The Hornby pricing is what Hornby offered by mail-order from them. That would represent the Manufacturer's Suggested Retail Price.
For comparison, the same issue showed a Bowser ready to run PRR K4 for $10 less. To equip yourself with a master unit and three slaves, it would cost you $300. Or about $700 today (2008, based on the CPI). Decoders for your locomotives would be about $56 ea.
So DCC is not that expensive. Plus you can get sound, and can run more than 16 locomotives.
If anyone has more images to add, please do! I haven't seen too many of these systems, and I really don't want to scan pictures out of magazines because that might open a whole new can of worms.
Lionel Electronic Control
Information on this system was gleaned from an ad in the Dec 1946 issue of the Model Craftsman. Lionel claimed it was exclusive to Lionel, and the first time in the world for a system like this. Further info, including a complete service manual, was found on the internet. The ad was scanned from the Dec 1946 issue of Model Craftsman. Not sure about the status after 60 or more years.
For comparison, the $75 price on the set would have been equivalent to over $800 in 2008.
(Model Craftsman is better known today as Railroad Model Craftsman.)
More info is needed. Did this system actually have enough sales to pay for a full page ad in MR?
U$925 in 1976 (a copy of MR was $1) would be like $3000 today. For six locomotives. The Zero1 which showed up a few years later would have been half the price (digital is usually cheaper than analog). Yet people today complain about the cost of a basic decoder, or even the cost of a Tsunami... They are getting a bargain!
Revisions September 2012
Due to the fact the article is getting long and hard to manage, I moved the Zero 1 information to its own page, and will also do that for ASTRAC.
Also adding hyperlinks to make the page more interactive.
There is legend of a command control system with 20 channels being introduced in Europe back in 1972, but no information has been found about this system.