[78-L] Approximating 78s age by physical characteristics

[David London]

On 04/03/13 12:50, Mark Bardenwerper wrote:
>
> There was a lead in groove, which then took the needle to be captured by
> a concentric or elliptical groove. The changers worked best with
> elliptical because the adjustment for kicking in the arm lift was less
> fussy (that was adjusted normally by setting the starting point on the
> outer rim).
>
Sorry, but I meant the lead-in groove on the outside edge of the record 
at the start of play.