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Brian told me that the Sidewinder was originally designed to operate at 30 inches per second (tape speed), but that every couple of years this speed seemed to double. The servo motors that ran the takeup reels were never designed to operate at the higher speeds that were being demanded of them. Ted Hofbauer was the mechanical designer and Darrell Sholten's brother was the electrical designer.

In a manner that was to be echoed so many times in Silicon Valley in later years, he said that the electrical components were basically salvaged from a scrap pile. The servo motors were industrial surplus and the servo amplifier was a modified copy of the servo amplifier used in Gauss duplicating slaves.

The cue amplifier was actually an audio amplifier made by Amperex (not Ampex). LAP had used it as part of the portable phonograph product years before the Sidewinder had been invented. These amplifiers were basically just leftovers.

At the ever higher tape speeds, the servo motor response maxed out and couldn't perform the rapid change of speed necessary for the hub changes. Brian solved this problem by adding a servo boost relay which was triggered by the cue tone (aka: tailor tone). It temporarily decreased the feedback arm bulb ("exciter") brightness and cause the servo amplifier to receive a "go fast" signal. This happened a split second before the slide actually switched hubs and just before the motor actually needed to speed up. By doing this the motor could accelerate in time to accommodate the rapid change in speed. It was in his own words "a cheap and dirty fix", but it worked well.

The tone cue amplifiers were extremely noisy and occasionally misfired. Better shielding and a balanced line input configuration might have improved the situation, but still in all it worked.

Brian recalls that in later years, the Sidewinders achieved a 120 inch per second processing speed (about 3x the speed we ran at Ampex), largely due to innovations he made in the servo motor drives.

He praised the original slide mechanism and trigger circuitry, noting that he probably couldn't devise a better scheme even today. Even so, a new and improved version of the Sidewinder was being planned at the time business conditions finally caught up with LAP.

Drawing of a Sidewinder by Ron Schaer

If this new design had been built, it would have had a single piece cast frame (instead of a bolted and pinned assemblage of non-square pieces). It would have had a direct drive coupling between the servo motor and the hub shaft instead of the older rubber roller (edge) drive. This would have prevented slippage. The servo amplifier, instead of having a single output drive transistor like the ones I worked on, would have had RCA high power operational amplifiers. These would have provided not only precision and high power drive, but also braking functions.

Brian's opinion was that the Sidewinder actually added extra unnecessary steps to the production process when used in the the manner that most of their customers used them. Most duplicators recorded entire reels of tape much like Ampex did with open reel recordings. They would then de-reel the recorded tape into Sidewinders as a completely separate operation. The advantage to this was that the recorded tape could be QC'd before it was reeled and cut. In fact, the reel of tape could be degaussed (erased) and re-recorded if anything was amiss. The disadvantage is of course that a separate operation was required.

Ampex on the other hand used the Sidewinders in a more efficient manner, mounting them directly onto the output sides of the recorder decks and winding the recorded tape straight to the 8-track hubs. According to Brian, this was the way they were intended to be used. Other duplicating firms used the same finishing processes as Ampex, stacking the hubs, winding them, clipping and separating the hubs, and then splicing and casing them. He did say that many of LAP's own internal operations were done by hand (LAP was also a tape duplicator facility), and described their entire factory as a "stalled prototype".

Brian left LAP upon its demise and went to work for another duplicating facility named "ASR", and later worked for Bonneville Communications. This was owned by the founder of Electrosound, and they produced millions of 8-tracks per year. They used Electrosound equipment which loaded 8-track cartridges one at a time, cut the tape on a 45 degree bias at the cue tone, and left a couple of ends for the operator to splice. Similar to Ampex, the hub was then placed into the bottom shell half and the splice was made using a vacuum-assisted splicing block. A mechanism applied the foil strip and cut the edges in one stroke.

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