivity||100mV/div – 5V/div||5mV/div – 1V/div|
|Max input voltage||50Vpk (x1 probe) and 500Vpk (x10 probe)||20Vpk(x1 probe) and 200Vpk(x10 probe)|
|Horizonal||0.5us/div – 10min/div||0.5us/div – 1hr/div (in datalogger mode)|
|Triggers||auto/normal/single – rising/falling edge||auto/normal/single – rising/falling edge|
|Interface||RS232 serial but there is a USB adapter available||USB|
|Price||around $60 (2012 prices)||around $45/$50 (2012 prices)|
Initial considerations for a variable bench power supply
If you are looking for a variable bench power supply for a home based workbench, there are a few basic things to consider first of all.
What size is your workbench? If space is limited, it might determine the maximum size of supply you can use. If you are considering buying other instrumentation, then you will need to take these into account too.
Stand alone or programmable variable bench power supply?
If you are happy with a stand alone supply with no programming capability, then there are plenty of budget supplies to choose from. If you want to be able to program the variable bench power supply, then you will need to be prepared to spend a bit more money. If you are going for a programmable supply, there are some which can be programmed from the front panel, but are essentially stand alone supplies. Some can be programmed by a pc or laptop via a USB interface, or a GPIB interface. GPIB is an industrial standard interface, but is the more expensive option. For the home user, a USB interface is probably a better option.
How many outputs?
Next, is to consider how many outputs you will need? It stands to reason that the more outputs, the higher the cost, however it might be cheaper to get a 2 or 4 output supply rather than fork out cash on two or even four separate supplies. Also most projects seem to follow Murphy’s law that if you think you need one of something, in the end you’ll need two! Also, another advantage of having a duel output supply is that if you need to double voltage or current, you can easily link the supplies together.
For digital electronics a fixed 5V or 3.5V supply might be sufficient for your needs. Where a variable bench power supply can be handy, is when working with analogue circuits. Many op amp circuits use a variety of voltage combinations and polarity configurations. +9V/0V +12V/-12V +15V/-15V +15V/0V.
Where a programmable supply can be really useful is providing test inputs to ADC analogue to digital converter circuits.
They can also be handy for setting bias levels as the output can easily be tweaked.
If you are only working with digital electronics, but you want a variable supply, you need to take care if using a supply with max. Voltage obove 5.5V. For analogue circuits, a dual supply with two 30V outputs should be enough for most projects. For example, you can set up one output as +15V/0V and the other as 0V/-15V and tie the two 0V connections together. This setup can be adapted for many different analogue applications.
Again this will depend on what you need for your project. For most digital circuits, anything from 100mA to 500mA should be more than enough. For analogue circuits you may need more current capability from your PSU. Amplifier projects may require more current, so 1A, 3A and 10A supplies are common. Always make sure you have some form of current protection in place, even if your variable bench power supply has current limiting. Always place an appropriately rated fuse in your circuits if you want to avoid fried chips with your fish!