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turretslug · 15th Aug 2018, 7:26 pm

There are a few things that can cause this, but a classic fault is shorted diodes in secondary side rectifiers- I don't have the circuit to hand but I recall a similar fault in a Leak 3400 (badge-engineered Rotel) whose fuses were in either limb of the centre-tapped PA secondary. If you have a digital multimeter with a diode test function, this can be a convenient go/no-go in-circuit tester. This would be a "good news" sort of fault- something like shorted output transistors would be less good news.

15th Aug 2018, 7:26 pm	#2
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,398	Re: Fuses keep blowing on Rotel rx400 amp There are a few things that can cause this, but a classic fault is shorted diodes in secondary side rectifiers- I don't have the circuit to hand but I recall a similar fault in a Leak 3400 (badge-engineered Rotel) whose fuses were in either limb of the centre-tapped PA secondary. If you have a digital multimeter with a diode test function, this can be a convenient go/no-go in-circuit tester. This would be a "good news" sort of fault- something like shorted output transistors would be less good news.