Are Electronic Kits better?
Research has shown that ready made products for the electronics market are cheaper than electronic kits in most instances. Chinese importers as a whole, whether or not they use dodgy labour practices remain absolutely absorbed in being the biggest and best mass supplier globally. This does not bode well for the electronics enthusiast, or does it?
eBay is a classic innovator when it comes to looking online for kits (or finished products for that matter). The Asians absolutely rule here and why not. They have shown the innovative flair to capture the electronic kit market and to be perfectly honest, they deserve to be there. In our own research we discovered, most lagically, that the DIYer is really not interested in the finished product – he wants to learn how stuff works. Electronic kits do just that and moreso, the curious mind will always try to make it better. Need to go further – just look at the many forums covering audio or Arduino or auto electronics. What makes the electronic kit even more worthwhile is that although you may want to start from scratch electronic kit manufacturers will almost without doubt supply you with good quality components and tallying the total cost, cheaper than building only from a circuit.
Velleman Electronic Kits
A major electronic kit manufacturer is Velleman. The quality is very good and it’s very easy for the DIY’er to put together his kit electronic circuit without external help. Shipping is fairly quick and import is paid upfront. Ditto the electronic kit suppliers on eBay, often the board quality is better than those already built from known manufacturers for similar products and what makes it better is that the user can modify over time. What makes it worse is totaling man hours, chassis, transformer and smoothing capacitors the kit will often cost more than the completed product.
Radio Valves or Thermionic Tubes
Something to bear in mind however, the DIYer often does not have the finances to purchase completed goods and will endeavour to find cheaper parts other than the corner reseller – often this will be eBay or a junk collector. A very good example of us not seeing this happen is in the thermionic tube electronic kit market. What happened to all the old wireless gear, audio amplifiers and receivers? Thermionic tubes (radio valves or just valves) are horrendously expensive and moreso, the output transformer for coupling the valve high input impedance to the low impedance speaker. Some DIY’ers build their own which is really a very great art – copper is expensive but it is still done pretty cheaply with home made tools.
SMD – surface mount devices
With good soldering practices mounting SMD components are no more a chore than through hole. Through hole component mounting using machines is an expensive way of doing it so in many instance the electronic manufacturer tries to stick to the SMD component which is far more easily done and cheaper than through hole manufacture which is done quite often still with manual labout. This does not affect the DIY’er but often lack of confidence may put him or her off. This should not be so. Modern tools are cheap and much better than that of thirty years back. Often the DIY’er makes his own tools. A very practical way to remove surface mount components is to use a heat gun which is temperature controlled. Mounting the heat gun upwards with the proper heat focused through an attachment quickly heats the board up to a temperature to remove faulty or incorrectly mounted SMD components without damaging the board.
RHOS – Restriction of Hazardous Substances
ROHS solder carries no lead. There have been many articles written about RHOS and the dreaded tin whisker. On many commercial products I have seen some very shoddy solder work caused by RHOS soldering which requires a much higher soldering temperature and looking at the end result, often not very professional looking, especially where large current carrying cabling has to be soldered onto the board. A typical example would be the inverter welder which may carry currents in excess of 200A.
A growth of tin on the solder joint which may lead to short circuits termed tin whiskers. Military equipment often does not utilise ROHS in the manufacture process. Most electronic kits don’t make any form of indication as to what to use – preferably go with tin/lead – it’s easier and you won’t damage your board.
RHOS soldering techniques
Needs a much higher soldering temperature and all equipment to be marked for ROHS useage only. Often the equipment is green to differentiate between the soldering stations. I find ROHS soldering a bind and personally agree with the many articles written in favour of the old tin-lead mix. My first experiences which included some ‘masters’ of the soldering station was that we burnt boards easily when adding components or removing faulty components.