|LabGuy's World: Precision Echo 521
Coniscan Format Airborne Video Tape Recorder
Here is a rare oddity. This is a one inch video tape recorder used for airborne military operations. This function is usually referred to as a gun camera, as it recorded the image of the targets chosen by the pilot. This machine is late 1960s technology as far as I can determine via quick examination. I have very little information on the Precision Echo company and no information on this deck aside from what is printed on it. I have another recorder, obviously related to this one, a [Westel WR-201 airborne recorder] and it does have info printed on it.
The only other info I have, shown in my Catalog Pages, is for a man carried portable recorder by the Westel company of Mountain View California, dated July 1966. There seems to be a strong connection between several different companies putting there different brands on these recorders. Read on.
In the photos we see the threading diagram. What a complex little sucker to load! The large black rubber cylinder in some of the pictures is the capstan. The rubber is in excellent condition which is very rare. There appears to be no local controls on the transport. It can only be operated through the remote connector on the end of the VTR. There is an erase head and a video output jack, so I will presume this deck is capable of playback as well as recording. The reels are held in place by some very fancy cam locking mechanisms on the coaxially stacked hubs. This machine is in very good shape. It may be restored, possibly, and it displays nicely.
The tag on the Westel machine describes it as follows: Airborne video tape recorder for 875 line 1 volt video in accordance with EIA STD. RS-343 with equalizing pulses and serrated vertical sync interval 60 fields / 30 frames / second. That is pretty detailed information... as far as it goes. I will presume that most of this information applies to the Precision Echo machine too. The tag also reads: See manual 1501-0050 before use. If you have a copy of this manual or any other information on these airborne video tape recorders, feel free to drop me a line!
For a one inch VTR, it is very light, weighing in at only 44 pounds. The unit, with the covers on it, is a very compact 18 inches by 12 inches by 6.5 inches, slightly larger than the Westel recorder. It takes a larger 10.5 inch diameter standard NAB hub reels of one inch videotape. It is controlled remotely and receives, I presume, 400 Hz AC power from the air craft. More information needed, please.
Precision Echo Model WR-441 Video Tape Recorder
Above is an example of the type of deck that might play the tapes made by the WR-201. It is the Precision Echo WR-441. Note the similarity in model number to the Westel unit, yet the difference in the manufacturers name. It does match perfectly with the Precision Echo 521 though.
The pictured unit turned up on Ebay some time in the past. I obviously wanted this machine, but just as obviously, it is just a smidge bigger than a bread box! The head scanner is identical to the one on the airborne VTR. I had a few of the vide head scanners (only) that match the scanner on this unit perfectly. The scanners that I had were branded "Echo Science", but were otherwise identical. I have since sold them.
This is a special VTR that was developed for the military. It was used to record 'Gun Camera' footage in various aircraft. To withstand the high G forces encounteres in such aircraft, it employed a small scanner (about the size of type 1" B) and high rotational speeds. The 24 hz frame rate was chosen to make it compatible with film. To compensate for the low frame rate, the line count was increased to 655 lines (H rate somewhere around 15,720 Hz). Besides the miltary, some filmmakers used this format. The main use was special effects ('2001 - A Space Oddssey' had effects done in this format), but at least one feature film ('Tootsie'?) was apparently shot in this format. Before my collecting days, I had a chance to own one of these VTR's and passed it by! I now deeply regret it. Later on, a 655/24 adaption was made of the 3/4" U-matic format. Read more about it on the U-matic entry. Westel also developed an NTSC version of the machine for broadcast use, but was never sucessful in marketing it. One of the people working for Westel was quad pioneer Alex Maxey.
I believe that some of the information above is incorrect. My Westel WR-201 is clearly marked as operating at 875 line / 30 frame rate. That is not to say there were other scan rates, but I don't know how common that may have been. Any contributions of accurate information on this topic will be greatly appreciated.
I have also seen the brands Arvin Echo and Precision Echo. I believe these to be collaborative products, produced under government contract. Combining the products and skills of the appropriate companies, produced the product required by the need of the day. Precision corp. produced video recorders and Arvin Echo produced a still frame video recorder that used a super sized floppy disc. Any information on any of these companies or combinations of companies would be greatly appreciated.
NEEDED: Service manual and or Operators manual and or any other literature about this product. Need to locate a remote control head and wiring diagram for this recorder. Also need a compatible tape player. :-)
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Created August 12, 2006 Last updated: August 12, 2006