What follows, are some heretical thoughts related to DIY hobby.
One of the key questions to solve in context of electronics/radio/repair as a hobby, is the available assortment of parts/details. At Soviet times, all electronic parts (then called radio details) were luxury goods. In 1970-s, while an Soviet average salary was 60 RUB, official KT315 transistor costed 4.50 while Latvian made “Selga” receiver contained 6 of these transistors at 28 RUB pricetag.
These days it is not so evident anymore, whether or not to have an assortment of electronics parts at your hamshack. Provided the parts shop is situated just in the opposite building, there is actually no need to provision parts. But if it is a 30 minutes ride away? This way, if person is not very organized (to the extent of serial killer or so) and if repair is a more frequent action than DIY, a missing resistor means 1 hour delay.
Meanwhile, it is not a secret that much experience actually comes from taking apart somebody’s else designs. Quite accidentally, this is where the most scrap yard spare parts come, too. I have repaired to earn but not anymore! Now I earn by shuffling the bits. The habit of taking designs apart and reusing the parts inside of these, has remained. The time waste associated with the measuring and organizing activity is called recreation now and is written into CV as “having a bunch of very technical hobbies” 😉 And believe or not, these parts from old devices (with a notable exclusion – electrolytes) tend to be very reliable, thnx to aging.
In Western society, another approach is possible – to buy these so called “assortments” of electronics parts from China via eBay. The planning cycle turns longer and the hit rate (e.g. having popular parts you actually need) is relatively low. Do you know, which resistor value is most popular while soldering resistors off the old Western electronical devices? Very obviously I know – it is 10 kOhm.
Thus, the main question is: how to organize the parts. It turns out, we have to divide our DIY activities into several stages. The first one is measuring the parts which I’ll cover today. The second stage is storing the parts rationally which is a separate topic.
This is my current workhorse (called ESR meter on eBay). I bought it locally as a PCB and paid double because I needed it FAST. As you see, reuse of the electrolytic capacitors is a dubious business.
However, I have to warn you – the zero force socket only will last some 5000 transistors to measure (been there). It also would be clever to open the bolts, drill holes via the PCB and install somewhat longer bolts (that forceful event is scheduled by Chinese to around 500 measurements done). My recommendation: do source a new socket today and take soldering courses meanwhile. 123111 is the order of pins in the upper row, in case of yet nobody told you. Row 2 is a full pin 2 camp.
Of course, of course … some people are only able to steal (oops, to gather everything valuable in Midland). I know. Thus read the huge manuscript of original authors here and think twice before feeding the thieves. And then, feed the thieves and possibly send a beer or a box of it to Herr Karl-Heinz and his friends .
Karl-Heinz has some valuable advices about 2.5V references that were too expensive for our Chinese friends to implement 🙂
Anyway, somewhat later within a somewhat longer planning cycle, I ordered yet another counterfeit device from eBay, this time together with a transparent box. The cost – a little less than 20EUR. As with anything of Chinese or Russian origin, some DIY has been left on the consumer.
Now let’s see what these devices are capable for. Honestly said, they mostly work. The problems arise with non-standard structures like AS431A which frequently show up in old designs and with capacitors below 26 pF.
Regarding the artefacts that Chinese ppl were unable to measure, that polite nation is using euphemisms like “4” (a great joke!). BTW, error message “5” also exist but is more rare.
While these devices are super good to resort active components (why? because they detect the type), I prefer to measure the passive components by more traditional devices:
As intel pros could deduce from the pic, I use 10x averaging. The measuring cycle is still shorter than with cheap ESR meter (9-10 sec due to the missing ads). Vice versa, ESR meters are useful if your input is unsorted (R, C, L) and you need to sort it out fast.
Е7-14 has a 4-wire connectivity to the DUT, thus one can do amazing things like measuring 2-7pF trimmer capacitor while keeping it in hand and regulating. You can do miracles like biasing a capacitor or varicap up to 120V while measuring. Oh yeah, did I mention the bestia has GPIB interface? 😉
The “immitance meter” was bought as new and unboxed when Soviets left my country and everything was for sale. I paid 10-th of my monthly salary for it which I haven’t regretted yet.
And … there exist parts that either devices cannot measure, like 10V Zeners.