phonograph speed indicator (two)
Date: 1900-1960
Inventory Number: 2004-1-0372
Classification: Phonograph
Subject:
Maker: American
Cultural Region:
Dimensions:
each: 0.1 × 8.4 × 8.4 cm (1/16 × 3 5/16 × 3 5/16 in.)
Material:
Description:
Two cardboard disks, both with instructions for use on the underside. One disc has a plain circle in the center and black radial lines in the outer portion against a yellow-brown background. The other has black spiral lines radiating from the center against a yellow-brown background.
Signedon second disc: [...]CRAFT CORPO[...]
Inscribedon back of first disc (with truncated phrases marked by an ellipsis): INSTRUCTIONS / Place a record on the turntable in the us[...] / Place Stroboscope Disc on record (other si)[...] / Play record using grooves not covered by D[...] / If radial lines appear stationary (while Disc i[...] / [...]ng) turntable is totating at 78 revolutions per m[...] / [...]nstrument is, therefore properly regulated / If radial lines seem to be moving backw[...], turn regulating screw until they appear s[...] / Remove Stroboscope and file it away[...] / future use. / INstruments should be tested from t[...] / or five times a year). Records [...] per minute. Unless the [...]
on back of second disc: INDICATOR / Place Record on turn table. / Place this Spiral Speed Indicator on the / record, spiral side up. / Play record, using grooves not covered / by Indicator. / If black spiral lines do not appear to / stand still adjust Speed Regulator Knob / When lines appear to stand still record / is revolving a 78 revolutions per minute, / which is the speed at which records are / produced. It is very important to play re- / cords at this speed. / Note: When testing speed this indicat[...] / be lighted by a 60-cycle light.
on back of second disc: INDICATOR / Place Record on turn table. / Place this Spiral Speed Indicator on the / record, spiral side up. / Play record, using grooves not covered / by Indicator. / If black spiral lines do not appear to / stand still adjust Speed Regulator Knob / When lines appear to stand still record / is revolving a 78 revolutions per minute, / which is the speed at which records are / produced. It is very important to play re- / cords at this speed. / Note: When testing speed this indicat[...] / be lighted by a 60-cycle light.
FunctionUsed to calibrate record player speeds. When placed on top of a record and lit wih a stroboscope, the lines appar still at 78 RPM.
Curatorial RemarksThe inscriptions on the back were apparently written on a square board and then cut off when made into circles. Therefore, the full name of the constituent is not discernible.
78-RPM records were produced from 1898 to the late 1950s.
78-RPM records were produced from 1898 to the late 1950s.
ProvenancePrivate Donor, Troy, NY.