In the 1950s, radio was undergoing a programming revolution in response to television. Rather than airing most of what came down a network line (and being paid to do so), stations increasingly originated their own programming and sold their own spots to local and regional advertisers. The programming was mostly music — more and more rock and roll — featuring fast-paced format elements.
Tight playback was difficult with the standard tools of the time: turntables for music singles and transcribed spots, taped spots on small (often 3-inch) reels, live spot reads and longer-form programs on transcription discs or larger reels of tape (7 inches or more).
Gates Radio, owned by Harris Intertype Corp., sought to simplify operations by developing a control storage device using a wide audio tape belt for spots, promos and PSAs.
The ST-101 tape recorder was introduced in 1959 at the NAB Show, in an engineering session technical paper and on the exhibit floor. An article in the company’s internal Gates Studio Review noted the crowded conditions around the new “Spot Tape Recorder.” Gates reported selling 55 units at the show for $850 each (about $9,300 in 2025). By 1961, Gates claimed in a trade magazine ad that 500 stations were using the ST-101.
The 1962 Gates General Catalog described the ST-101 as storing 101 announcements, each up to 90 seconds long, on a 13-inch-wide magnetic tape. An index lever was used to select the desired cut and playback could then be started. When the 90-second cut finished, a photoelectric cell reversed the motor, rewinding the tape in 22 seconds. Individual tracks could be erased and re-recorded.
The ST-101 had a specified tape speed of 5-1/4 inches per second, a frequency response of 50 Hz–8 kHz ±2 dB, SNR of 45 dB or better, distortion below 2%, and wow & flutter below 0.35%. It used five vacuum tubes.
The unit could be mounted in a table cabinet or an equipment rack. An optional tabletop “SPOT TAPE” remote control allowed users to start playback, stop, manually rewind and control the unit.
A comment in the catalog said: “Exhaustive tests operated Spot Tape for 18,000 continuous cycles without turn-off and leaving the tape playback head on the same track, with no adverse effects on tape life or quality. Tapes may be replaced in about 15 minutes if needed, but routine exchange of tapes is not needed or recommended.”
A Gates ST-101 service manual has recently been added to the excellent World Radio History website.
Credit: Courtesy worldradiohistory.com
How reliable was it? Broadcast historian Bill Jaker shared his experience at WLIR-FM in Garden City, N.Y, on the website The Broadcast Archive.
“You couldn’t segue between spots because it was necessary to rewind the foot-wide tape — and that couldn’t be done near an open mic because the rewind sounded like a washing machine going into a spin cycle. … One morning, I came in to put the station on the air and found that the tape belt was completely wrapped around the take-up roller. Seems the guy who’d signed WLIR off the night before had shut everything down as the belt was rewinding, thus disabling the electric eye that recued the ST-101. It took some careful unwrapping and a piece of Scotch tape to get it back in order,” Jaker wrote.
“I once asked the station owner what we’d do if we had more commercials than would fit on the limited tracks of the belt tape. He smiled and said, ‘Then we’d have enough money to buy a second ST-101.’”
Even without the benefit of hindsight, the ST-101 presented several operational limitations that were immediately apparent.
Spots had to be recorded or dubbed in the control room while it was on the air. A spot couldn’t be saved while another was playing. Two announcements couldn’t play back-to-back. Further, a device malfunction could render all announcements unplayable. And there seemed to be no notion of a backup tape, meaning a damaged one could put the station’s entire spot inventory at risk.
Radio history enthusiast John Schneider acquired two derelict units and used them to restore one working machine, which is currently on loan to the GatesAir factory museum.
“Its idiosyncrasies made for interesting situations at times,” Schneider said. “For instance it was customary to play a recorded spot, read a live spot and then play another recorded spot. The whir-clunk rewind of the machine was always heard in the background during the live spot, and the head position had to be changed out of the corner of one’s eye while reading the spot.”
By 1963, the ST-101 was no longer listed in Gates’ general catalog.
Interestingly, Gates was already offering a cart deck at the same time as the ST-101 called the Cartritape. The 1962 catalog specifically noted that “Spot Tape” was not an automation system. However, as electro-mechanical automation systems became more popular, Gates needed a multiple cart player for them. Automated Tape Control (ATC) in Bloomington, Ill., had one in its Model 55, along with a large installed base of single-cart decks. Since Harris-Gates couldn’t beat them, they decided to buy them.
In an ironic twist, Parker Gates had turned ATC down in 1959 when they asked Gates to manufacture their first cart decks. He believed that the ST-101 would be a superior spot playback device. He was also concerned about potential legal issues related to mixing the ST-101’s and ATC’s patents, according to an interview with ATC’s Jack Bailey.
By 1966, Harris-Gates had acquired ATC, stating that ATC products would continue to be made in Bloomington. In 1969, Gates moved ATC manufacturing to Quincy, Ill.
Sources for this article include “Archaeology of the Broadcast Tape Cartridge,” an unpublished paper by Dr. David MacFarland; “Tape Cartridge Machine History” by Andy Rector, 2009; “Gates Spot Tape Recorder” by Jay Blakesley, Gates Radio Company Audio Sales Manager, NAB Technical Papers, 1959; the April 1959 issue of “Gates Studio Review”; the 1962 Gates General Equipment Catalog; “The Pantagraph,” Bloomington, Ill., May 9, 1966; and the website The Broadcast Archive.
