Data logger design

[Philip Frampton]

Hello,

I'm looking for a data logger with and ADC capable of >300khz. The aim
is to record from an ultrasonic microphone (bat detecting) to a palmtop
or laptop.

The requirements are :

USB
12-bit preferably

300khz (bats squeak up to 120khz)

battery or PC powered (over USB)

There are several solutions in the form of commercial scopes and
software, but a homebuild schematic would be great as most of the fancy
features of a fast scope aren't needed and cheap ADC don't sample
frequently enough.

If someone could point me in the right direction. I'm sure I saw a 8mhz
ADC in one of the electronic magazines a while ago but I can't find it
now. If someone has some hints I can call up a magazine from the library
archive.

Many thanks,
Philip

 

[Rob]

Hello,

I'm looking for a data logger with and ADC capable of >300khz. The aim
is to record from an ultrasonic microphone (bat detecting) to a palmtop
or laptop.

The requirements are :

USB
12-bit preferably
battery or PC powered (over USB)

There are several solutions in the form of commercial scopes and
software, but a homebuild schematic would be great as most of the fancy
features of a fast scope aren't needed and cheap ADC don't sample
frequently enough.

If someone could point me in the right direction. I'm sure I saw a 8mhz
ADC in one of the electronic magazines a while ago but I can't find it
now. If someone has some hints I can call up a magazine from the library
archive.

Many thanks,
Philip

Philip, I'm not sure if you want to record the bat's actual "chirp" - it
sounds like you may want to, but there are a number of bat detector circuits
around. I can't remember where I saw them, it may have been on Dave
Johnstons Imagineering site. Googling should point you to something. These
were for detecting bat "events" rather than details of the bats actual
sounds. You may be way past this so this may not help you at all. Have fun.
rob