------------------------------------------ From a DAT-HEAD working for a large manufacturer of DAT equipment: ------------------------------------------------------------------ Pesonally, I want my D-7 to last as long as possible, and I make sure it is clean before any important recordings are made on it. I do not use the cleaning cassette though, I prefer to use alcohol and cleaning cloth. I do not use it for playback very often either, and that will make it last longer. I just checked the manual for the DTC-A8, and it says "Prolonged operation will cause contamination of the head. to obtain the best possible recording and playback sound, we recommend that you use the Sony DT-10CL cleaning Cassette (not supplied) to clean the heads after every ten hours or so of operation." Something to keep in mind is the "or so" part. Also this means 10 seconds only. A side note about the A8: The display flashes "CLEANING" for about 10 seconds on power up, after ten hours of use. It also says "Clean the head with the cleaning cassette when the deck has not been used for a long period of time. Contamination of the head may cause sound drop-out on playback." For the PCM-7030 and 7050 they say to use the cleaning tape once a week, but never more than 30 seconds at a time, and to perform manual cleaning with alcohol once a month. These machines have a chart in the Sercice Manual that says to replace the head drum, pinch roller and a few other parts (specific to that transport) after 1500 hours. The thing to remember is that Sony only recommends the DT-10CL tape, and that it's use has been factored into the recommended service intervals, like changing the heads, cleaning the transport, etc. So, if you use the cleaning cassette every week (about 10 hours of tape time or more) you can be sure to get at least 1500 hours out of a head drum on a PCM-7030. DTC-D7 and D8 do not have the chart that says when to change the drum, and I do not know how long the heads actually last. Using the cleaning cassette will shorten the life by some amount, but the trade off is reliability. If you clean the heads before a Once-In-A-Lifetime recording, you can be sure that the heads will not clog for at least 10 hours. If the machine has not been cleaned for months, who knows? Incidentally, the part about no more than 30 seconds of cleaning tape use at one time prevents overheating the heads (sandpaper generates heat). if you Play it too long the heads can actually crack. I have seen several video heads under a microcsope that had big chunks missing along both sides, and cases where the gap seperated. -M ------------------------------------------ From: Flawn Williams (FFWILLIAMS@npr.org) Organization: National Public Radio ------------------------------------------ Cleaning is a very dicey proposition. Regular DAT tape itself has some abrasives built into the coated mix, to keep little bits of junk from building up. So running a good-quality regular DAT tape is on one level keeping the deck clean. Particularly in cue or review (faster tape motion combined with play) this can help keep guides clear. DAT cleaning tapes are chrome rather than pure ferric metal...they are more abrasive, to get at built-up junk. They also abrade the heads more rapidly, so are not recommended for frequent use. Cleaning with foam swabs and cleaning solution is the most thorough and successful measure, IF you can get at the tape path. Some machines make that easy, but for most it's a pain in the butt. Some radio users that I talk to clean their heads weekly like clockwork. Some have machines they've used for years and NEVER cleaned the heads. No statistical correlation with more or fewer problems one way or the other. --------------------------------- In the meantime a gained some interesting knowledge about my TCD-D3. I shall list them, so perhaps it is possible to include them somewhere in this homepage. Head-cylinder wear-off: My new TCD-D3 needed a new head after only about 600 hours of use. This meant that I needed I new head-assembly (about DGL 240,-) and some other parts. The reason for the wear-off was a high tape torque. In the beginning I regularly cleaned the head, but it was not possible to remove the clearly visible "Dust-circle" on the cylinder at the height of where the two heads where. So if anyone sees a suspected "dust-circle" at the DAT's head, one should replace some parts which are responsable for the torque. (Contact me for details) Symptoms together with this were: FF & Rew was sometimes very problematic at the beginning of the tape. Some gears produced loud unhealthy rattling sound. Marc Nijdam E-mail: http://www.nijdam.de/marc.html