> > ---------- Forwarded message ---------- > From: Paul Koning <[email protected]> > To: "[email protected]" <[email protected]> > Cc: > Bcc: > Date: Sun, 2 Nov 2025 14:43:49 -0500 > Subject: [cctalk] Re: How hard would it be to make new dec tape media? > > > > On Nov 2, 2025, at 10:46 AM, Jon Elson via cctalk <[email protected]> > wrote: > > > > On 11/1/25 20:49, ben via cctalk wrote: > >> How hard would it be to make new dec tape media? > >> 60 year tape could use a replacement. > >> Ben. > >> > > DecTape is laminated, ie. it has Mylar on both sides of the oxide. 50 > years ago, we made working replacements from 3/4" instrumentation tape, but > it was NOT laminated. It had a print-through issue where if left sitting > for a few months, it would start getting errors. I have no idea if there > is anywhere you can buy 3/4" instrumentation tape. Maybe you can get 3/4" > video tape. > > Bitsavers has the 3M spec for 480 and 481 sandwich tape, I'm not sure > which of these two is what DEC used. It seems crazy, but it can't hurt to > ask 3M if they still make that stuff. > > paul
10-20 years ago I had a good Point-of-Contact (POC) at 3M (before we both retired). I asked him whether they still (at that time) made DECtape media and was told that 3M had sold their magnetic media operations to another company who also got out of the business before I contacted them. I also asked my POC (and the contact at the other company) if any DECtape media had been kept in a warehouse or similar -- he checked 3M's inventory system and told me that they had no record of any remaining DECtape media. The other company's contact had a similar "you've struck out" story. Bob P.S. I thought that I read here or in a PDP-8-specific forum/mail-list that DECtape wasn't actually laminated on both sides, which apparently explained the visible red oxide material removed from dirty DECtapes while cleaning them (per whoever posted their observations)?
