1n34a diodes

[motterpaul]

Just FYI...

I was duped by a cheap seller of these diodes, so I just bought 50 from Tayda for about $.25 apiece. In my opinion this is worth it - based on their appearance.

The Tayda diodes I received do not look like anything you see on eBay at any price. In fact, Tayda does not show the picture because unscrupulous sellers will take the pictures and use them to sell junk.

Here is a seller on Amazon selling 1 of these same diodes for $4.53 (ship from U.S.). This one looks like the Tayda diodes. http://www.amazon.com/Germanium-Diode-Voltage-Dropping-Applications/dp/B004XNSJQM

Here is another Amazon link with a better price (same looking diodes) - but Tayda is still cheaper and they are NOS on Tayda. http://www.amazon.com/1N34A-1N34-Germanium-Diode-DO-7/dp/B00OEZDB6M/ref=pd_sim_328_5?ie=UTF8&dpID=31loPS2zUnL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=12DC88EWJPP46YHGYCQT

I suggest you click on the Amazon link to see what the real deal must look like (assuming you trust Tayda) and then go to eBay and you will see that even the expensive 1n34a's on eBay look different (and may or may not be fakes or other models).

Some of the ones on eBay look like they could be decent germanium diodes (right size, color, etc.) but I do not think they are 1n34a.

[Sensei Tim]

i bought some 1n34a's from tayda about 18 months or so ago.. never again. they all sounded like shit.

The two things that i will not buy from Tayda: JFETs and anything germanium

[motterpaul]

Well that's interesting. I have not tried these yet but I always trusted Tayda to have good parts.  I wonder if you and I got the same ones, did you happen to look at the pictures in the links?

[Sensei Tim]

Yeah. the ones i got from tayda were not like the ones in the amazon link.  The bands look different.  If i remember sometimes tayda and other sellers sell "functionally equivalent" diodes.... on paper they have the same performance specs, but they are not germanium diodes.

I bought a huge lot of D9E diodes from russia right after the "new" klon updated schematic came out that recommended the D9E diodes and i've been using those for everything since and i've been more than happy with them.

[motterpaul]

Does anyone here have a picture of a "real" 1n34a Ge diode?

If you go to eBay you see probably 10 different diodes. The ones I have show distinctive double black bands, some clear glass showing, and are about twice the size of an 1n914.

[induction]

Remember, a component is defined by a datasheet. If its measured specs match the tolerances of the datasheet, it's 'real'. If it doesn't, it's not. Lots of semiconductors can't be manufactured to precise specs, so they make a ton of them, then label them according to how they measure. It's generally not possible to tell these specs by looking at them, and there's no reason to expect different manufacturers to use the same cosmetics (band colors, etc.)

If you want to know whether a diode is Ge or Si, there's no sure-fire way to tell from looking at a picture, but if it's a small package (1N4148 size) it's probably Si. If it's a larger glass diode with a visible cat whisker, it's probably Ge. Whether it's a 1N34A depends on the measurements.

In most applications the difference between Ge and Si is only about the forward voltage, and the knee. (I'm pretty skeptical the latter, to be honest.) If you replaced a Ge diode with a Si diode that has exactly the same Vf, could you hear the difference? I never have, but maybe that's just me.

[motterpaul]

Good answer, Indy. I did see one eBay seller actually post a data sheet on some Ge Diodes.

[Beaker]

       
"Does anyone here have a picture of a "real" 1n34a Ge diode?

If you go to eBay you see probably 10 different diodes. The ones I have show distinctive double black bands, some clear glass showing, and are about twice the size of an 1n914."

You would probably need 10 ten photos to show all the different "real" ones.

As Induction said, the small ones are almost certainly Si Schotky work-alikes, while the larger ones should be Ge. Be aware though that they can have one wide black band, two narrow black bands, or even one wide green band. There may be other variants too.

There are other diodes too that have one or two black bands - old 1N60P spring to mind, so effectively look identical to the 1N34A you are describing.



This guy is having the same issue:

http://www.petervis.com/Radios/making-a-crystal-radio/crystal-radio-diode.html

We have just found out that Russian D9 diodes also come in silver cases as well as the more common clear glass - something I don't think anyone here had come across before. See the "mystery parts" thread further down the page.

What I'm trying to say is that I don't think anyone can say "these are the real deal" or "these are wrong-uns" just by looking at a photo on a website, or an ebay or amazon listing.

And whether you even get the same thing as in the photo is another matter altogether...

[motterpaul]

Here is what I got ....

Testing 1n34a:

Diode junction
Red-A Blue-K
Vf=0.610V at 5.00mA

§ Diode Junction is displayed for diodes or diode junctions (pn junctions).
§ Forward voltage measured at a nominal test current of 5.0mA ±0.25mA.
§ Voltage accuracy is typically ±1% ±0.006V.
§ Valid forward voltage range is 0.15V-1.49V.
§ Infra-red LEDs may fall within this voltage range.



