PDP-11's DECcasete

From: allisonp_at_world.std.com <(allisonp_at_world.std.com)>
Date: Thu Mar 16 07:55:30 2000

> > structural test sytem. I's equiped with DECcassete drive (it looks like
> > normal audio cassete).
> > Is there any replacement for them ? I mean using good audio casset or
> > so.
>
> Replacement for which, the media, or the whole drive?
>
> DEC claimed that you couldn't use regular audio cassettes with the TU60
> because they couldn't handle the high tension used by the drive. Sounds like
> it could be hype but you never know. I mean, what's the point of building a
> peripheral that uses regular audio cassettes, except that it *doesn't* use
> regular audio cassettes? Worst of both worlds.

First the recording is not audio it's Phase encoded saturation. Second
the media is very different from audion and used a coated binder. Audio
tape may work but not nearly as well. The file system if used is block
structured.

> As for drives, I don't know of any aftermarket TU60 hardware clone. However,
> if you're willing to replace the entire system with a software emulator,
> Ersatz-11 includes TU60 emulation, using tape image files for media (the "full"
> version of E11 can also use SCSI tapes as the physical medium for the TU60
> but that seems like overkill, I mean how many GB of data do you really need
> to store on one emulated ~90 KB cassette? :-) Information is on www.dbit.com,
> and the command you use to create a TU60 drive is "MOUNT CT0: file.tap".

Tu58s are findable and would make a suitable substitute at 256k a cart.
But the OS support may be TU60 specific.

Allison
Received on Thu Mar 16 2000 - 07:55:30 GMT