super sensitive microphone

[|-|erc]

Any ideas how to record faint background noises? All the mikes I tested you have to speak into.

Herc

 

[JERD]

Any ideas how to record faint background noises? All the mikes I tested
you have to speak into.

Herc

We sure need more information on this question!

JERD

 

[David L. Jones]

Any ideas how to record faint background noises? All the mikes I
tested you have to speak into.
Herc

Most regular omnidirectional electret mic elements are very sensitive.
http://jaycar.com.au/productView.asp?ID=AM4010
Used in their zillions in standard PC desk mics and headsets etc.
Gain'em up as required.

Dave.

 

[|-|erc]

We sure need more information on this question!

A satellite(s) follows me everywhere making noise (voices) probably by heating the air
at accoustic frequencies with a MASER.

For 7 years straight, verbally abusing me all day every day, and no its not in my head.

Herc aka The Truman

 

[|-|erc]

Most regular omnidirectional electret mic elements are very sensitive.
http://jaycar.com.au/productView.asp?ID=AM4010
Used in their zillions in standard PC desk mics and headsets etc.
Gain'em up as required.

I had a FM bug that was more sensitive than the human ear, when someone was pouring
a cup of tea I could hear it swirling and the pitch increasing. But the FM bug I just got
from Talking Electronics was not very sensitive.

Can you buy something like a birdwatchers sound recorder?

Herc

 

[David L. Jones]

I had a FM bug that was more sensitive than the human ear, when
someone was pouring a cup of tea I could hear it swirling and the pitch
increasing. But
the FM bug I just got from Talking Electronics was not very sensitive.

All of the Talking Electronics bugs I built as a kid all had a standard
electret microphone and could pickup anything "better than the ear" as
you've found before.
The new one you have obviously doesn't have enough gain, and/or has an
insensitive mic. Perhaps it's designed for a different application?
Can you change the gain on the front end amp?
I'm sure Colin Mitchell at TE will be able to tell you what you need to
know.

Dave.

 

[|-|erc]

All of the Talking Electronics bugs I built as a kid all had a standard
electret microphone and could pickup anything "better than the ear" as
you've found before.
The new one you have obviously doesn't have enough gain, and/or has an
insensitive mic. Perhaps it's designed for a different application?
Can you change the gain on the front end amp?
I'm sure Colin Mitchell at TE will be able to tell you what you need to
know.

OK maybe its my radios. I tested it on a radio with a broken antenna and a
MP3 player with a digital tuner, which went up in increments of 0.05 MHZ
so it might have been out a bit. I'll get another radio to make sure it's not the
bugs fault.

Herc

 

[Trevor Wilson]

Any ideas how to record faint background noises? All the mikes I tested
you have to speak into.

**Depends on what you are attempting to do. Usually, a good directional mic
will provide what you want. There are a couple of variants on directional
mics. You can construct something yourself, using a mixing bowl, with the
microphone mounted at the centre. Similar to a satellite dish.

 

[Rheilly Phoull]

**Depends on what you are attempting to do. Usually, a good directional
mic will provide what you want. There are a couple of variants on
directional mics. You can construct something yourself, using a mixing
bowl, with the microphone mounted at the centre. Similar to a satellite
dish.

Maybe there's a maser beam converter program somewhere that will convert the
beam into audio.

Rheilly P

 

[Trevor Wilson]

Maybe there's a maser beam converter program somewhere that will convert
the beam into audio.

**Huh?

 

[Peter Parker]

I had a FM bug that was more sensitive than the human ear, when someone
was pouring
a cup of tea I could hear it swirling and the pitch increasing. But the
FM bug I just got
from Talking Electronics was not very sensitive.

Was just browsing from some old TE books yesterday

Some of the TE mics were designed more for handheld microphone use (ie not
very sensitive) whereas others were designed to be very sensitive.

A very senstive mic overloaded when spoken into at close range and hence it
needed to be throttled back.

Look for a resistor from the positive rail to the electret.

The lower the value the resistor (down to a few k ohm) the more sensitive
the mic. Conversely a higher value mic resistor (say 47k) won't be that
sensitive.

Experiment with lower values to make it more sensitive.

