If you're going to buy a used one, find one with a guarantee or one with a locked waveform displayed. If you're unsure, post a link to the one you're interested in here (or email it to me if you're concerned that someone may bid against you on it).
babin_perry@yahoo.com
The BK Precision 2120B was a good option for a new scope and still is if you can find one for about $400.
For used scopes, I recommend the 400 series (465B preferred) or the 2200 series Tektronix scopes. Avoid the 2400 series unless you can afford to lose whatever you paid for it.
For audio work, I'd avoid the purely digital scopes.
You can check the driver transistors in the circuit but unless they're shorted, it may be difficult to tell if they're otherwise defective (leaky or open).
babin_perry@yahoo.com
The BK Precision 2120B was a good option for a new scope and still is if you can find one for about $400.
For used scopes, I recommend the 400 series (465B preferred) or the 2200 series Tektronix scopes. Avoid the 2400 series unless you can afford to lose whatever you paid for it.
For audio work, I'd avoid the purely digital scopes.
You can check the driver transistors in the circuit but unless they're shorted, it may be difficult to tell if they're otherwise defective (leaky or open).
I think they only light up when something isn't right with the amp. They're not indicators, as far as I know, they were likely chosen as diodes with a specific forward voltage to serve as some sort of internal limiter. That's just a guess. I've repaired hundreds of these amps and have never had to be concerned with them.
The power supply drivers are SMD. The drivers for the outputs are a combination of through-hole transistors and one 8-pin SMD driver IC.
The power supply drivers are SMD. The drivers for the outputs are a combination of through-hole transistors and one 8-pin SMD driver IC.
If you have 80v on the speaker terminals, the power supply is functioning normally. The drivers that you need to check are for the output transistors, not the power supply transistors.
Did you replace output transistors or power supply transistors?
What were the part numbers on the original parts and the parts that you used as replacements?
Did you replace output transistors or power supply transistors?
What were the part numbers on the original parts and the parts that you used as replacements?
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