Here is a demo tape produced to promote the CMX 600, circa 1970, one of if not the very first non-linear, or in it's day "random access" editing systems.

And here are some of the specifications of said system:

Computer:

• DEC PDP -11
• 16,000 words of core memory (16 bit), or 32 k-bytes
• Blazing speed: 3 to 5 microseconds per instruction. (About 1000 times slower than a typical PC today.)
• No hard drive

Disk Pack Video Storage:

• Memorex digital disk drives
• Each about the size of a washing machine
• Drives modified to store and retrieve analog video signals
• Capacity: about 5 min video per disk pack
• Usually 4 to 6 drives per system, or 20 to 30 minutes of storage per system

Video System:

• Bandwidth of the disk drives was less than 1 MHz...hence black and white video, without compression
• Every other field of video was recorded on the disk packs, to extend storage capacity
• The "lost" field was recreated using a 1-field disk memory in the 600 main unit

Audio Encoding:

• Encoded as PCM data on the back porch of the video horizontal sync signal
• Plus: Could hear audio in still-frame, slow-mo, etc
• Minus: Quality poor, resulting from sampling problems due to jitter in the signal from the disk drives.

Light Pen Control:

• This was a technology used primarily by the military
• CBS wanted to avoid conventional controls, to minimize union jurisdiction issues
• It also provided some "gee-whiz" appeal
• The jitter again was due to jitter in the signal form the disk drives

Software Menus/Controls

The names of the controls on the screens and the logic of the operations were based on conversations with film editors, and observation of them cutting film. The goal was to make it as easy as possible for a film editor to operate the new system.

Thanks so much larry for making me feel OLD!   :)   Gosh has it been that long????????

Memories..........

Marianna

 Marianna, I hate to admit this but here goes...in the early 1970's I did some work with a company known as Teletronics in NYC that used one of these. NOW, who do you think is feeling old?

 I should also add an important addendum. In our business, we take entirely for granted freeze frames of images, viewable images in high scan forwards or backwards, slow motion, forward and reverse play - it's all so integral to the process. At the time, all video editing done was between two different 2 inch quad machines, where the editor only had a viewable picture in the normal play mode after a 10 second lock up interval, and that was it. The CMX 600 was truly revolutionary in giving the editor a viewable image throughout the entire process, ergo the strong focus on those features in the demo.

I saw one of the two 600s still in existence in 1984 at a post house in San Francisco.  At that stage it was being used as a video source for audio sweetening.  I don't know what happened to it subsequently.

Rolling back to 1973, I was working at Armstrong Audio-Video in Melbourne, a large video post facility.  AAV had the first PAL CMX 300, which was partly developed on site.  Dave Morgenstern from CMX handpatched the code of the NTSC original one octal byte at a time by toggling the front panel switches of the PDP-11.  Set address, set data, store.  Set address, set data, store.  When it was finished the patched program was then dumped back to punched paper tape, our high-speed storage medium.

To start up you manually toggled in a series of instructions that gave the PDP-11 enough intelligence to load that tape again.  I'm just so glad those days are gone!.

 2" tapes ah I have 2 reels of lowband 2" I can't find anywhere that will play them back.

Blue Crow:

 2" tapes ah I have 2 reels of lowband 2" I can't find anywhere that will play them back.

Daniel:

Here's someone who could possibly help you or if not, could probably steer you in the right direction, and right in your neck of the woods, too:

http://www.adaptiveconversions.co.uk/

Thanks Larry I'll contact them. I have 2 x 2" tapes of a small band called the Rolling Stones performing at the Marquee Club. An important part of British history which everyone should see.

wow, get those over to a decent format!  That should be great stuff!

switthaus:

wow, get those over to a decent format!  That should be great stuff!

I PM'ed him a personal contact of mine who can help him do exactly that.

 And for an even deeper trip down editing memory lane, go here. This is where the CMX 600 info came from.