Greetings,
a couple of months ago I made a great found in the attic of my parents house. A cyrus two issue 07 and two mission loudspeakers. Asking my dad who they belong to, he told me he hasnt turned them on in twenty years and he was happy I wanted to make use of them again.
After a couple of test runs and a new alps blue poty(information received in this great forum), I had the system up and running pretty nicely.
Unfortunatly I wouldnt be writing this thread, if everything was still working fine. After having some friends visit for a weekend and using the system intensivly in the living room. When I moved the speakers back to my room, not thinking straight i plugged both sides of the output cable into ground of the right speaker...
I shorted the circuit. Just had the look at the amp. The upper fuse FS2 is blown, i am guessing thats F3.15A. Didnt see any other anomalies on the critical transistors and components of the protection circuit.
I'm not sure wether I should just replace the fuse and hope for the rest to be intact or if I have to take further percautions to make sure I dont break anything else when putting in a new fuse.
In the first case, where can I get an adequate replacement fuse?
Hoping for advice from some more experienced base addicts.
a couple of months ago I made a great found in the attic of my parents house. A cyrus two issue 07 and two mission loudspeakers. Asking my dad who they belong to, he told me he hasnt turned them on in twenty years and he was happy I wanted to make use of them again.
After a couple of test runs and a new alps blue poty(information received in this great forum), I had the system up and running pretty nicely.
Unfortunatly I wouldnt be writing this thread, if everything was still working fine. After having some friends visit for a weekend and using the system intensivly in the living room. When I moved the speakers back to my room, not thinking straight i plugged both sides of the output cable into ground of the right speaker...
I shorted the circuit. Just had the look at the amp. The upper fuse FS2 is blown, i am guessing thats F3.15A. Didnt see any other anomalies on the critical transistors and components of the protection circuit.
I'm not sure wether I should just replace the fuse and hope for the rest to be intact or if I have to take further percautions to make sure I dont break anything else when putting in a new fuse.
In the first case, where can I get an adequate replacement fuse?
Hoping for advice from some more experienced base addicts.
If you don't already have it, the service manual is available here: CYRUS TWO SERVICE MANUAL Pdf Download | ManualsLib
By FS2, I presume you mean the power supply fuse shown on page 29.
On page 91 you can see that the output transistors are protected by the fusible resistors R89 to R95 (indicated by exclamation marks in the power amp schematic) so they would be worth checking.
Fuses are readily available, depending on physical size - are you located in the UK?
If so, CPC stocks a variety: https://cpc.farnell.com/multicomp/mc000829/fuse-5x20mm-glass-quick-blow-3/dp/FF03076
By FS2, I presume you mean the power supply fuse shown on page 29.
On page 91 you can see that the output transistors are protected by the fusible resistors R89 to R95 (indicated by exclamation marks in the power amp schematic) so they would be worth checking.
Fuses are readily available, depending on physical size - are you located in the UK?
If so, CPC stocks a variety: https://cpc.farnell.com/multicomp/mc000829/fuse-5x20mm-glass-quick-blow-3/dp/FF03076
Thanks fort the reply. That is indeed the fuse that is blown. In the parts list the description is '4A Q/B fuse'.
The fusible resistors look normal to me. Is there any visible indication when they have fused?
I am situated in germany not the uk.
The fusible resistors look normal to me. Is there any visible indication when they have fused?
I am situated in germany not the uk.
4A quick blow (or fast acting) fuses are available in both 5mm x 20mm and 6.3mm x 32mm sizes. For example: https://cpc.farnell.com/webapp/wcs/...ategoryId=700000009745&pf=110142695,110193169 Is that what you want to know? Look for a local supplier. I would buy a pack of 10, replace the blown fuse and see what happens.
You would need to measure the resistance of the fusible resistors to see if they've gone open circuit.
Hopefully, someone with experience of the Cyrus 2 will chip in.
You would need to measure the resistance of the fusible resistors to see if they've gone open circuit.
Hopefully, someone with experience of the Cyrus 2 will chip in.