Author Topic: Russian Diodes for dummies  (Read 449 times)

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Russian Diodes for dummies
« on: June 26, 2017, 05:18:23 PM »
Another topic about Russians.  ;D This time about diodes.
I have a collection of russian diodes, and tested them compared with 1N34A, 1N914 from China and NXP 1N4148, Fairchild 1N914. Curve tracing: DCA75.
Here is the plot:

What we can say:
1N34A seems to be real germanium (there are several topics about "fake 1n34a"). Measured them with DCA55 (in addition to DCA75): Vf from 0.3 to 0.4v.
D9B (Rus: Д9Б) is very close. Vf measured with DCA55 is about 0.4
D9E (Rus: Д9Е) often called a sub for 1N34A. Graph is close too. Vf measured with DCA55 is about 0.4-0.45
D9V (Rus: Д9В). Vf measured with DCA55 is about 0.5 (0.412-0.628)
D9J (Rus: Д9Ж). Vf measured with DCA55 from 0.4 to 0.5
D9K (Rus: Д9К) close to 1N34A. Vf measured with DCA55 is about 0.4 (0.320-0.450) mainly under 0.4v. Good substitute for 1N34a from this point of view.
Other Russian germanium types:
D310 (Rus Д310). Have more steep characteristic. DCA55 measures Vf about 0.220 (quite close measurements)
D312A (Rus Д312А) closer to 1n34a. DCA55 measured Vf about 0.3 (0.280-0.316)

There are other types of russian germanium diodes still available. I think I will make more tests, if it's interesting.

We can compare them with silicon types: NXP 1N4148 and fairchild 1N914. Very similar graphs. To the question if we can substitute one with another.  ;)
Russian si diodes KD251A (Rus: КД251А) have more steep graph. KD522B - "Russian 1n4148" (not shown in the plot) gave the same graphics as KD251A. Both were used in Big Muffs.

In conclusion: Russian germanium diodes are 100% original.  :icon_cool: Close to 1N34A, and according to many reports - usable, have their own tone.
« Last Edit: June 26, 2017, 05:30:18 PM by diy-tubes » - parts for guitar/studio gear


Re: Russian Diodes for dummies
« Reply #1 on: June 27, 2017, 09:48:00 AM »
I used the D9E's in my Aion Refractor (Klon clone), and they are simply outstanding. I tried 1N60, 1N270, and 1N34A's, and even some different germanium transistors (too leaky for anything else), but my ears kept coming back to the D9E. For lack of a better word, the clipping was just "sweeter" with the D9E's. They seemed to differentiate less between the humbucker vs. single coil question, sounding equally good with both. The real difference was at lower overdrive levels, where that "edge of break up" was very smooth. "Touch sensitivity", is that the term? Could it be that smoother curve having something to do with it? I dunno, but I like them.

Just be careful though, the line on the Russian diodes is generally the anode side, not the cathode, like we're used to. Best test before using them, unless in an opposing pair scenario where it won't matter.

Maybe do a "Japanese transistors for dummies" and "Japanese diodes for dummies" series as well. There's a plethora of details to be gleaned from those as well. For instance, nailing down all the gain letter codes (once and for all!) for the transistors. I did a write up on them, the thread is kicking around somewhere here. As for diodes, the 1S1588 is really nice for clipping. My ears appreciate them much more than the 1N4148/1N914. Maybe they have a more gentle curve too? Dunno. You're starting to give me reason to buy a DCA75... damn you! :icon_razz:
"No matter how many times I cut it.... it's STILL too short!!

Asian Icemen rise again...

Digital Larry

Re: Russian Diodes for dummies
« Reply #2 on: June 27, 2017, 11:29:54 AM »
I'd expect that D9V to sound quite a bit different than anything else there.  Got any sound clips?
Digital Larry
Holy City Audio - home of SpinCAD Designer


Re: Russian Diodes for dummies
« Reply #3 on: June 27, 2017, 02:38:21 PM »
I've seen verbal description only. This guy say they sound similar to D9E.
Quote from the link:
1. Very similar to the D9E tonally, but the breakup happens a lot sooner.
2. Unlike the D9E, these will break up when you play hard, and they are much edgier. - parts for guitar/studio gear


Re: Russian Diodes for dummies
« Reply #4 on: July 16, 2017, 03:48:02 PM »
Another picture. Added D2D, D18, D311. I will offer diodes kit if it's interesting, so everyone can test them. - parts for guitar/studio gear


Re: Russian Diodes for dummies
« Reply #5 on: September 19, 2017, 03:19:26 PM »
More diodes tests.
1N60 reissue (China), 1N270 reissue (China), 1N270 NOS (two black lines, housing similar to Russian GE diodes) compared with 1N34A, Russian D9E, D9J and si 1N914. - parts for guitar/studio gear