At Hackaday, we comb the world of tech in search of good things to bring you. Today’s search brought up something very familiar, [Jazzy Jane] has an Advance E1 tube signal generator, the same model as the unit on the shelf above where this is being written. It’s new to her, so she’s giving it a teardown and fixing any safety issues before powering it on.

For a 70+ year old unit, the quality of these instruments was such that they remain useful and reliable to this day. Unsurprisingly a few things need looking at, such as an aged mains lead and a pair of filter caps in the power supply which haven’t aged well. These parts failed on the E1 here too, and while she’s taking the time to order appropriate replacements we have to admit to being cheapskates and robbing parts with an appropriate working voltage for ours from a nearby PC power supply.

Where this one becomes rather interesting is in an extra switch and socket. It’s a wafer switch with a load of capacitors, and the best guess is it provides some adjustability for the inbuilt audio oscillator which had a fixed frequency on stock models. This is part one of a series though, so we’re looking forward to finding out its purpose in the next installment. Take a look at the video below the break, and if that’s not enough, we seem to have had more than one piece of vintage British test equipment here of late.

The triboelectric effect is familiar to anyone who has rubbed wool on a PVC pipe, or a balloon on a childs’ hair and then stuck it on the wall. Rubbing transfers some electrons from one material to the other, and they become oppositely charged. We usually think of this as “static” electricity because we don’t connect the two sides up with electrodes and wires. But what if you did? You’d have a triboelectric generator.

In this video, [Cayrex] demonstrates just how easy making a triboelectric generator can be. He takes pieces of aluminum tape, sticks them to paper, and covers them in either Kapton or what looks like normal polypropylene packing tape. And that’s it. You just have to push the two sheets together and apart, transferring a few electrons with each cycle, and you’ve got a tiny generator.

As [Cayrex] demonstrates, you can get spikes in the 4 V – 6 V range with two credit-card sized electrodes and fairly vigorous poking. But bear in mind that current is in the microamps. Given that, we were suprised to see that he was actually able to blink an LED, even if super faintly. We’re not sure if this is a testament to the generator or the incredible efficiency of the LED, but we’re nonetheless impressed.

Since around 2012, research into triboelectric nanogenerators has heated up, as our devices use less and less power and the structures to harvest these tiny amounts of power get more and more sophisticated. One of the coolest such electron harvesters is 3D printable, but in terms of simplicity, it’s absolutely hard to beat some pieces of metal and plastic tape shoved into your shoe.

You know how the saying goes — they don’t make them like this anymore. It’s arguably true of pretty much any electronic device given the way technology changes over time, though whether or not it’s objectively a bad thing is going to vary from case to case.

As a practical example, take a look at the insides of this 80’s vintage HP 3314A function generator shared on the EEV Blog Forum by [D Straney].

With multiple PCBs stacked on top of each other, it’s hard to imagine that more components could possibly be crammed into it. One board in particular appears to be an entire Motorola 6800 computer, something which today would likely be replaced with a single microcontroller.

Which is actually why [D Straney] shared this with us in the first place. After seeing our recent post about a modern waveform generator that’s basically an empty box thanks to its modern components, they thought this would be a nice example of the opposite extreme.

So, is it a good or a bad thing that test equipment isn’t made this way anymore? Well, it’s hard to argue with the improved capabilities, smaller footprint, and reduced cost of most modern gear. But damn is the inside of this HP 3314A gorgeous. As one of the commenters on the page put it, hardware from this era was really a work of art.