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ArgoNavis
2007-03-01, 02:36
Hello,

I installed an SB3 for a friend in another city. I used both the analog RCA connection, as well as the toslink optical. After about 10 months of faithful service, the optical connection packed up. The analog connection still works, fortunately.

Since it will be awhile before I can inspect the unit myself, I'm curious if anyone has any suggestions as to why the toslink connection may have failed, and how best to test such an optical connection.

It strikes me that there are a handful of possibilities:

The SB3 output may have failed,
The amplifier input may have failed,
The optical cable may have failed,
The cable may have become unplugged.

Does anyone have any suggestions as to the relative likelihood of these various possibilities? For example, is a toslink output circuit prone to failure in the SB3? Given that the cable is in an undisturbed location, are they known to spontaneously fail? Or, is there a chance that the toslink connectors work themselves loose with time?

Finally, what methods might one use to test the suspect components? Is there any way to test an optical cable? If it were a coax, I would use a VOM -- but I'm at a loss for optical cables. Is there some manner to verify that the SB3 optical output is functioning properly? Or, is one left with bringing extra cables and playing a game of mix-and-match to try and diagnose the problem?

Any advice would be most welcome. Thank you very much for your time!

AN.

SuperQ
2007-03-01, 09:44
Hello,

It strikes me that there are a handful of possibilities:

The SB3 output may have failed,
The amplifier input may have failed,
The optical cable may have failed,
The cable may have become unplugged.

Does anyone have any suggestions as to the relative likelihood of these various possibilities? For example, is a toslink output circuit prone to failure in the SB3? Given that the cable is in an undisturbed location, are they known to spontaneously fail? Or, is there a chance that the toslink connectors work themselves loose with time?h

AN.

Optical output is a visible (red) LED. it's possible to have it burn out. It's also possible, but less likely that the photodiode in the amp to have failed.

It is much more likely that the cable is loose.

If you see a red light out the back of the squeezebox, it's probably working.. if you can see the red light with the cable attached, it's probably working. If you can try a different input port on the amplifier, that would help.

If you see no light, or it's very dim, call Slimdevices, they'll ship you a new one. I would do this soon, so you can get it replaced for free under warranty! :-)

ArgoNavis
2007-03-06, 13:14
Hello, SuperQ:

I'm very grateful to you for your advice and suggestions! I managed to visit my friend's Squeezebox the other day, and it turns out you were completely correct in your suspicion that the cable connector had worked itself loose. For once a fix is quick and easy! :-)

Again, I really appreciate your taking the time to give me a little insight into what the problems might be.

AN.

seanadams
2007-03-06, 14:24
I'm glad you worked it out. To answer your question, I have never heard of an optical transmitter failing. It is a very simple device - just a transistor and an LED.