Testing 1n270:

Diode junction
Red-K Blue-A
Vf=0.530V at 5.00mA

§ Diode Junction is displayed for diodes or diode junctions (pn junctions).
§ Forward voltage measured at a nominal test current of 5.0mA ±0.25mA.
§ Voltage accuracy is typically ±1% ±0.006V.
§ Valid forward voltage range is 0.15V-1.49V.
§ Infra-red LEDs may fall within this voltage range.

[Travis]

Sensei Tim wrote

i bought some 1n34a's from tayda about 18 months or so ago.. never again. they all sounded like shit.

The two things that i will not buy from Tayda: JFETs and anything germanium

There's quite a lot of stuff that I won't buy from Tayda, but I have gotten their 1N34A (the larger germanium ones) and they have tested and sound as I would expect from 1N34A. My only complaint with them is that they break very easily. I have broken tons of them while simply bending the legs

[Beaker]

"My only complaint with them is that they break very easily. I have broken tons of them while simply bending the legs"

Then buy yourself some cheap round nosed jewellers pliers. Grip the lead just past the glass and bend the lead round the curve of the jaw. You will never break another diode again.

Something like these:

http://www.ebay.co.uk/itm/Beadsmith-Economy-Round-Nose-Beading-and-Jewellery-Making-Pliers-E36/331566994135?_trksid=p2045573.c100508.m3226&_trkparms=aid%3D555014%26algo%3DPL.DEFAULT%26ao%3D1%26asc%3D20151016114742%26meid%3D95491e0d6f84465291f1b66e2d6b6572%26pid%3D100508%26rk%3D1%26rkt%3D1%26

[motterpaul]

I break them when I have to replace them for any reason - I guess the glass heats up when you desolder.

[Gentle_Jack_Jones]

FWIW, I put a Tayda 1N34a in a circuit last week. It was glass and looked like a Ge diode, and the forward voltage was about .250 v. It was put in an Orange Squeezer, and I don't know how much (if at all) it contributes to the sound of the effect, but the effect sounds good.

But at least the Tayda diode looked like a 1N34a and forward voltaged like a 1N34a.

[motterpaul]

Funny - my "cheap" 1n34a diodes rend to fall in .250V range - they're tiny ones, like 1n914s.

On 5/26/2016 12:21 PM, Gentle_Jack_Jones [via Guitar FX Layouts] wrote:

FWIW, I put a Tayda 1N34a in a circuit last week. It was glass and looked like a Ge diode, and the forward voltage was about .250 v. It was put in an Orange Squeezer, and I don't know how much (if at all) it contributes to the sound of the effect, but the effect sounds good.

But at least the Tayda diode looked like a 1N34a and forward voltaged like a 1N34a.

---

If you reply to this email, your message will be added to the discussion below:

http://guitar-fx-layouts.42897.x6.nabble.com/1n34a-diodes-tp30980p31016.html

To unsubscribe from 1n34a diodes, click here.
NAML

[Beaker]

"Funny - my "cheap" 1n34a diodes rend to fall in .250V range - they're tiny ones, like 1n914s."

Not suprising at all. As Sensei Tim pointed out in his second post, the little Schotkky versions are"functionally the same as" the bigger Ge ones, even if they are Si. They have performance characteristics that mean they will perform exactly the same in probably 95% of cases.

Unfortunately us pedal builders and vintage radio boffins are the other 5%, and we are the only awkward bastards who get our knickers in a twist about this. (Have you noticed if you google an old Germanium diode, and filter out all the datasheets and ebay listings, the only hits you end up with are to do with pedals or crystal radios?).

Even in a pedal, they should function exactly the same. They may not sound the same, but I think that depends on the circuit - in some circuits you may not be able to hear any difference, in other circuits you might hear a difference. And that's where the problems start...

IMHO just buy a load of D9, D18 and D310/11/12 diodes from Great Uncle Bulgaria or any of the other Eastern European sellers, and you will never have to worry about possibly fake 1N34a again.

Anyway, this makes an interesting read:

http://rezzonics.blogspot.co.uk/2014/01/germanium-diodes-vs-schottky-diodes-for.html

[heuermh]

Beaker wrote

"Does anyone here have a picture of a "real" 1n34a Ge diode?

You would probably need 10 ten photos to show all the different "real" ones.

On that note, here are a few old timers in different forms:

[Travis]

^^ very cool! Look how thick those leads are!

I got some interesting old RCA diodes which look like a Ge transistor but they are Si diodes. Can't always judge a book by it's cover

[Gentle_Jack_Jones]

Where do you presumptive good 1N34a's from Tayda fall Paul?

One way or the other, I'm thinking I should place an order in Bulgaria!

[Gentle_Jack_Jones]

Beaker, which Bulgarian diodes substitute for which common Western Ge diodes?

[motterpaul]

If you are asking about specs of the 1n34a from Tayda I posted those in a post up above this one (the post with the picture)