| Forum Home | ||||
| Press F1 | ||||
| Thread ID: 139702 | 2015-06-13 09:39:00 | A 1970s computer question for the old timers | Billy (6701) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 1402675 | 2015-06-13 09:39:00 | We are looking through some old documents from the 1970s. According to one, the commercial installation where my relation worked had "9 track 80 Kch tap decks". What does the 80 Kch refer to? The read speed in kilocharacters perhaps? Also what was the typical storage capacity of magnetic tapes in the 1970s? There must be an historical archive on the web somewhere. |
Billy (6701) | ||
| 1402676 | 2015-06-13 11:04:00 | I'm sorry I cant help you, but I was selling computers in the 1980's And when a manufacturer said that their product was revolutionary, what they really meant was that it goes round. (ha ha) |
Digby (677) | ||
| 1402677 | 2015-06-13 11:08:00 | It maybe this (en.wikipedia.org) | Speedy Gonzales (78) | ||
| 1402678 | 2015-06-13 20:26:00 | . What does the 80 Kch refer to? . Seems to be: Transfer rate 80 Kch/s . . |
pctek (84) | ||
| 1402679 | 2015-06-14 05:20:00 | It maybe this (en.wikipedia.org) J Wattie Canneries were one of the first companies to use these IBM mainframes. Our side of the merged company used ICL mainframe and eventually had to go with the IBM config. as Watties bought into IBM pcs' too. lurking. |
Lurking (218) | ||
| 1402680 | 2015-06-14 18:32:00 | I'm assuming it is meant to be Kch/s (kilo chars per sec) for transfer rate as the tape capacity was usually in Mch (Million chars) before it all started to change to bytes. You also could have come acrossed cpm (cards per minute) ratings to show equivalent speeds for tape. Magnetic tapes were sequential and very slow but 80 kch/s, seems to not be the case. In this sense, I would presume it to have indexed its locations to make it easier to find where it needed to be. It would be slow to start, as it'd need to rewind to the beginning (possibly). Storage capacity for a 9 track tape, hard to say, it depends on density (how many characters you can cram into a short length of tape) but that link by speedy shares more on that. If you look even further back in history, you'd see the beginning of the hard drive, you would even understand hard drives better as it still kept the same concept throughout. Size, material and things that improved speed. Cheers, KK |
Kame (312) | ||
| 1 | |||||