Curiosity Killed the Human...
There is always something nice about coming over strange boxes in boxes. And this little device was the same, but it gave me more questions than answers.
First off, a word or caution.
Never plug something old directly in the main before giving it a good visual inspection first!
In this case there are so many things that are crying out ‘bin it’, but I am a little curious and I do love a mystery.
First off, the things that shout out ‘Stay Away’!
The box is covered in rust, and although that alone should stop you from plugging this unit in the mains to see what it can do, but for me the big ‘no-no’ is the use of ‘Bell Wire’ as a mains lead, certainly not a good thing on a good day.
This unit is disgusting though, not been cleaned in ages and although held together by rusted screws, it did take me a further 2 days to slowly break the threads to get the front panel off using WD40.
I noticed that for some reason the decals on the front panel would show up better through the photos than they do in real-life, so I snapped away to see if this would give me a clue as to what this unit was.
My thoughts a ‘Clock’ of some sort.
It took ages for WD-40 to even give me a hint that the screws would come out, the slotted screws had very soft heads and you could feel that they were just about to give way, so I took my time with this, and very slowly they loosened off.
The first look at the insides certainly proved my point, the large Capacitor was not held in place at all and one of the legs that went to the circuit bord was broken off and could have easily touched the metal case at any time.
If I was going to do a full restoration, i.e., if this was a radio that I had an interest in keeping that is. I would at this stage take a million photos before touching anything closely followed by starting to decipher the wiring and the PCB’s, normally in any case, my first workings out would not be correct, and I would need to re-work the schematic as I went along.
But I can already see from just the initial look that this was a clock or a time piece of some sort, and I can also see that we have quite a few broken connections, it may not have been deadly but with a big smoothing capacitor such as this would still hold a good amount charge when connected to at list give you a dam good scare if grounded.
After a break and coming back to this as it was taking up valuable space I also. Started to notice other things, mainly that a few of the switches were basically just there for show as they had no electrical connection at all to the rest of the kit, with no signs of solder ever going near them – Oversight maybe?
10 out of 10 for crudeness, the small Veroboard is soldered in place and this is also an electrical connection, obviously a ground for the oscillator board, but even so, a very crude construction, but that said I am sure at the time it did the job.
Some of the connections are a bit hap hazard, no wonder there are a few wires broken off, and the lack of wire management is also a bit scary.
I have a clue to who created this in where I got it from, the person in question was a very good engineer for the local radio station on the island at the time and was also quite a bit busy, I am sure that this did the job it was intended for, but even so, it’s still a bit of an oddity.
It was obvious from the start that I was not going to restore this unit, it is basically no worth the time it would take, especially when I have much more pressing things to do.
It has some useful parts, and they are worth more to me than the unit working.
The reason for this post was to point out though that nothing should ever be plugged in for the sake of having a plug on a bit of wire, at the most it needs putting in line with a Variac and a bulb current tester to warn of possible shorts and dangerous wiring.
Even though I have a good idea as to what this little scary box was used for it still needs to be treated with caution.
It does not matter if you know who built something and thought that ‘I trust him’ therefore I am happy to plug it in, the person in question here was a very good RF engineer and easily able to build, maintain and repair AM transmitters and associated materials, but even then, any box of tricks, you need to be cautious with. In this case it’s just a low voltage clock mechanism that at its time had a purpose, that we will never know.
If this had vacuum tubes inside of it, and the mains transformer was subsequently a lot bigger, the circuity may have also be a lot different, but vacuum tubes equal ‘Deadly Voltages normally, and in most cases can easily exceed 600v, in its present condition, plug this in and you may get a tingle if you touched the box, that tingle could give you a scare, if this was vacuum tubes though, you will easily not remember touching it.
It worries me sometimes that you see on YouTube a lot of newcomers playing with old radio equipment, and they defiantly have no clue as to what certain equipment is, it fills a spot, but from the questions they are or comments hey leave, you know automatically that they do not really have a clue what they are about to do, and much more important than that, they have no idea of just how deadly working on some equipment can be.
You need to respect anything that comes with a plug that connects you to 240v, mains will normally shock you and give you a good twinge of scariness. Put your bare fingers into a old vacuum tube radio and touch something by mistake – That ‘WILL’ kill you.
There are many things us who enjoy restoring old radios come across to slow us down a little, thankfully this black rubber paint is not one of them, I could just through this in the ultrasonic cleaner and let that do it’s trick, older stuff can normally take being submerged in liquid and come out basically read to go, but anything with IC’s is normally ‘Hit and Miss’.
If I was going to restore this item, I would have taken the risk that everything underneath that black crap is still readily available, worse case IC and transistors have been replaced, and this could mean that as you draw up the schematic diagram you may need to add components or change the values on items to get the same results out.
It should be noted that there are a lot of components that are no longer manufactured and ‘New/Old Stock’ can be very unreliable, RAM chips used in the lovely old 8-bit computers that we grew up with are notoriously prone to breaking down, thankfully old 8-bit computers are basically a giant logic board and very easy to diagnose with just a logic probe, but a lot of proprietary IC’s bring a whole new level of hardship into repairing old radios, for instance the CPU’s often used in early Yaesu Radios are not only not available now, and there is not a replacement that will just fit in the socket and do the job, and entire separate PCB has to be made with loads of parts, just to replace what was 1 IC.
It is always fun, but old vacuum tube equipment, is actually a lot easy to repair, and restore than more modern items, the circuits are normally very easy to work out if schematics are not available, and even though most of the vacuum tube manufacturers have either gone or just do not make tubes anymore, there are a infinite supply of tubes available in private hands, sadly though idiots out there are basically getting very greedy in what they term are ‘Rare’ components and add silly prices to anything old, assuming that it is worth a lot more than it actually is, but there are still the odd good supplier out there that will happily pass on old stock at a friendly price.
I really have gone way over the top here.
I was just wanting to add this post to warn people that do not understand what they have in front of them that by just plugging something in and seeing if it will light up, is very fool hardy and can be lethal.
Another also very important and very overlooked subject, is ‘earths’!
You need to be very wary of earths, it makes sense that all items nowadays are earthed, but this also brings up a much-overlooked problem, that Oscilloscope that you love is also earthed, and the probs that you are presently using are actually normally attached to ground, i.e. earth, and can often be the cause of you having to replace your scope after inadvertently sending voltages from what you are testing through the ground connection to the test equipment attached, and suddenly your very costly item is now just a ‘doorstop’.
Make sure that when testing anything a ‘Isolation Transformer’ is used, but even just buying these cannot help you sometimes, not all Isolation Transformers are actually fully isolated so to speak, check that they are earth isolated as well, a lot have a detachable earth hidden inside them to enable this option.
So, without ever plugging the unit in, this will sadly get butchered, stripped and catalogued for use in future projects or repairs.
The IC’s if socketed will be kept, soldered in ones are normally ditched along with any passive components such as the resistor and capacitors. The switches are the only items worth keeping in this case.
Not everything is worth restoring!
If this was an old radio, covered in rust, it might be a different decision, but even then, just having a mains lead attached does not mean that t s automatically safe to plug it in and see if it lights up. It may just light up, and there you are leaning over to put your hands on the metal case to move it a bit to get a better view of your new radio that you found at the tip or were given – that just may be the last thing that you ever do.