Hi everyone,
I have a Studer A721 that was given to me very recently and has come from a studio/radio station and it has not been in use for a number of years I imagine.
I have no experience of this deck and would like some advice on what could be the issue and where to start looking. All I can see so far is that upon applying power the relay clicks, the EOT red light is on and the capstans turn. Display does not illuminate so I cannot tell if the display is showing anything however none of the buttons are responsive.
Pressing the micro switches that are sitting right behind the cassette shell shows slow motion of the reel motors. This is all I can get out of the deck so far.
None of the 3 secondary fuses are blown, it still has all the original caps and the only measurements I took where the +/- voltages of around 22v from the 2 voltage stabilisers LM317/LM337. They measured about 5 volts higher than they should however.
I have not yet checked if I have a 5v supply as I stopped there and decided to ask for help here and hopefully what I describe above might ring a bell of common issues.
Any help would be greatly appreciated please so I get this wonderful deck going again.
Cheers 🥂
I have a Studer A721 that was given to me very recently and has come from a studio/radio station and it has not been in use for a number of years I imagine.
I have no experience of this deck and would like some advice on what could be the issue and where to start looking. All I can see so far is that upon applying power the relay clicks, the EOT red light is on and the capstans turn. Display does not illuminate so I cannot tell if the display is showing anything however none of the buttons are responsive.
Pressing the micro switches that are sitting right behind the cassette shell shows slow motion of the reel motors. This is all I can get out of the deck so far.
None of the 3 secondary fuses are blown, it still has all the original caps and the only measurements I took where the +/- voltages of around 22v from the 2 voltage stabilisers LM317/LM337. They measured about 5 volts higher than they should however.
I have not yet checked if I have a 5v supply as I stopped there and decided to ask for help here and hopefully what I describe above might ring a bell of common issues.
Any help would be greatly appreciated please so I get this wonderful deck going again.
Cheers 🥂
Thanks to everyone who helped and gave advice on this forum regarding the Studer A721.
The deck has been almost fully recapped by now (still awaiting a few caps that I ran out of stock to go onto the Dolby card). The mechanism has been cleaned and lubricated and apart from an alignment it's working beautifully, happy to report. Most of the issues must have solved themselves with recapping the deck.
i also took some time to fit IC sockets to certain ICs that i felt I might need easy access to on the system board and the remote interface board.
I replaced the LCD as the counter section had some faded segments on it (luckily I had a new display in my spares).
Cheers
Studer A721 test run - private video - YouTube
The deck has been almost fully recapped by now (still awaiting a few caps that I ran out of stock to go onto the Dolby card). The mechanism has been cleaned and lubricated and apart from an alignment it's working beautifully, happy to report. Most of the issues must have solved themselves with recapping the deck.
i also took some time to fit IC sockets to certain ICs that i felt I might need easy access to on the system board and the remote interface board.
I replaced the LCD as the counter section had some faded segments on it (luckily I had a new display in my spares).
Cheers
Studer A721 test run - private video - YouTube