amplifier for the near deaf

[Unregistered]

Hi carl
can you provide an amplifier for my HH .. I am near deaf ....
Just need to boost the amplifier a little bit ..
thanks

rob

[Radioactive]

Rob

I think I answered this before. I use a vibration motor in my underwater MD. It works well and vibrates my hand as I sweep over an object. Now you can not just hook it to the speaker output. You need to build a bias circuit, that varies the voltage as a signal is detected. It increases voltage to a max of three volts at full buzz. You can not tell the frequency (like the high pitch one you get when you move over, say, gold). I think a second circuit could be added to tell the freq. It could turn on and off at a different rate for different objects. I'm thinking of working on that. I also added a few leds to give a visual effect of the MD. I have great hearing but underwater headphones are to expensive for me, hence the vibrating motor.

I got mine at ALL Electronics and look under MOTORS.

This is the one I got:


Low voltage, low current miniature vibrating motor. Operates on 1.5 - 3 Vdc @ 62 mA. Tiny motor with offset weighted shaft is used in cell phones and pagers for vibrating alert signal. A removable black rubber boot surrounds the motor and provides a flat mounting surface. Without the rubber boot the motor measures 0.24" dia. x 0.5" long. The shaft and weight add an extra 0.21" to the overall length. Prepped with 0.42" long metal tabs.
CAT# DCM-204

Your Price: $1.25 each

Nice price, but you need to be very good with your iron and with SMT devices.

Good Luck Rob

[Elie]

You can get a motor from a discarded device.

[Radioactive]

That is true, look around for an old pager. That is what the motor I stated above came out of (new stock). Make sure it's a pager that uses one AA battery (1.5 VDC), that way you will have a 3 volt motor.

Good Luck

[bugwhiskers]

Crystal earpiece

Try a crystal earpiece sold by many electronics stores. They are very loud and consume very little power as they are designed to be used in a cystal set that has no power supply at all !