1n4148 - any difference between new and old?

[cajone5]

I got a vintage style PCB for a Grey DOD 250 and all vintage correct parts are on there already except the diodes.  I have some Tayda 1n4148's here and can slap them in but was curious if there is any difference between current production 1n4148's and those available in the 70's.  Anyone know?  If there's some mojo to be had there, anyone have a couple 1n4148's they'd like to part with for a reasonable price?

[Govmnt_Lacky]

Didn't the 250 mimic the MXR Distortion +?

If so.. then you will want to put in 1N270 Germanium diodes in there. 1N4148s will work for sure.

I may be wrong but I thought they were almost identical circuits

[WormBoy]

Very similar circuits, but they used different diodes (ge for the MXR and si for the DOD). Current 4148s are probably the same as 'vintage' ones, but from what I have read here about Tayda, I would have some doubt about the parts you received as being 4148. In any case, measure their forward voltage. There won't be any specific mojo in 4148s, vintage or modern (although you never know with mojo), but you can add some by trying some alternative clipping setups  .

[Coda-effects]

In a more general way, I would recommend to pay attention when you order on tayda or aliexpress. From my experience, many parts are not what they are sell for, especially in the IC world (especially for vintage chips like mn3005...etc). I had the issue as well with transistors (especially germanium ones), they simply "rebrand" it to make them look like "the real deal" like oc42, nk275...etc. I guess it could be the same for diodes.

For germanium, my best sources are actually in Russia where you can find many good transistor that can perfectly fit for Fuzz Faces or other builds, and that are not overhyped...yet!

[reddesert]

I've never had a DOD 250 (built one from a schematic though), and schematics I've seen of the DOD 250 always show silicon diodes.

I don't believe there is any NOS mojo in a 1N4148; it's a pretty simple part. And I doubt Tayda is selling fake 1N4148s. Tayda doesn't sell other highly counterfeitable parts like MN300x or germanium transistors. A 1N4148 (a fairly typical small-signal silicon diode) is about the cheapest part in existence. What could you possibly substitute to counterfeit it? Wire? String? 


Edit: I will back down from this a little and admit that someone could sell fake diodes by selling parts that failed quality control. However, that would be a hard way to make money by selling failed 1-cent diodes, and none of the transistors or diodes I've got from Tayda have tested bad.

[cajone5]

This is what I figured and I will probably stick with the 1n4148's (I have a bunch) to keep its as vintage correct as possible.  Now I just need to find an old DOD enclosure and I'll really be in business...

Thanks for the advice guys!

[pickdropper]

I've never had a DOD 250 (built one from a schematic though), and schematics I've seen of the DOD 250 always show silicon diodes.

I don't believe there is any NOS mojo in a 1N4148; it's a pretty simple part. And I doubt Tayda is selling fake 1N4148s. Tayda doesn't sell other highly counterfeitable parts like MN300x or germanium transistors. A 1N4148 (a fairly typical small-signal silicon diode) is about the cheapest part in existence. What could you possibly substitute to counterfeit it? Wire? String? 


Edit: I will back down from this a little and admit that someone could sell fake diodes by selling parts that failed quality control. However, that would be a hard way to make money by selling failed 1-cent diodes, and none of the transistors or diodes I've got from Tayda have tested bad.

I suspect nobody is faking 1n4148s.  As you mentioned, they are really cheap diodes.  In fact, that's probably even unlikely for the more expensive ones.

It is possible they would get either production rejects that were released to the B grade vendors or they bought a different type of diode that was "close enough."  Since the diodes are generally not marked, most people won't catch it.

FWIW, I've had no issues with 1n4148s, but have run into issues with problematic zeners and germaniums.

[Muadzin]

You could always socket the diodes. That way if you come across some 1n4148's from a different source you can find out if there is a difference.