Dec 06, 2004 09:58 am the ratings of the capacitors are the ones that say things like 10 uF and 1000 pF i believe...
Homemade Mics?
Posted on Dec 06, 2004 09:30 am
Disposable
Member Since: Aug 17, 2003
I just found this online and thought...
What the hell, may as well give it a try.
www.prosoundweb.com/recor...dmic_16_1.shtml
Now I have a question, it doesn't have any voltage ratings for the capacitors and stuff, and as I'm just getting into this whole electronics stuff... I need to know what voltage ratings I need of all this stuff. Do they need to match?
[ Back to Top ]
Dec 06, 2004 09:58 am the ratings of the capacitors are the ones that say things like 10 uF and 1000 pF i believe...
Dec 06, 2004 09:59 am yeah, thats it :
[quote] Circuit components:
(1) Panasonic WM-66AY Omnidirectional Microphone Cartridge (available from Digi-Key at 800-344-4539, part # P9959-ND). This capsule is a high-quality back electret type with a frequency response that is ruler flat from 20Hz to 20kHz. It contains an internal FET impedance converter making an external FET unnecessary.
(1) 1000 pF ceramic disc capacitor
(1) 10uF mylar or metalized polypropylene capacitor (DO NOT substitute an electrolytic!)
(1) 2.2Kohm 1% metal-film resistor
(1) 9-volt battery terminal w/leads
(1) 9-volt alkaline battery
Insulated copper wire
[/quote]
Dec 06, 2004 10:01 am But all the Capacitors I am finding also have a Voltage rating (i.e. 50VDC or 35VDC.)
Do these numbers particularly matter?
Dec 06, 2004 10:10 am no, just follow the directions and it should be fine. voltage is factored into ohms V=IR
The only problem is that I think radioshack only sells omni mic capsules now. Thanks for remeinding me of this though as I need some lappel mics :)
Ribbon mics are also fairly easy, the only problem is that a transformer is needed and the recommended one goes for $200 :/
Dec 06, 2004 10:13 am I probably shoudl explain... those votage ratings are for max voltage... do if it goes over 50Volts of direct current it will melt :) This is a 9volt project so no worries... if you want you can match as different raitings may have different accuracy... notice cheap components are +-20% :O
Dec 06, 2004 10:14 am Do you have a link to the ribbon mic schematic you are talking about?
Nevermind... I found one,
And boy is that transformer expensive.
I'm not too concerned about omni...
While it would be nice to do cardoid,
It's not a big deal to me.
Thanks for the tips. :)
Dec 06, 2004 10:16 am Also...
Is there any way to force an omni
To be more directional?
Is there any type of material I can use in the casing to make it more "cardoid" ?
Dec 06, 2004 10:55 am So, to make sure I understand correctly…
As long as the VDC is not less that 9 there should be no problems right?
Meaning, if I was to get the capacitors at 35VDC there would be no issues?
And in theory if I were to get them in 50 VDC and 35 VDC there shouldn't be any major issues?
Dec 06, 2004 11:20 am A lot of the ceramic disc capacitors are rated 600, 800, and 1000v so you won't have any problem.
Like Zak said, you'll have no problems running caps that are rated over your projects expected voltages. Like mentioned, you're running a 9 volt project, so there's no normal way that you'd exceed the cap's max voltage.
When you start getting into tube amps, then you can start paying closer attention to specs =)
Dec 06, 2004 11:37 am yeah...that mains voltage thing is fun... me meeting 220 volts at 30 amps has led to bits of screaming that I don't exactly remember :)
Dec 06, 2004 11:41 am ..and making an omni behave like a cardioid is no...except for parabiloc mics I think.
Dec 07, 2004 06:48 pm just for anyone interested, i just ordered some parts to make a few of these. i'll hopefully have a report in a week or so.
digikey (or actually panasonic) doesn't carry the 66 version anymore, so i ordered the 61b model instead. Its got better specs, but thinner module. Part number P11974-ND
Disposable: in making amps, ceramic caps are usually avoided for mica. I'm not sure how the mica will fit, but i'm going to try them out anyway.
Dec 08, 2004 06:40 pm ace, let us know. got as digi camera? a step by step would be ace...
Dec 08, 2004 07:45 pm This is gonna be great pjk...like flame said...it'd be good to see step by step shots.
|
Related Forum Topics: |
If you would like to participate in the forum discussions, feel free to register for your free membership.