Right on! Sometimes what seems to be a simple question doesn't have a simple answer to go with it. I haven't had time to test the statements made in the conversation thread but there are enough source documents included to suggest they probably have it right.
Jerry On Wed, May 26, 2021, 11:47 AM Jesse Lafleur <[email protected]> wrote: > I love that someone has thoroughly investigated this, what a fun read! > > On Tue, May 25, 2021 at 10:58 PM Jerry Davis <[email protected]> wrote: > >> This discussion with attached source code and patent documents might help >> answer your question in detail: >> >> >> https://www.vcfed.org/forum/forum/genres/tandy-radio-shack/57410-story-behind-1500-baud-decisions >> >> Jerry >> >> On Tue, May 25, 2021, 9:42 PM Douglas Quagliana <[email protected]> >> wrote: >> >>> The official specs that I found for the cassette port say that it runs >>> at 1500 bps, but the bits are sent as a single 1200 Hz cycle or a single >>> 2400 Hz cycle so the length of a single bit varies depending on whether it >>> is a one or a zero. >>> >>> If you assumed an average density of ones and zeroes then the bit rate >>> would be the average or 1800bps, and if you said the user only "gets" eight >>> bits for every nine saved to tape then you would have 8/9th of 1800bps >>> which would be 1600, hmmm... that doesnt work out to 1500 either. >>> >>> So, how do you get 1500bps as the cassette data rate specification? >>> >>> Douglas >>> >>> >>> >>> >>>
