As we’ve said many times here on Hackaday, it’s not our place to question why people make the things they make. There’s a legitimate need or utility for many of the projects we cover, no doubt about it. But there’s also a large number of them which are so convoluted that they border on absurd. Not that we love the crazy ones any less, in fact, we usually like those the best.
So when we saw this incredible modification to a Panasonic RN-404 microcassette recorder which replaces the audio hardware with a custom built vacuum tube amplifier, we didn’t bother asking what the point was. Perhaps it’s an attempt to make the most impractical method for recording and playing back audio, or maybe it was just to see if it was possible. No matter why it was done, it’s here now and it’s absolutely glorious.
If the look of the hardware didn’t tip you off that this project makes use of old Soviet-era components, the video after the break certainly will. Specifically, it’s using 1ZH25R and 1S38A tubes which were originally intended for military use. Just like all cool old Soviet tech was. Say what you will about the Cold War, it certainly got the engineering juices flowing.
There’s quite a bit of information about how these ancient tubes were brought back to life by way of this gorgeous home-etched PCB. Suffice to say, working with tubes is an art to begin with, but working with such small and unique ones is on a whole new level.
This isn’t the first time we’ve seen some tiny tubes make their way into a piece of consumer audio equipment, but this one certainly takes the top spot in terms of professional final results.
makes it nuclear attack resistant ;-)
What about the 45V DC-DC step-up module?
What about the magnetic tape it’s supposed to play?
Tubes might make a comeback (NVCT).
https://en.wikipedia.org/wiki/Nanoscale_vacuum-channel_transistor
That’s quite impressive work! I’ll need that integrated into a PipBoy before 2077.
Sweet!
Well done! That’s no small achievement, it took lots of hours to do.
hats off, especially for the home made pcb.
I love the tubes mixed in with SMT components (It would of been funny to see tubes designed for “pick & place”)
Look up the Nutube series, DIP packages with tech based on VFDs. They work well and are “tubey” enough in their characteristics that the guitar guys are pretty happy with them.
Thanks! Found some info:
https://korgnutube.com/en/guide/
http://www.nutube.us/
They are available for $49 each.
Vacuum tubes and SMD passives.
That’s like wearing medieval chain armor but fighting with a laser sword. :-)
where to get laser sword?
Looks like a plausible technology mix I have seen before:
http://www.oilempire.us/oil-jpg/brazil-lime-computer.jpg
In the future, fiction will lump technological generations of today’s present and recent past into one, anyway, like it does today with past centuries
https://imgs.xkcd.com/comics/period_speech.png
*hipsterism intesifies.
Jk, really nice job!
Very nicely done!
For bonus points, use a tiny electromechanical relay to function as a vibrator circuit to replace the solid state DC-DC converter employed for the 45V rail… :-)
Guess how long that relay lasts, and how much nasty EMI it generates.
Guess how they were doing it before solid state ever became a thing.
Not with standard relays, they have an endurance of 500k to 2M cycles.
They used special high endurance contacts. Car alternators had an external regulator box, that also had a switching contact for the excitation winding.
I had a (damaged) tube car radio when I was a child, but back then I didn’t know enough to repair it, so I took it apart.
It had a self-oscillating interrupter in an aluminum tube, that powered the primary winding of the anode voltage transformer.
Of course. I was merely channeling my inner hacker :-)
“It had a self-oscillating interrupter in an aluminum tube, that powered the primary winding of the anode voltage transformer.”
A.K.A. “chopper”
A.K.A. Vibrator
Sometimes you’d find them with an extra set of contacts that were used as a synchronous HT rectifier.
The switching contact of the alternator regulator did not arc very much. It had a bypass resistor
…and before EMI was a thing :-)
Look up chopper amplifier.
Ferengi Rule of Acquisition # 34: War is good for business.
Ferengi Rule of Acquisition # 35: Peace is good for business.
I guess its all good for business, unless you are a socialist. Then you just complain about the cis-gendered white patriarchy while drinking a $4 coffee at Starbucks.
Guess that means… Rule 34 of the ferengi internet… There is profit to to be made from it. No exceptions.
Meh. I don’t get all the hate on Starbucks.
Sure, their coffee is just over-priced, over-cooked goo that tastes more like something one might use to test red litmus paper than something one would want to injest.
But.. it’s everywhere and it usually has about the highest caffeine content in town. Admit it, that’s what you drink it for anyway so they just know their market.
Huh? Since when is the US looking to start a new war? A war never started when Obama bombed Syria for exactly the same reasons.
Besides, everybody knows that Trump is Putin’s puppet, so Trump must have received Putin’s permission before bombing Syria.
… well THAT went off topic! ;)
Next up….
Vacuum tube vcr!
Philips already did that
Four Soviet tubes designed for use in radar-homing missiles and one Western one.
He also built a vacuum-tube stereo cassette player around an old Latvian Walkman clone.
We are glass tubeway days now seem so unreal