Newbie

[kingtravel]

Hi all, I'm new here. I need some help.

I got a guitar from a friend of mine (unknown brand but good body wood). I paid it about $20 third hand 

When I raise the volume up on my amp she starts making feedback. What could the problem be?

Thanks.

[curtisa]

Most likely the pickups are microphonic - the copper windings and/or other mechanical components of the pickups are loose enough to permit acoustic feedback to develop between guitar and amp, which manifests as high-pitched squealing.

The usual fix is to wax-pot the pickups, whereby the pickup is immersed in a vat of liquified parafin wax and then subjected to a vacuum as the wax is cooled. Unless the pickups are particularly special, you're probably better off just replacing them with better quality units, rather than performing the wax potting. The cost of DIY wax-potting one set of pickups would probably outweigh the cost of some new Tonerider, GFS or Irongear budget pickups.