Take a VERY thin piece of veneer timber! Thin it down some more by sanding, place it over a picture frame and fix it there, then do the same thing with a needle in the centre of the timber pointing vertically, balance your carbon rod so that it JUST touches the needle. Run a low power source from the needle to the Amplifier and the carbon rod to complete the circuit. Turn up the gain and when a centipede walks on the board you will hear A GALLOP, YOU WILL BE TRULY AMAZED!! Cheers Mike
Great video. I am always looking for new projects, and it seems the old books (and by extension, the old hands) have the best material. Thank you for taking the time to record and upload.
Cool video! The reason why I was searching for a Carbon Microphone was because the first book I ever rented in my life (1992, when I was 7 years old) was about electronics. The first project was a carbon microphone. Unluckily I could not find mineral carbon anywhere! Now I'm 37. During the pandemic, my interest for electronics restarted and I got hooked on it. I think I will close that circle to complete the circuit and give it a shot. Thanks for your content!
Another great video; thanks! There is a lot of DIY chatter regarding using Piezo wafers as triggers for electronic drum sets. I wonder if your carbon microphone (particularly the cartridges) might be better for the purpose. It might make for an interesting comparison video, if quantified with oscilloscope readings, etc. On another point, you used a third graphite rod to span the two sensing rods. Does this connection need to be graphite, or would copper wire work? Also, the third rod is not secured to the sensing rods. That made me wonder about the effects of vibration causing minute disconnections. Hmm, another thought... Could it be that only one graphite rod is all that is really needed?
Hello- I am interested in rebuilding a non-working carbon microphone element. Two questions: 1) Which activated carbon is more effective, small granules or finely ground carbon dust? 2) Is voltage from a computer USB port adequate? (About 5 VDC)
Old carbon mics usually fail when the carbon clumps up (called "caking"). You can try shaking it or tap it on a table top. The replacement granules should be around 1mm (looks like sand) to minimize caking. You could also add a bit of dry lubricant like silica powder. It should be operational with 5 volts.
@@0033mer Thank you for your prompt reply. When I took apart the carbon element, the carbon was very actually much finer than sand, more like dust. So just wanted to know if there was a difference to how the carbon reacted when energized, aside from the potential "clumping" issue.
Take a VERY thin piece of veneer timber! Thin it down some more by sanding, place it over a picture frame and fix it there, then do the same thing with a needle in the centre of the timber pointing vertically, balance your carbon rod so that it JUST touches the needle. Run a low power source from the needle to the Amplifier and the carbon rod to complete the circuit. Turn up the gain and when a centipede walks on the board you will hear A GALLOP, YOU WILL BE TRULY AMAZED!!
Cheers
Mike
Great video. I am always looking for new projects, and it seems the old books (and by extension, the old hands) have the best material. Thank you for taking the time to record and upload.
You're welcome.
Cool video! The reason why I was searching for a Carbon Microphone was because the first book I ever rented in my life (1992, when I was 7 years old) was about electronics. The first project was a carbon microphone. Unluckily I could not find mineral carbon anywhere! Now I'm 37. During the pandemic, my interest for electronics restarted and I got hooked on it. I think I will close that circle to complete the circuit and give it a shot. Thanks for your content!
You're welcome. Thanks for the visit.
Most informative channel, you are providing useful information and knowledge , thanks for sharing it with us!
Greetings from Greece!
Vasilis K
Hello Vasilis. Thanks for the feedback.
Greetings from Canada.
Another great video; thanks! There is a lot of DIY chatter regarding using Piezo wafers as triggers for electronic drum sets. I wonder if your carbon microphone (particularly the cartridges) might be better for the purpose. It might make for an interesting comparison video, if quantified with oscilloscope readings, etc. On another point, you used a third graphite rod to span the two sensing rods. Does this connection need to be graphite, or would copper wire work? Also, the third rod is not secured to the sensing rods. That made me wonder about the effects of vibration causing minute disconnections. Hmm, another thought... Could it be that only one graphite rod is all that is really needed?
Great video, genuine guy
Nice, it really helped, thanks man
thank you for this video.
You're welcome!
Can you show the schematic of the second set up?
This was not helpful to me but I think you're still doing a great job
Curious why you refer to the transformers with values in Ohms. Shouldn't they be rated in Henry?
6:36... I'm sure you meant to say "a pencil graphite Lead"...;)
I was wondering how long it would take before someone noticed that.
It was late .... but you know what I meant :O)
Is there a way to use it as a mic for a computer or phone?
Were are examples of sound of your microphone (when the one was in action)?
3:40
Hello-
I am interested in rebuilding a non-working carbon microphone element. Two questions:
1) Which activated carbon is more effective, small granules or finely ground carbon dust?
2) Is voltage from a computer USB port adequate? (About 5 VDC)
Old carbon mics usually fail when the carbon clumps up (called "caking"). You can try shaking it or tap it on a table top. The replacement granules should be around 1mm (looks like sand) to minimize caking. You could also add a bit of dry lubricant like silica powder. It should be operational with 5 volts.
@@0033mer Thank you for your prompt reply. When I took apart the carbon element, the carbon was very actually much finer than sand, more like dust. So just wanted to know if there was a difference to how the carbon reacted when energized, aside from the potential "clumping" issue.
The design of your mic probably needs fine carbon so use that as the replacement.