 

[Peter Parker]

OK maybe its my radios. I tested it on a radio with a broken antenna and
a
MP3 player with a digital tuner, which went up in increments of 0.05 MHZ
so it might have been out a bit. I'll get another radio to make sure it's
not the
bugs fault.

A tuning step of 0.05 MHz is fine for bugs (unless the bug's deviation is
really really low).

The broken antenna will restrict the range but not the recovered audio.

 

[|-|erc]

A tuning step of 0.05 MHz is fine for bugs (unless the bug's deviation is
really really low).

The broken antenna will restrict the range but not the recovered audio.

Reception was really poor on both. Too late now I ordered a $15 radio from DSE.
The frequency was 87.8 MHZ and the dial on the radio I ordered started at 88MHZ
so should be close, I pulled the coil as wide as it will go to increase the frequency.

I asked Colin to mark on the bug what frequency it was, and he put 87-92!

Herc

 

[|-|erc]

It sounds like someone talking softly in the next room. Easy to hear everything
they say, but the mike on my laptop can't pick it up.

Maybe there's a maser beam converter program somewhere that will convert the
beam into audio.

The maser beam does make audio! You can hear half a dozen American agents talking all day.
Given 1000s of people in Townsville have heard them, how would you explain a noise source
that follows you everywhere?

Herc

 

[Rheilly Phoull]

**Huh?

Did you read the post ??

 

[Trevor Wilson]

Did you read the post ??

**Yep. I saw no mention of microwaves. The reason for the dish is to
'amplifiy' SOUND waves.

 

[David L. Jones]

Lets assume for a moment there is a satellite that can punch a maser
beam powerful enough to heat surface air enough to modulate audio.

You'd spot it's presence by the burnt spot on the ground caused by the
microwave heating and by people exploding as their fluids turn to
steam.
Still it would be awesome to throw your voice at right/wrong place,
picture two teams of diplomats sitting tensely at the negotiating
table as one party awaits the reply of the other and a voice suddenly
says the wrong thing out of nowhere.

That's possible. You can buy directional speaker systems now. Woody Norris
was one of the first people to develop practical ones that worked. Here is a
demo (not that you can really hear the effect of course)

http://www.explainthatstuff.com/directional-loudspeakers.html

Dave.

 

[|-|erc]

Lets assume for a moment there is a satellite that can punch a maser
beam powerful enough to heat surface air enough to modulate audio.

You'd spot it's presence by the burnt spot on the ground caused by the
microwave heating and by people exploding as their fluids turn to steam.

Let's guesstimate the microwave to audio efficiency is 10%. The sound is
probably less than that from a 10 Watt speaker, so at the ground level you're
getting 100 Watts of microwave, the beam is probably diverged to 1m2, I
don't see people exploding from the higher energy sunlight hitting them.

Still it would be awesome to throw your voice at right/wrong place,
picture two teams of diplomats sitting tensely at the negotiating
table as one party awaits the reply of the other and a voice suddenly
says the wrong thing out of nowhere.

That's nothing, they can say and hear, and play tricks on me in public every day
and whisper in people's ears what to say about me.

In actual fact I suspect you are hearing a certain Sydney toaster/
microwave oven repairman due to cold weather atmospheric ducting of
microwaves under repair.

It's some government agency, they claim to be US. If I can just get a semi decent
microphone working I'll upload their audio.

Herc

 

[Ross Herbert]

:>
:> :>> Any ideas how to record faint background noises? All the mikes I tested
:>> you have to speak into.
:>>
:>> Herc
:>
:> We sure need more information on this question!
:
:
:A satellite(s) follows me everywhere making noise (voices) probably by heating
the air
:at accoustic frequencies with a MASER.
:
:For 7 years straight, verbally abusing me all day every day, and no its not in
my head.
:
:Herc aka The Truman


Allo..allo! I think we've got a live one 'ere....

 

[Clint Sharp]

Still it would be awesome to throw your voice at right/wrong place,
picture two teams of diplomats sitting tensely at the negotiating
table as one party awaits the reply of the other and a voice suddenly
says the wrong thing out of nowhere. http://www.cgoakley.demon.co.uk/vlhurgs/

And the entire battle fleet was accidentally swallowed by a small dog.