STUDER A820: Slow action of break; a quick fix

[yjwu]

I don't know whether you experienced this problem before: the release of break solenoid plunger of left spooling motor break of my STUDER A820 was prolonged to be about ten seconds. I tried to disassembled the break solenoid and hold it up right to test whether gravity will pull the plunger down after power off. As expected the plunger was stuck inside. My original thought was to switch left and right plunger and see whether mixing two will solve the problem. Then I came up an idea of adding a thin cushion, maybe a thin teflon washer, to the coned base as a separator. I managed to cut a 4mm diameter from wax backing of double sided tape and put inside the base of the plunger.
After some maneuvering I put the break solenoid back to working position. Pressing STOP for a few seconds and release both left and right plunger released without any delay. Problem solved!

Yeun-Jung Wu

 

[yjwu]

I don't know whether you experienced this problem before: the release of break solenoid plunger of left spooling motor break of my STUDER A820 was prolonged to be about ten seconds. I tried to disassembled the break solenoid and hold it up right to test whether gravity will pull the plunger down after power off. As expected the plunger was stuck inside. My original thought was to switch left and right plunger and see whether mixing two will solve the problem. Then I came up an idea of adding a thin cushion, maybe a thin teflon washer, to the coned base as a separator. I managed to cut a 4mm diameter from wax backing of double sided tape and put inside the base of the plunger.
After some maneuvering I put the break solenoid back to working position. Pressing STOP for a few seconds and release both left and right plunger released without any delay. Problem solved!

Yeun-Jung Wu

I got a good suggestion from a member of tapehead forum.

STUDER A820: Slow release of break; a quick fix

I don't know whether you experienced this problem before: the release of break solenoid plunger of left spooling motor break of my STUDER A820 was prolonged to be about ten seconds. I tried to disassembled the break solenoid and hold it up right to test whether gravity will pull the plunger down...

www.tapeheads.net

Now both solenoids worked as expected in their original state.

Yeun-Jung Wu

 

[yjwu]

I got a good suggestion from a member of tapehead forum.

STUDER A820: Slow release of break; a quick fix

I don't know whether you experienced this problem before: the release of break solenoid plunger of left spooling motor break of my STUDER A820 was prolonged to be about ten seconds. I tried to disassembled the break solenoid and hold it up right to test whether gravity will pull the plunger down...

www.tapeheads.net

Now both solenoids worked as expected in their original state.

Yeun-Jung Wu

I went back to my wax paper solution again since long press STOP or PLAY did create time lag between two plunger action. This lag can not be eliminated no matter how I screw those two hex.

Yeun-Jung Wu

 

[yjwu]

Further inspection revealed the cause behind the delay: missing part of the cushion?

Pictures shown the inside of the solenoid: Healthy one (Right picture) has a shinning reflective flat surface on the tip of the cone while that with delayed action (left picture) had a cushioned material exposed; there were sticky residue on the bottom of the coned plunger.