Over the last 45 years of service in the Electronics Industry, I have worked on anything from Coffee Pots, Rice cookers, VCR’s, Camcorders, Digital Betacam, and then Transmitters in the AM and FM Radio business. There is a lot to see. But in working on consumer tape decks and amplifiers there are a few things that stick out for anyone wishing to repair electronics should watch out for.
They can be things like poor wave soldering of the boards. There is so little solder on these parts that the smallest bump or vibration will cause a failure of that circuit. Multiply this by 100- 200 joints in a machine and you have a real good chance that it will need repair sooner rather than later. Other things that can break weak joints are conditions of thermal cycling. Does the part have a heat sink on it or does it get hot? Well so does the joint. So many cycles will make the solder joint weak and it was develop a ring around the part lead and again an intermittent connection or break. Corrections done by a good Technician who knows how to solder using Kester 44 (Lead) solder will do wonders for the longevity of the unit.
That is not the only thing that causes failure. There is the infamous 10 V Electrolytic capacitor. These 10 V types have proven a very high failure part so that I often tell others that I am allergic to 10 V caps. Many a tape deck or other equipment that have this part are on borrowed time from when they are made. I just was working on a Teac Z6000 tape deck. Playback was lost on the left channel. Further examination indicated that the coupling cap was defective and must have had a bad connection inside. What value was it? 220uFd/ 10V. Not the type of part I would expect in a $1500 tape deck. Don’t feel bad Teac, Revox and Uher have their Frako caps too. They are notorious for shorting.
7/18/16
OK, Now for the X series tape decks from Teac. Some think that having dual capstan drive is a plus. Technicians can tell you what a headache they can be. There is sensitivity to belt length, belt position, how clean the pinch rollers are and dirt on the capstan shaft. However, what causes me to write this is that I have also found the the two conditions that are seen are either Skew or tape looping. Looping is when the tape comes away from the heads making a perfect loop down below them. This is most likely caused by a loose belt. Most all X series need a 16.8″ belt but some sell 17″ belts that are near the limit to not use them. They sometimes do not work and if they do only for 6 month. Marrs has the good belts at 16.8″ X .330″ wide.
Next there is Skew. This is when the tape travels off the straight path at the pinch roller. I have determined recently that some genius adjusted the head position on the head block so that they are tilted and THIS make the tape skew. Of course the machine never works like they adjust them. Just go turning all the head screw and you are sure to make the deck better- Yes after about $160 of Technicians work. Rule is don’t touch these screws you need a lot to put them back into position.. Please,I have more than enough work already.
The best Service Manuals come from Stereomanuals.com . If I do not have one I need that is where I get them!
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Give them a call and see if they can help you. Tel: 604-514-1751 Talk to Curt. Email: info@reeltoreeltech.com