[78-L] The ultimate turntable

[Robert M. Bratcher Jr.]

At 04:48 PM 1/21/2009, you wrote:
>Robert M. Bratcher Jr. wrote:
> >
> > Astatic also made an
> > 83-d cartridge with 2 LP needles that were built into the cartridge
> > and could not be removed. This was used in the library of congress
> > talking book machine record player. When both needles wore out you
> > just put in a new cartridge.
>
>This series was known as "Power Point" because the ceramic element is
>built into the slide-in replaceable element.  The device that stays in
>the tone arm is actually just a holder.  Astatic and the other
>aftermarket manufacturers made replacements in several formats that
>included either two microgroove points or one microgroove and one
>widegroove point.  The widegroove points were probably all sapphire
>while you had choices of whether one or both of the twin microgrooves
>would be sapphire.  There might have been a special key-slot in the LC
>verson to avoid use of one with a 78 point.  There were a lot of 2-speed
>school phonos in the 70s that also used the dual microgroove versions,
>and often the suppliers for school machines had these replacement styli
>in their catalogs.
>
>Mike Biel  mbiel at mbiel.com

Interesting info.If I remember right the 2 microgroove needles in the 
cartridge used for the L-C player were diamond as they lasted quite 
awhile. There was no key slot or anything like that. When the needles 
wore out a reader just requested a new one from the state library & 
it came in an envelope. Pull the old one out & slide the new one in.