So long 2N5089, J310 ... and 2N3904!?

[midwayfair]

From RobA over on Madbean:

Got an email alert from Mouser this morning about On Semi moving the J310 and 2n5089 PTH transistors to end-of-life. I checked a few others, including the 2n3904 from On Semi and they are listed as EoL too. Things must be getting serious if they are killing off the 2n3904.

Darn it.

[sajy_ho]

I never used 2N5088-89 in my builds and always replaced them with BC550C, but 2N3904?! I don't know what to do without it; It's almost in all of my builds... 

[Kipper4]

Thats It !
Time to cry myself to sleep.

[R.G.]

They're stopping production of the TO-92, in general I suspect.

Our little sandbox is fun, but it exists on the leavings of the actual, real electronics industry. There are almost no new designs for through-hole transistors happening, so the manufacturers, urged by the whisperings of their captive MBAs to read the future and not the be last company to hold unsold inventory of parts that no one (in the REAL electronics industry) wants.

Get used to it. 

[smallbearelec]

There will be no shortage of TO-92 for DIY for some time yet, as we are pretty well-stocked with popular numbers. What scares me is the eventual phasing out of DIP in favor of SOIC. I'll get a Taiwanese foundry to bond SM devices to headers, if that's what it takes to keep SBE viable. However, I would like to have a few more years before biting that bullet.

SD

[amptramp]

I guess we had better go back to tubes.  No surface mount equivalent for those!

[R.G.]

I guess we had better go back to tubes.  No surface mount equivalent for those!

Ummm, well, actually, there is. Or could be, anyway.   

Check up on Field Emission Triodes.  If you want to take the trouble to pull a permanent vacuum over the top of a silicon surface, you can nan-etch pits with atomically sharp "teeth" arrays at the bottom. Put one conductive circle around the pit, and another around that. A few tens of volts between the toothed array and the outer circle boils electrons off the sharp points from sheer field strength emission overcoming the surface work function. If the tooth array is negative wrt the outer circle, electrons boil off and loop up and over to the outer-circle "plate". The inner circle grid can cut this down or off.

Sounds like a lot of work for not much benefit, right? It turns out it's massively radiation hard, which diffused junctions are not.

I first saw this in the 70s, filed it away. I just googled and the research is now all about carbon nanotube FETriodes. They're still there.

So yes, you could do an SMD tube. Just gotta etch carefully enough.

[Keppy]

Got an email alert from Mouser this morning about On Semi moving the J310 and 2n5089 PTH transistors to end-of-life. I checked a few others, including the 2n3904 from On Semi and they are listed as EoL too. Things must be getting serious if they are killing off the 2n3904.

I got the same email about 2N5551, 2N5401, & 2N6027. Maybe we should just do an SMD layout for the Phase II. It might cut it to one board. With, like, 40 jumpers.

[alanp]

Question for the experts -- I know that thru-hole tech is going the way of the thermionic valve, but how likely are discrete semiconductors likely to be EOL'ed altogether? I mean, there are SMD equivalents for BC550 and BC560, AFAIK, but are we likely to boil down to a stage where they produce SMD caps, SMD resistors, and only SMD CPU's?

Because increasingly the only thing that seems to matter in life today for people techwise is their new mobile phone... maybe I'm just being profoundly cynical.

[aron]

Wow, is this the end of our hobby? I'd hate to have to use SMD for my circuits. Even if it's 4-5 years away, it still sucks.

[Govmnt_Lacky]

I got the same email about 2N5551, 2N5401, & 2N6027. Maybe we should just do an SMD layout for the Phase II. It might cut it to one board. With, like, 40 jumpers.

    WAIT.... WHAT?   

[bancika]

So few years down the road, boutique builders will charge 400$ for pedals that have 2n3904 for that true vintage tone.

[Frank_NH]

"Wow, is this the end of our hobby?"

Very unlikely.  How many 2N3904s do you plan to use for the time you will be actively engaged in pedal building as a hobby?  If I bought 100 today, that would last me for the rest of my life.  Likewise for other similar components, including J201s.  I might be worried, however, if I were manufacturing pedals for the consumer market.

The tube example is a good one.  Who manufactures tubes for consumer electronics???  Nobody!  However, tubes are still manufactured because there is a market in the musical instrument business.  Likewise, if there is a market for anything, including 2N3904s, someone will manufacture the item to meet the demand.

By the way, the situation is far worse for guitar builders.  Many tonewoods, like certain rosewoods, ebony, and mahogany, are disappearing.  The result is that builders (including hobbyists) are now paying exorbitant prices for the woods as the supplies dwindle.  This same situation is happening now with "vintage" electronics (e.g. J201s).

I hope by the time this becomes a real problem, someone will have devised a way to make through-hole components using 3D printers!   

[Govmnt_Lacky]

Very unlikely.  How many 2N3904s do you plan to use for the time you will be actively engaged in pedal building as a hobby? 

I think you have over estimated how many people on here build pedals as "a hobby."

There are quite a lot of forumites here that are booteek builders and/or semi-professionals so I can understand the disappointment about this news.

[duck_arse]

[sob] I've never even had a 5089 to use. [/sob]

[Luke51411]

When searching for these parts on mouser it appears that there are still a few options from manufacturers that haven't been designated end of life. For the 5089 the central semiconductor option hasn't been marked end of life... same with the 3904. Though eventually they will probably all follow suit. I think maybe this is not so much a "sky is falling" moment but maybe just a reminder of the way things are going. Eventually when all production has ceased, I would think there would still be wide availability for a long time for these components just given the sheer volume that has been produced.

[rousejeremy]

So few years down the road, boutique builders will charge 400$ for pedals that have 2n3904 for that true vintage tone.

Give this man a medal.

[R.G.]

[sob] I've never even had a 5089 to use. [/sob]

There, there. It'll be all right. I have this stash of 5089's that I got directly off the test machines back at National Semiconductor. I'm aging them right now, because they sound best if they're aged for 19.34 years before ever being soldered on. They'll be ripe in about a year. I'll send you an email then. I'm pretty sure they'll be affordable fairly priced.



Seriously, just cause they're not making them any more doesn't mean we're going to be crying for TO-92s. After all, people are *still* finding caches of germanium devices, and those were discontinued back in the 70s.

I actually do a lot of SMD layout these days. The Ludwig in SMD is entirely doable. I'd probably put all the controls stuff on the top side with the pots and all the filters on the bottom side, eliminating most of the wires along the way, as the wires shrink down to through-the-board vias.

[rousejeremy]

When searching for these parts on mouser it appears that there are still a few options from manufacturers that haven't been designated end of life. For the 5089 the central semiconductor option hasn't been marked end of life... same with the 3904. Though eventually they will probably all follow suit. I think maybe this is not so much a "sky is falling" moment but maybe just a reminder of the way things are going. Eventually when all production has ceased, I would think there would still be wide availability for a long time for these components just given the sheer volume that has been produced.

I agree. There are probably billions of them out there, and there will probably be a lot more recycling in the future with old electronics gear stripped for components.

[Luke51411]

I have this stash of 5089's that I got directly off the test machines back at National Semiconductor. I'm aging them right now, because they sound best if they're aged for 19.34 years before ever being soldered on. They'll be ripe in about a year. I'll send you an email then. I'm pretty sure they'll be affordable fairly priced.

I can't wait until the day we are hearing about how the inconsistencies in the TO-92 manufacturing process is what makes them sound so much better than smaller alternatives...
Sidenote: Anyone in for a groupbuy of 2n3904 and 2n5089?