We have several of these large, wonderful machines. It’s not often we need or want to get involved in DAT repair as generally they are not easy to service machines and many key transport parts are becoming unavailable. The Sony 7030 DAT though has been designed with easy servicing in mind. There’s alot of room in these things and each section is clearly marked and separated into distinct boards much like Sony Broadcast video machines.

These are timecode DAT machines and were once common in video post production houses and the more well funded recording studios. The problem with some of this well built kit though is exactly that it works too well and gets left on for long periods through it’s life and this can take a toll on certain components, especially electrolytic capacitors. Heat builds up in electronic circuits, especially in switch mode power supplies that larger broadcast items often use. Capacitors have a rated life at 85°C or 105°C at several thousand hours. With hotter environments, substandard parts and long operating hours these capacitors can soon outlive their original design life.

Our 7030 DAT had started behaving oddly and at first the display would flash on and off after a short while powered on. Another machine would power up for 30 secs then just die. Before delving into the enormous service volumes it’s always worth replacing the Switch Mode Power Supplies (SMPS). These like many broadcast machines use supplies that are sometimes generic made by other companies and which can be bought at Farnell or RS. We did it the harder was and desoldered all the old capacitors in the power supply and replaced these with high quality low ESR Panasonic ones which should give us another 6000 hours of running time. So far this machine has worked perfectly although you do need good soldering and desoldering technique on these boards. A powered air desoldering station is a good idea, much, much better than a hand solder pump.

We have several time base correctors and frame synchronisers at our disposal. One recent addition is a new old stock (NOS) CEL Tetra. This is an early 1990′s motion adaptive Standards Converter for PAL, SECAM, NTSC 3.58 and NTSC 4.43 systems. A very flexible unit with composite, Y/C (S-Video), umatic DUB High Band/Low Band and component inputs and outputs.

Out unit still has it’s shipping caps over the BNC sockets and looks unused but after 5 minutes of power a cloud of white smoke billowed out of the cooling fan accompanied by a pungent smell. The Shaffner EMI mains filter had a nasty, sticky brown residue leaky out and all around the back of it. This is the second TBC that I’ve had this happen to. I’d assumed these units get left on for long periods when used in broadcast applications which would hasten their demise. According to their website, the mean time between failures (MTBF) of their recent products is around 2,000,000 hours! Our CEL TBC doesn’t look like it’s done more than 30 minutes so maybe there’s been some dodgy electrolytic fluid in these units just like the motherboard capacitor problems between 2000 and 2003.

We use time base correctors and frame synchronizers all the time in the transfer and digitising of analogue video tape.

One of our more flexible and high quality units had recently developed an annoying and very obvious fault on it’s video outputs. While the unit was working there were faint but distinct horizontal lines on the video. This phenomenon is often called a hum bar and can be caused by ground loops.

In this case we isolated the unit from the rest of our installation and using a separate power point the problem was still there. Looking at the unit itself it is a very deep and heavy 1U case with two 40mm cooling fans at the rear corners. It is quite old too and being designed for continuous studio use is likely to get hot and have been on for very long periods.

The video fault appeared to be AC ripple ‘riding’ on the DC power. It was time to look at the electrolytic capacitors in the power supply.

Although I could have tested each one, all these caps were old and only rated for 3000 hrs at 85 celcius so they all had to go! Here’s a list of them:

The only one hard to find was the large 400v dump one. Most units now are thinner and taller but eBay came to rescue here.

This shotgun approach worked beautifully and the fault had gone. While tracing the exact fault is always the best way, capacitor often get a hard life and will not last indefinitely, especially in switch mode power supplies.

Over the last 12 months we’ve seen this side of our business grow and adapt to the range of transfer needs that individuals, businesses and media creation organisations have.

We are able to support a wide range analogue and digital, consumer and professional video formats from the late 1970′s onwards such as: Betamax, VHS, SVHS, VHS-C, Video 2000, 8mm, Hi8, uMatic, Betacam, miniDV, DVCAM, etc.

We offer straight video transfer to DVD and a higher quality transfer service to DV or  uncompressed AVI which can then be supplied on hard drive, edited, encoded to a very high quality DVD or supplied on digital tape.

We pride ourself on our positive, friendly service and are happy to give advice over the phone or by email. When you call us you won’t be stuck in a voicemail system or told we’re an internet company so don’t like speaking on the phone!

Feel free to contact us by phone or email.

Focusrite Saffire LE

I’ve owned one of these Saffire LE firewire interfaces for a few years now and it’s very useful as a backup to my RME interfaces especially when I need to record and transfer audio at another location as it’s small, light and portable. It’s a very good sounding interface and  it even is reported to work under Linux which I’ve tried but unfortunately not with Audacity as this that doesn’t use the Jack server.

I’ve had an ongoing issue with the SPDIF inputs though. Under Windows XP and MacOS X it refuses to record more than a few mninutes if locked to another digital unit such as DAT machine and the Saffire software reports the firewire interface has lost it’s connection. This has rendered all SPDIF transfers impossible to do correctly.

The support at Focusrite is very good, you can actually speak to someone! We tried using an external power supply unit (PSU), different firewire cables, checking the type of firewire interface in the Windows machine and upgrading the firmware under MacOS X but all to no avail. This is a repeatable issue under several different computers and OS’s.

Are you fed up of sifting through all the, often Public Domain, PDF Service Manuals listed on eBay?

Apart from the fact that as many of them are public domain they are freely available to download they get in my way on searches for interesting old stuff. Take a search on Studer tonight, over 500 results and over 400 of these for service manuals or Studer documents for their reel to reel and other audio products from the past all of which can be downloaded from Studer’s public FTP server!!

I know some may call it legitimate business but I feel sorry for anyone who’s paid over a tenner (£10 GBP) for one even if it’s supplied on a nice shiny CDR or printed on laser paper and bound in a plastic wallet!

So, for everyone who likes to understand how things work and fix their own old equipment and not just throw it away, here’s some of my ‘favourite’ manuals that aren’t so easily available on the internet – for FREE!:

Tascam 112 Mk 1 Service Manual

Tascam 238 8 track Service Manual

Tascam DA88 DTRS 8 track service manual

Teac C-3x Service Manual

Nakamichi 610 Preamp Service Manual

Arcam Delta 70 CD player Service Manual

Philips CD104 Service Manual

NAD 3020 Service Manual