origins of IBM 3740 diskette format

[William Donzelli]

> 3740 DE (Data Entry) format actually had the option of 80 or 128 
> characters / "columns" per record. The basic 3741/3742 data entry
> station only did 80 characters per record, although the diskette
> sectors were always 128 data bytes. You had to order the optional
> feature (a plug-in ROM card) to support 128 characters per record.

There is an original 3741 Data Station manual up on Ebay right now. 

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=1247&item=5171239786

Darn tootin' I know the seller.

William Donzelli
aw288 at osfn.org