The design of the 33 was only a step further from the QC22. There’s a direct design line from the Quad QC1 and the QCII over the QC22 down to the 33:
The predecessor of the 33, the QC22, dates from before the use of PCBs:
The internals look somewhat complicated, even if the power supply is taken from the power amplifier.
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Yeah, the 33 has almost the same design language. The 22 was designed in 1959 so almost 10 years earlier. What a beauty!
Any other brands, apart from braun, going for this minimalist style at this age?
Any other brands, apart from braun, going for this minimalist style at this age?
please excuse going off topic momentarily...
should i be concerned? This is a recently refitted dual common mode four gang mains filter on light duty, the only caps that didn't get replaced were the two Rifa at the top, they seemed fine, measured with spec, prob late 1980's Mfr
The RIFA's that fail tend to be the ones with clear cases but given their history I think I would rather replace them. Always use Class X2 parts as shown in your picture as they are specifically for use in mains applications.
These are the common types that fail. When they fail they split and usually fill a room with smoke but they don't seem to go short and blow a fuse like you might expect. It has happened to me and I've seen many many failures in equipment over many years.
These are change on sight.
These are the common types that fail. When they fail they split and usually fill a room with smoke but they don't seem to go short and blow a fuse like you might expect. It has happened to me and I've seen many many failures in equipment over many years.
These are change on sight.
Good images, thanks. Nasty!
Oh yes, mains applications! my quick reference:
Its been a while since looking at that circuit and I'm not opening this up to clog this thread, but the cap of concern may be
a “Line-to-ground” line filter capacitor better replaced with Y2 or X1/Y2 safety capacitors. ( not solely X2 type).
“Across-the-line” capacitors should be replaced with type X2, X1/Y2 or Y2 safety capacitors.
Generally:
X type likely to fail to a short, trigger fuses MCB's etc, no fire.
Y type designed to fail open circuit. no shock hazard, but no filter.
But yes, the right thing in the right place critical for AC mains V filters.
Oh yes, mains applications! my quick reference:
Its been a while since looking at that circuit and I'm not opening this up to clog this thread, but the cap of concern may be
a “Line-to-ground” line filter capacitor better replaced with Y2 or X1/Y2 safety capacitors. ( not solely X2 type).
“Across-the-line” capacitors should be replaced with type X2, X1/Y2 or Y2 safety capacitors.
Generally:
X type likely to fail to a short, trigger fuses MCB's etc, no fire.
Y type designed to fail open circuit. no shock hazard, but no filter.
But yes, the right thing in the right place critical for AC mains V filters.
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