roger, Not sure what you mean by a "negative positive talking light tester"
Are you wanting to test circuits for continuity or voltage, or to test light bulbs or what? There are continuity and voltage testers that use tones which is often better than speech cause it's faster. There is a talking "DMM" digital multi-meter if you need more exact measurements of voltage, current resistance and so on. Please be more specific so we can help. Tom Fowle Rehab Engineer Smith-Kettlewell RERC