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Old 21st Aug 2019, 10:14 am   #4
Studio263
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Join Date: Apr 2007
Location: Hampshire, UK.
Posts: 1,578
Default Re: Bang & olufsen 3300 type 1604 fuses

If you don't know, don't guess... Its one of these:

https://beocentral.com/beocenter3300

The fuses are on the top. You need to remove the aluminium panel that forms the top of the cabinet, the screws for this are under the black trim that runs across the back.

This model uses a crowbar circuit and will blow the fuses automatically (violently...!) if there is an excessive DC offset on either power amplifier output. Crumbling red electrolytics are the usual cause, check them all in both power amplifier modules and the power supply regulator panel. Note that some of them are reversible types, ordinary ones won't do. In extreme cases the output transistors may also be faulty so check these too. Diagnosis is difficult due to the pegboard chassis so its best to run the meter over every transistor and diode in the output stage modules is you find a faulty output transistor.
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