This is the Ampex TV Equipment Section of
The Broadcast Archive
Maintained by:
Barry Mishkind - The Eclectic Engineer
With the kind assistance of Xen Scott
Latest Update 2/28/04
AMPEX VR-3000
Xen Scott recalls: "The VR-3000 was a special purpose machine that was designed for field recording where the use of a full size videotape machine was impossible or undesirable. A portable, two-inch quad-head VTR, it was built into a suitcase, used 20 minute reels and was capable of high-band recording. It could be battery powered or operated on AC.
"The VR-3000 was a very unusual machine. It's not easy to compress a two inch quad head videotape machine into a suitcase so it could be carried while recording and powered from batteries when desired. Fortunately, I never had to carry the 55 pound VR-3000 while in operation. The VR-3000 could record in high-band or selected low-band standards using two-inch videotape on 20 minute reels. The recorded tapes would play on any two-inch, four head videotape machine. Video playback from the VR-3000 was from the demodulator output with no timebase correction, so VR-3000 playbacks were only good for monitoring and confirming that a recording had been made.
"The VR-3000 had no erase capability. All recording had to be done on blank tape. Most of the forward tape motion was provided by the takeup reel. The rubberized capstan, without a pinch roller, was used for maintaining correct speed within the range developed by the reel servos. The tensioning force delivered by the reel servos was controlled by strain gauges mounted on small tension arms in the tape path. Early model VR-3000's used resistive strain gauges. They were temperature sensitive and this resulted in severe tape speed errors when the ambient temperature was different than room temperature. Later model VR-3000's used capacitive strain gauges which were not sensitive to temperature. The special video record head used ball bearings in place of the air bearings found on video head assemblies used on full size videotape machines such as the VR-2000. Vacuum for the video head tape guide was provided by a built-in miniature vacuum pump."
Lytle Hoover notes: "An interesting sidebar to the portable VR3000 story, from our market research at RCA, we found the biggest user of the VR3000 was the US Navy. They had them on the aircraft carriers to do video documentation of the planes landing. A camera/VTR crew sat on the end of the flight deck recording the approaches and followed the plane down to the deck until it stopped.
"I promoted this portable VTR concept to the RCA management when I learned about our TPR-10 in the Government engineering labs at Bldg. 13. The RCA TPR-10 had been designed by the RCA Government engineering staff to only be a data intrumentation recorder using a quad VTR recorder headwheel(or alternate 8 head). Our B/C engineers helped do a redesign the TPR-10 to become a commercial TV video recorder."
If you have any old photos of Ampex equipment that operated at your TV facility which you would like to have in our Virtual Museum, please send them along, so we might add them to these pages.
