h a l f b a k e r yRIFHMAO
(Rolling in flour, halfbaking my ass off)
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Please log in.
Before you can vote, you need to register.
Please log in or create an account.
|
There are still some devices out in the world which use vacuum tubes.
Someday, there will be no source for replacement tubes. Barring the "do it yourself" approach of a French radio amateur, a more modern replacement is called for.
Imagine for a moment that there was a single solid state component
that could replace them all (with perhaps a suitable set of interchangeable bases).
The component would be programmed to replace any given tube, say a 6SN7. You would plug it into a programmer socket and configure it using a laptop, with the device characteristics being downloaded from the Internet. Then you take it out, plug it into a suitable base (which accounts for all the different possible pinouts) and plug it into the circuit.
Now, since you would only need one such device to replace any tube in existence, they could be manufactured in (relatively) large quantities which would bring the price down
BIFET vacuum tube replacement structure
http://www.patentst...atents/5648664.html
Non-programmable version [csea, Mar 19 2009]
Solid State Vacuum devices
http://www.freepate...ne.com/7397175.html
Another approach... [csea, Mar 19 2009]
[link]
|
| |
There are already a number of modelling amps for electric guitars. So I'd say this is mostly baked. |
|
| |
I'd not only plus this idea but I'd buy solid-state replacements for several different models if they were priced similarly to NOS replacement (or even slightly more). |
|
| |
But [-] because it's absurd to think you're going to emulate all vacuum tube electronics equipment with just one device or even pin bases. |
|
| |
//French radio amateur//
slang etymology ? |
|
| |
I could see this for signal-level tubes (e.g. 12AX7.)
But in no way would it be reasonable to include power FETs and heatsinks, etc. to make one device replace //any tube in existence// |
|
| |
A 5Y3GT full wave rectifier tube replacement is going to take some pretty hefty high voltage solid state devices, which are pretty useless in a signal tube. |
|
| |
Further, some tube designs put the filaments in series with panel lights, etc, as part of a voltage divider, and so the replacement would have to contain resistive power dissipating devices (i.e. heat producers) that would be unfriendly to stable solid-state devices. |
|
| |
My dad had some metal cans with tube pins that included JFETs as replacement for 12A?7 type tubes back in the mid-70s, I don't know if these were commercially available, but I think they were aimed at hobbyists updating vacuum-tube amps (back when they were considered junk compared to the fancy new transistorized amps - I witnessed some MacIntosh 275s (classic tube amps with great transformers) being disposed of back then, alas! |
|
| |
As a man with a few valve amps [+] (Some even home made, good way to learn about electrocution). Don't forget to program in the slow warm up, some nice analogue hum, and a loss of soundstage cohesion with age. |
|
| |
I'm not so sure this makes much sense. Apart from the technical difficulties, one reason why people like valves is for their enhanced (sound) "warmth" etc. |
|
| |
A Tchube-on-a-Tchip might be interesting though. It should be possible to build little evacuated cameras into a convential chip and a sufficient voltage drop for a couple of millimetres. Not so sure about a source of free electrons... And I guess you'ld have fewer, so it might be quite noisy. |
|
| |
//a French radio amateur//
Un jambon radio? |
|
| |
I suspect that you could have a pin out harness with a "bulb on it that replicated the tube glow (specific cheap bases for individual tube designs, or just jumper the pins) and a harness that trailed off to your SS "tube simulator" wich could be of a universal design. The tube concept is pretty uniform and I could easily see a simple discrete board that served to replace all the tubes in a device. My Bekman DU spectrophotometer has a lamp power supply with tubes that have to be replaced on a regular basis (one in particular carries more current than it really should and I suspect that peak heating is the issue). The heat rolling off this power supply is adequate to keep my feet warm in the winter so a cheap efficient upgrade might pay for itself with lots of use even if the tubes are still available (salvage!). |
|
| |
Another objection is that vacuum tubes don't break as easily as silicon if there is a power spike. Many devices probably use tubes for that reason. |
|
| |
//vacuum tubes don't break as easily as silicon if there is a power spike//
OTOH, the silicon ones will survive more power cycles than the filamented ones.
I've also got a feeling that vacuum valves survive EMP better than silicon, so post-apocalypse we'll still be able to enjoy live music. |
|
| |
Absinthe, quite that's why the Russian MIG used to valves in their aviaonics (or so they would have you belive). |
|
| |