In this 1972 amp, there is a .1uf cap from the power switch to the speaker ground, and also a .1uf across the power switch.
Should the latter one stay, or also go?
Thanks in advance.
![IMG_20240422_222617[1].jpg](https://www.diyaudio.com/community/attachments/img_20240422_222617-1-jpg.1302264/ "IMG_20240422_222617[1].jpg")
Should the latter one stay, or also go?
Thanks in advance.
The capacitor from the switch to speaker ground is alarming. Any capacitor whose failure could make terminals go live should be a Class Y and normally only 1 nF
Thanks very much, I was wondering what that cap across the switch was for.
The other, I assumed was a "death cap" (although it has a three-prong plug) because the filter cap negative grounds at that speaker ground. I took the cap out and will be replacing the filter caps as I restore this thing.
The other, I assumed was a "death cap" (although it has a three-prong plug) because the filter cap negative grounds at that speaker ground. I took the cap out and will be replacing the filter caps as I restore this thing.
Under no threat of firearm, do not ever reveal all relevant information in your opening post. 🙂
The question was not about the "death cap" connecting to the speaker output - it was about the other one across the power switch, and whether or not that was another 'death cap' that needed to be removed. So the three-prong cord is irrelevant.
It's in pretty plain English but the confusion is understandable. This is the kind of thing that gets resolved in two seconds in face to face conversation, and 48 hours on the internet. You should think twice before making that kind of comment. It's not good for YOU.
It's in pretty plain English but the confusion is understandable. This is the kind of thing that gets resolved in two seconds in face to face conversation, and 48 hours on the internet. You should think twice before making that kind of comment. It's not good for YOU.
looks like an old school ground polarity switch as in you can select which side of the AC line is grounded for "safety"...yeah right,not...that's got to go!!!
as to the other cap in question without seeing the full wiring scheme i've my doubts it's wired as described....
it's a double pole switch but is it two or three position?
as to the other cap in question without seeing the full wiring scheme i've my doubts it's wired as described....
it's a double pole switch but is it two or three position?
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Important to note that it is probably a guitar amp, as I can see a 1/4" jack and a panel with holes all lined up. This shouldn't be in the SS forum.
The "on-off-on" line reverse power switch (and the included "death cap" that gets switched from either the neutral or line connection to the chassis) was common on guitar amplifiers in the 1960s and 1970s (things were surely changed since, but I don't know what year) as a "safe" way to reduce hum, the bane of high-impedance (used in virtually all) electric guitar and bass pickups. I only recall these switches on guitar amps (both tube and transistor - I had two Heathkit solid-state amps wired this way, early 1970s). Is this a guitar amp? Were such switches ever used on other equipment?
I (only) suspect it IS wired as described, but the addition of the three-wire with-ground-connection power cord that was surely added later (we hope with the ground wire connected directly and firmly to the chassis) adds doubt. The switch wiring LOOKS original but one can't be sure.
But yes, whether it's tube or solid state, it should likely be in the Instruments and Amps forum.
I (only) suspect it IS wired as described, but the addition of the three-wire with-ground-connection power cord that was surely added later (we hope with the ground wire connected directly and firmly to the chassis) adds doubt. The switch wiring LOOKS original but one can't be sure.
But yes, whether it's tube or solid state, it should likely be in the Instruments and Amps forum.
If it is indeed a power switch, it must be an ON-Off-ON switch, otherwise it is just a polarity switch without turn off function.
