On Fri, 14 Apr 2017, Peter Cetinski wrote:
Lot?s of 3rd party devices that connected to the bus
appeared soon
thereafter. A few interesting ones I have other than the Voice
Synthesizer and the Vox Box
Those were sold under the Radio Shack name. There were also some similar
and better ones from third parties.
are an Exatron Stringy Floppy and a Cryptext
hardware encryption device.
There was a software intensive third party expansion bus serial printer
interface early on.
It was supplanted by the TRS-232 (cassette port to serial printer!)
(Not to be confused with numerous other products named "TRS-232")
In Googling for it, I stumbled on
http://ianmav.customer.netspace.net.au/trs80/
who makes a Model 1 to hard disk cable, a doubler, a CP/M "mapper", etc.