1n34A

[Marbles]

Hi again.. ;)

A friend wants me to build a fOXX tone machine. It needs 1n34a diodes. Since Banzai and Musikding are out of them for now, I was looking for other ways. I found a guy who sells them, and these are the specs.. Would they work in the circuit? I have seen so many ratings that I'm confused what's needed.

[induction]

The value you're interested in is the forward voltage (usually denoted by Vf), which isn't listed in the specs above. It refers to the amount of voltage that will be dropped across the diode when it conducts. 1N34a usually have Vf somewhere around 0.3 V or so, though the datasheets I've found sometimes only give a maximum value of 1.0 V. They will vary a little bit from device to device, but you can measure Vf with a DMM.

Probably any diode with a similar Vf will work fine. This includes most germaniums (1N60, 1N270, etc.) and schottkys (eg. 1n5817, BAT 46, etc.). Lots of people buy a handful of different types and then swap them on the breadboard until they find the ones they like best.

[Marbles]

Thank you for your clear explanation!

Do you happen to know what the forward voltage I would need is?
Thanks for your substitutes too! I will try that too. Though the person i'm building it for probably wants to hear that is is exactly the same haha

[induction]

Marbles wrote

Do you happen to know what the forward voltage I would need is?

Probably something near 0.3 V. Most Ge's will get you there. Most Si's are closer to 0.7 V. And led's just go up from there: 1.0V - 3.0V depending on color/part number.

[rocket88]

On eBay there are some Schotkey diodes sold as 1n34a's that have the correct forward voltage. They're are green with a copper band. They sound freaking fantastic, IMHO, but you got to make sure they are not listing them as Ge 1n34a's or you will over pay. If you need and are in the US I can send you a pair for the job if you can't find them yourself.

[Marbles]

Thanks a lot for both of your replies!

Not located in the USA unfortunately, but thanks for the offer! That's very nice.
I'm located in the Netherlands. Did look on ebay, but could almost only find 'very good deals' from China. Have heard some 'not that good' stories, so was kind of afraid to order them there.

Saw these.. cheaper than banzai. No fancy greent though... would they be any good?

http://www.ebay.nl/itm/271854145862?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

[Beaker]

Found these in Canada - 25 for ten Euros - seems a reasonable deal.

http://www.ebay.co.uk/itm/New-GREEN-1N34A-Germanium-Diodes-Crystal-Tube-Radio-25pcs-LOOSE-/221768565088?pt=LH_DefaultDomain_2&hash=item33a26fc160

Zach, what is the difference between the green band and the black band versions?

[Marbles]

Thanks! Didn't see that one :)

Ordered it, including shipping costs, 10 euros is indeed a fine price.