Jump to content
Electronics-Lab.com Community

Portable mic modification help


biffloman
 Share

Recommended Posts

I have a small personal sound amplifier - essentially a mic with a headphone jack - that is powered by a single AAA bat.  I use this quite a bit and wanted to mod it so that I could plug it into the AC outlet.

I soldered wire to each bat terminal and then connected the wires to a variable AC adaptor. 

When set at 1.5V I get amplification similar to while on bat power but there is a terrible whistle.  If I bump the voltage to 3v I get less whistle but less amplification as well.

Suggestions?

Link to comment
Share on other sites

I have never heard of a regulated  AC adapter with a voltage output of only 1.5V and a current output of only a few mA.

Why don't you use a rechargable Ni-MH battery cell? New AAA cells have a capacity of 900mAh which is the same as a new alkaline cell. The voltage starts lower but the average voltage is higher than an alkaline cell. They can be recharged one thousand times.

Get a spare rechargable battery cell so one is always fully charged.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
  • Create New...