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« on: August 01, 2014, 12:54:11 PM »
Good to hear happy ending Studer stories.
I still get amused and surprised at the level of design thoughts that went into Studer machines every time I have to deep dive into them with issues. However there are few things that I wish they had done differently.
From top of my head:
1) Use of the dreaded Frako caps... I am sure the cost was an important factor for the volume of electrolytic caps they used when tapes were in higher demands but using a little better quality electrolytic caps would have save thousands of hours over the years. A friend restores old German radios from 30's and 40's. Most of the electrolytic caps are still good in them even today after reforming them but the Frakos and small blue Philips caps in Studers are guaranteed to fail...
2) Use of poor quality inductors... In most of the capstan control boards for Studers, age will disintegrate ferrite core holding "wax" or plastic material, and they go out of adjustment. The moment one tries to put an adjustment screw on them, they fall apart... and no replacement inductors available.
3) Poor quality double sided boards ... many have found that removing components without fully melting the solder around the pins and leads while pulling on the part will most likely damage the through hole traces. It is a bigger problem for A80 boards.
4) Use of rechargeable MPU back up batteries... killer for A810s with 100% leaky batteries that will eat into the socket pins and the acid fume from the batteries dissolving circuit copper traces on the board while looking ok on the surface.
5) Use of switching power supply design for audio sections... this is true even for the top model - A820s. One of the reasons why external preamps sounding better.
Oh... I am sure there are more but enough for today!
Ki
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