A DAT tape compared with an analog Compact Cassette, and lurking in the background, the first iPod which replaced both kinds of Walkman as a personal music player.

The uncertainty and bad press from the record industry hindered wide public adoption of DAT, but it earned a prominent place in the recording and broadcast industries. Professional DAT decks have switchable SCMS circuits which can prevent copies, allow one copy, or unlimited copies. Portable DAT Walkman recorders became de rigeur among the taper section at Grateful Dead concerts, and many Deadheads bought “pro” DAT machines to copy and trade tapes.

In 1988 my main interest was preserving 10-year old analog open reel master tapes made in the 1970s, which were beginning to show playability problems, becoming sticky. I determined that analog copies from one DAT machine to another didn’t lose anywhere near as much as an analog reel-to-reel generation, so I settled on archiving to DAT, figuring I’d need to make new copies every decade or so as the tapes deteriorated. Another advantage is digital tapes don’t get noisier or distorted, suffer from wow or flutter as they age. They either play perfectly or they don’t play. You get perfect sound, or you get drop-outs and terrible distortion. As it has turned out, my DAT tapes have proven to last a lot longer than the machines used to play them. The tape itself is very thin and if the deck malfunctions, it is likely to crease and damage the tape, causing drop-outs. Otherwise, the earliest tapes play the same as they did 30 years ago.

Which brings us to the subject at hand, restoring some old DAT decks. Over the last five or ten years, my Sony TCD-D3 portable DAT Walkman and DTC--700 home deck have become more and more unreliable. I was able to get the DTC-700 to play well enough to transfer most tapes via the SPDIF digital output to my computer for archiving on CD-R, but it needed a very delicate alignment to do so without errors. I had more or less given up on my DAT tape archive. DAT machines were out of production and parts were no longer available. But then a couple of things happened. First, I stumbled across a YouTube channel where ‘12voltvids’ took his TCD-D3 apart and fixed it. That inspired me to try the same. https://www.youtube.com/watch?v=KzyBLeBIj40&t=33s

The same guy dug into a DTC-75ES, which is a copper-plated version of my DTC-700.


Those videos revealed several weaknesses and common faults of Sony’s recorders that are known to repairmen. In particular, the bad electrolytics hidden inside the soldered-shut head preamplifier can. With the preamp recapped, my DTC-700 was good as new. It had previously suffered a broken mode switch gear, another common Sony defect, and I’d done a shade-tree fix.

A couple of additional websites for troubleshooting DATs are:




These entries are ten or more years old, so parts availability has gotten worse, but there is a lot of good information, and you may find your symptoms described, along with a lot of useful general discussion of how to set up these decks.

Then one day browsing Craigslist, I saw a group of three DAT decks, not working, for parts only, for $35. One was a DTC-75ES - same as my 700, and I thought, “Aha! A place to steal a gear for the mode switch, and maybe a newer set of heads.” So I bought the three decks, the Sony DTC-75ES, a Sony DTC-A6, and a TASCAM DA-302 dual-deck dubber. The story of those, along with a Panasonic SV-3800 which I submitted a low bid for on eBay and won, follows in the next articles.