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T i m T i m is offline
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Default Is there any "market" for old electronics, even for free?

On Thu, 27 May 2021 10:16:28 -0700 (PDT), "Peter W."
wrote:

But, I agree that for the most part, many things find their way to landfill due to very minor failures combined, the rarity of good repair options,

I like the idea of the 'repair workshops' where people bring stuff
along and volunteers try to fix it for the cost of any parts and a
charity donation or similar?


This goes to a post I made some years ago when a British gentleman asked about initiating a 'repair cafe. I have been doing this along in the vintage electronics hobby for well over 20 years now


Excellent.

- so my 'rules' are as follows:

I participate in the occasional radio-club related repair clinic, and give one twice a year in Kutztown, teaching basic diagnostic and repair techniques for vintage radios and electronics from the 1920s to approximately the 1990s. There are some basic rules for the protection of the clinician and the 'customer'.

a) Do not take money. Do not imply Fee-for-Service. The moment money is taken, there is an expectation of professionalism and expertise that conveys a level of liability.


Understood. I have often done the same for friends of friends (who may
not already know 'the deal'). Best endeavours, no guarantees and no
liability accepted etc.

b) Make it clear that you are doing this as a hobby, and that you are demonstrating technique and skills that may be useful to the customer in their future endeavors along the same hobby-related lines.


Check.

c) If parts are to be replaced, those parts *must* be obtained and supplied by the customer. Pointing to possible sources is OK, as long as you are able to point to more than one.


Makes sense. A mate used to work that way in his car garage.
Mainstream new parts from manufacturer or factor or parts supplied by
the customer (where no liability for any consequences relating from a
failure of such excepted).

d) If power must be applied to an item during the process, the source must be isolated, and you must explain to the customer the reasons for it, and advise him/her why this is so.


Are we talking auto/isolation-transformers here?

e) Kluge repairs left in place are not acceptable, full stop. For instance, if one jumps out a damaged 'fuse resistor' to determine whether replacing it is worthwhile and the customer does not have the actual replacement - you may go as far as to suggest that the item is repairable - but not here, and not without the proper parts. Remove the jumper.


Good example. A Freecycle Colour Laser printer I picked up had two
(identical?) thermal switches in series in the fuser heater supply,
presumably so that there could be a 'failsafe' switch in case the one
became locked shut. I 'temporarily' shorted out the faulty one (and
applied a notice on the body of the printer to that effect) and it
remains so, but I never left the printer on and it's currently unused
in any case. I wouldn't have left it like that if it was going out of
my hands.

Whether or not an organization has "insurance cover', should there be an unfortunate event, the individual tech involved will remain involved whether liable for actual damages or not. And whereas most individuals are sincere and mean no harm, a fire, shock or other occurrence will change even the most gentle person.


Agreed. A neighbour asked me if I could show him how he could service
the brakes on his own motorbike and because I was aware of his
complete lack of wrenching skills (and tools, experience, interest,
patience), I declined.

I will teach technique, and I will show individuals how to make their own basic repairs such as re-capping, cleaning and similar. I will point them to books, manuals and sources. But in a situation where one is dealing with the *GENERAL PUBLIC*, I will take nothing for granted.


Wise words.

I often have to remind myself that some people don't have the same
range of skills as me (/us?). I'm only a 'Jack of all trades' (when
that is mostly anything practical that doesn't require lots of
training, (expensive) specialist tools or a specific mindset, like
plastering or coding) but was born into an era when 'make do and mend'
was still just about current and whilst I was always looked after by
my parents when it came to important stuff (school equipment etc), I
was generally left to sort out my own stuff, like bicycles, mopeds,
motorcycles and cars.

I also had an interest in 'things' from an early age and would
regularly open stuff up or take faulty things to bits to learn how
they worked.

Along those lines I was also often given old electrical stuff, radios
and record players by friends and family (mostly faulty at some level)
and would often repair them. A broken drive belt, a broken wire, blown
fuse or even a transistor shorted to the (earthed) can. ;-)

So I often assume everone else can learn to do the same range of
things (if I can, so can they ...) but that isn't always the case (it
seems).

A mate is also running Home Assistant home automation software to
mostly do things around his fish tanks and recently I dropped off all
the parts for him to assemble such a project (a CO2 controller [1])
and had overseen him configuring / programming the ESP32 board and
Home Assistant integration remotely over Teamviewer.

I setup the same thing here, tested it and sent him a picture.

His tasks. Solder some header pins onto a uUSB board (1x5, it breaks
out a uUSB connector), solder some header pins onto an ESP32 (2 x 19),
jumper 2 wires between uUSB board and 4ch opto isolator board (2
wires), jumper the output of the opto to the ESP32 (3 wires).

I'd provided him the circuit diagram for the opto board, the pinout of
the ESP32 and plenty of verbal guidance as to the goals.

Phone call the next day:

'I'm getting not 5V out of the uSB boards' (I had given him two boards
in case he screwed one up). I took him though various steps and it
turned out to be a dirty connection on his DMM.

Then it was a misconnection between uUSB board and input to the opto
(Gnd Gnd, 5V to 'NC'!, 5V wire then moved to Input1).

Then there was a misconnection between opto and ESP32 (Gnd from opto
connected to a data pin next to Gnd pin on ESP32).

Once they were all resolved, it all worked as planned. ;-)

He actually added a Dallas '1 wire' temperature sensor himself and to
the right pins but it didn't work, turned out to *need* the / a pullup
resistor (sometimes doesn't, I was trying to keep it simple for him).
;-)

My point was that I thought he 'understood' what I was telling him but
it may well have been that he didn't, knew there was no point in
asking as he still wouldn't understand or remember and so let it wash
over him knowing I was at the end of the line for guidance, as / when
he needed it.

Cheers, T i m

[1] He has an expensive CO2 controller that monitors the CO2 level in
a fish tank and then turns on a mains powered solenoid to allow Co2 to
bubble though the water for the plants during the day. He didn't want
to waste CO2 gas during the night. I didn't want him playing with 240V
or tampering with the existing controller so he powered the solenoid
from a TP-Link WiFi smart socket controlled by Home Assistant and we
used a basic phone charger plug to supply 5V to the ESP32 input as a
binary trigger to indicate the CO2 controller was calling for CO2, but
HA would inhibit that via a condition in an automation between the
hours of 22:00 and 08:00.