debugging a tu58? blank tapes or bad read channel?

On Wed, 31 Mar 2004, Brad Parker wrote: Using a known non-magnetized small screwdriver (or a freshly-degaussed one), observe the head output with the scope, and move the tip of the screwdriver blade very close to the head face. If you want, you can wrap a bit of cellophane tape (1 thihkness max) around the tip to keep from scratching anything. You should see some disturbances on the scope, if you are actually watching the raw analog sigs from the head... or you may 'fool' the electronics into thinking that it's read a bit... anyway, this can give you an indication that the head is good... beware using an ohmeter on magnetic heads, unless you have a degausser for same and use it afterwards - the DC voltage from the ohmeter will magnetize the head, and this is a Very Bad Thing for subsequent tapes. Cheers John