Author Topic: Diode question in general, Deadringer in particular.  (Read 2836 times)

Willybomb

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Diode question in general, Deadringer in particular.
« on: August 11, 2013, 06:32:32 AM »
Got my local Jaycar to fill my BOM for a Haberdasher Deadringer.  While leaving out a 2N5088, they subbed the diodes.  I know I can sub a 1N400x for any other 1N400x, so that's not an issue, but they put a couple of 1n4148 in to replace the 1N914 and 1N43a presumably - or am I wrong?

They also included a large germamium diode with no markings on it besides the polarity band.  Which diode would that be a possible sub for in particular?

I mean, diodes are diodes really, I could probably sub most of them with LEDs if I was so inclined... but I'd like to get it as close as possible to the original BOM.

So to break it down:
Which diode(s) does the 1n4148 most closely replace?
Which diode is the the big arsed germamium, if any?

Thanks,
Willy.

kothoma

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Re: Diode question in general, Deadringer in particular.
« Reply #1 on: August 11, 2013, 06:42:58 AM »
1N4148 and 1N914 are interchangeable, as nowadays 1N914s are 1N4148s with a 1N914 label anyway.
But what's a 1N43a? 1N34A? This would be the germanium one.

Willybomb

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Re: Diode question in general, Deadringer in particular.
« Reply #2 on: August 11, 2013, 08:36:51 AM »
Yeah, it would be a 1n34a - sorry bout the typo.

RobA

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Re: Diode question in general, Deadringer in particular.
« Reply #3 on: August 11, 2013, 09:28:38 AM »
Did they give you a substitution list? You could measure the forward voltage of the Ge diode. To me, the forward voltage of the diode in with the MOSFET clippers is pretty important to the sound.
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Willybomb

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Re: Diode question in general, Deadringer in particular.
« Reply #4 on: August 12, 2013, 06:15:45 PM »
Nah, no substitution list.  I'm also replacing the 2n5088 with a PN100...

RobA

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Re: Diode question in general, Deadringer in particular.
« Reply #5 on: August 12, 2013, 10:43:44 PM »
Nah, no substitution list.  I'm also replacing the 2n5088 with a PN100...
I'd measure the Ge diode and see where the forward voltage is just to be sure that it's in the right area.

I've never used a PN100 but I'd assume it will most likely be OK because the transistors are just used as emitter followers. In other situations that could be a not so great sub.
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Willybomb

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Re: Diode question in general, Deadringer in particular.
« Reply #6 on: August 12, 2013, 10:59:57 PM »
The PN100 is just a general substitute for a stack of trannys that are a bit harder to find.  In Au, there aren't many (any) shops around - Jaycar is about it - that stock components anymore.  So, I use the PN100 when I can't be arsed waiting to get it delivered or ordered in.  I've used it as a substitute in a number of builds, the Sprout in particular and a vero project or two.

http://www.jaycar.com.au/productView.asp?ID=ZT2283

I'll look up how to read the forwarding voltage and get back to you.

RobA

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Re: Diode question in general, Deadringer in particular.
« Reply #7 on: August 13, 2013, 08:14:48 AM »
...
I'll look up how to read the forwarding voltage and get back to you.

It's easy to do. If your meter has a setting for it, you can just use it directly. If not, then just put a resistor in series with the diode and attach them from 9V to ground with the bands on the diode pointing to the ground side. A 10kΩ or something around there should be fine. Then just measure the voltage directly across the diode with your meter by putting the meter probes on either side of the diode on the leads. It's really easy on a breadboard.
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hoodoo

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Re: Diode question in general, Deadringer in particular.
« Reply #8 on: August 13, 2013, 06:16:34 PM »
In Au, there aren't many (any) shops around - Jaycar is about it - that stock components anymore. 

OT, Hey Willybomb, just thought i'd give you a heads up, i know what you mean about sourcing parts down here. First thing, Tayda is your friend ;), but if you are looking for parts locally, you need to check out RS components (the best option) or Element 14 is another way to go, all the best, Matt.