Junkbox engineering & home made development tools - Why?

[RichTheDude]

I know its common place still (“Can you help me make this out of random component x which has no datasheet”) but I no longer do it anymore. In the past I have made my own PIC programmers ( parallel, serial, and a home brew serial ICD2), rewound transformers, made my own FPGA and CPLD download cables, and generally made do with what I had in my collection of junk.

I used be particularly bad with development tools, as can be seen above. I no longer bother making my own tools/or doing junk box engineering (for about 8 years now!), and to be honest I am glad. I buy the proper tools and parts for the job, and life is so much easier – it has stopped me wasting so much time doing boiler plate engineering just to allow me to work on the project.

Not only that but programmers and JTAG leads can brought very cheaply now - so there is not much of a cost benefit either. JTAG leads even a few years ago was £70 plus (parallel), with USB being even more expensive. You pick up Chinese USB clones for under £20 now – is a night or two of hassle and bodging worth £20?

Same with junk box engineering. For a quick dirty test it is ok, but for anything serious I think it’s a lot easier, and a lot better to buy the component you actually want to use in your design. Saves so much hassle (and more importantly time!).

Share your thoughts

 

[MrAl]

Hi,

Way back when i built my own test equipment...a frequency counter for example that took hours to build, simple design yet lots of connections to do by hand.

Yes it takes a lot of time to do this stuff. Some of the equipment is very expensive though so then it makes sense.

 

[RichTheDude]

Some equipment I still think it warrants self build (say a spectrum analyser, frequency standard or a home brew VNA - these are still horrendously expensive! ) but the same thing I said about JTAG leads and μC programmers applies to frequency counters these days.

I brought a Rubidum standard module last year off ebay (£40 and made a proper frequency standard instrument with it - 50 ohm drivers, and dividers for 5 and 2.5 MHz). Cost me about £75 in total - they sell for about £500 second hand. Apart from fairly specialist instruments, I think my point still stands.

You can get 2.4 GHz frequency counters for under £55. Granted it’s probably just a fast (P)ECL divider and a PIC (externally clocked timer - they can run upto 60 MHz according to some projects) but again at that money it would be a lot of hard work to compete purely on cost, let alone factoring in your time. A decent instrument case alone in the UK can set you back £20 up easily.

 

[Mikebits]

I agree, it is usually cheaper to buy than make thing as you have mentioned.

 

[Bob Scott]

I guess you need to enjoy your hobby as you like. Some people like building their own projects and sweating the minor details. It gives them experience and uses up leasure time. Some hobbyists enjoy making designs of their own and get a feeling of accomplishment. I enjoy the exercise of researching parts and designing new types of circuitry and electromechanical stuff, but I rarely build stuff anymore.

If you don't enjoy building it, then don't build it.

 

[canadaelk]

50 years ago, as an apprentice, I built 2 oscilloscopes (single channel with tubes). There was no way I could have afforded a purchase. Since than, I built many more pieces of test and (primarilly) audio equipment. The advent of sophisticated PCB design software and, later, inexpensive or free modelling software changed so many things
I now rather restore an old piece of gear (I'd do Healey 2000s if only I still had a garage). But I still build stuff because I enjoy the experiences of investigating, learning, bulding, testing and all the bragging rights that go with it! E

 

[reubenT]

the education and experience gained from junk box construction is quite valuable, everyone should grow up poor and do it that way for awhile. However I would agree that buying the right parts and tools for the job will get something working faster when you need to be productive. Worth a lot when your trying to make a living. But if it's just a hobby, do whatever suits yer fancy. With more income to work with than I used to have I tend to buy more stuff, but still scrounge for simple things sometimes, like resistors and capacitors from all the junk electronics I've collected over the years.

 

[alec_t]

With more income to work with than I used to have I tend to buy more stuff, but still scrounge for simple things sometimes, like resistors and capacitors from all the junk electronics I've collected over the years.

Same here. Scrounging/scavenging is a difficult habit to break. Besides, I like to think I'm saving the planet by re-purposing bits 'n bobs.