In a message dated 7/28/2008 1:52:11 P.M. Eastern Daylight Time, hessel@soundscape.nl writes:
With the machine on?
Please do it with the machine off. Wiggling wires is not usually a good idea when it is hot. The other way to check is with an ohm meter. Unplug the head block and connect one lead to the connector center pin and the other end on the center wire where it is soldered to the tape heads. You should get a null reading. Wiggle the wire and check again. Same thing with the sleeve. If you get anything else, your connection is bad.