16" Transcription Records

Hi everyone,

I have acquired a large batch of 16" transcription records from the late 1950s, as they were going to be thrown out(!) and I seem to be the only one in my immediate city with a turntable that can handle the larger size of these records.

But I have one question about them that perhaps some older folks who worked in the radio industry or have collected them for years can answer for me: At the end of the record, just before the dead wax area leading to the label, there is a set of blank grooves that I can't seem to find a purpose for. Also, the blank grooves play for exactly two minutes when rotating at 33 1/3 rpm, so was this for some kind of broadcast calibration or equalizer check?

Thanks in advance!

They put that there to give you time to make the changeover to the next disc in a multi-disc program without a crossfader. You had time to start the next disc, turn that one up, turn this one down, and stop this one with only two hands, before it got to the locked groove at the end (which often makes a once per rotation thump). It was also a visible indicator of when the change needs to be made. With some programs (e.g. speeches), there are periods of silence that might cause the operator to make the change too soon, or let the disc play into the locked groove. This way, he can see it.

Now, almost all DJ equipment has a crossfader, so it is no longer needed.

There also may be another reason. In the days before good vinyl, they alternated center-start and outside start discs within radio programs. This prevented the sudden change in quality when changing from one disc to the next. But you played it and determined it was outside start, so that is not it.

Note that for years, transcription discs turned at 33, but had a groove needing a 2.5 mil stylus. They were also recorded with the NAB lateral transcription curve before RIAA became the standard recording curve.

Do you know if these are distributed transcriptions or aircheck transcriptions? The aircheck transcriptions were recordings made of the actual broadcasts. For years, this was required by the FCC. The aircheck discs usually have handwritten labels.

Record-changer, thanks so much for your reply! The transcription discs I have are the Standard Program Library discs from around 1957. Each record has five tracks on it, and they are just like an LP save for the larger diameter/groove width, no true lead in/out grooves, and no grooves between each track to carry the stylus over to the next one automatically. I think these were music programs that were rented by radio stations to feature up and coming artists, as opposed to an actual recording of a broadcast.