Thanks, I've decided to leave them alone, aside from fixing the exposed copper on the power cord with some liquid electrical tap. If I do decide to sell them, I'll make note of it in the description.
It's too tight inside for the effort to justify the results. Even replacing the power cord would likely Tae me hours.
You will see on the top amp under the IEC there is a symbol of a square within a square. This is indicating that the design of this amp is "double-insulated" aka "Class II". I would assume that the bottom amp is a similar class because it has a two-pin IEC, but in reality you can't assume anything,
In my country electrical standards require Class II devices to write the class or have the symbol for any Class II device, if it isn't marked the device is assumed to be a Class I device (electrically grounded).
Yes, the old devices often have a steel chassis and casing, no class II and they were built with just a 2 pin plug. Comparing these with todays class II 2 pin devices ... apples, oranges.
Agreed, but as far as I know, the Apt Holman stuff doesn't connect one side of the line cord to the chassis or float it with capacitors. It seems to be insulated but before the current standards/markings.
I tried looking once I had the chassis open, but I couldn't see, even with a flashlight and magnifier. I'd have to take out circuit boards, the large filter caps, and some components to see, even more to replace it.
See post #8 for pictures.
Steel cases in the seventies and no PE......so simply less attention to safety. A loose L wire connecting to casing would have meant electrical shock when touching a device. It was like that often in the past. It does not have to do with one side of the line cord to the chassis (which really is a crime seen through todays eyes) or to float it with capacitors. "classic" and "vintage" stuff often was not safe 🙂 Not speaking of apt Holman but in general, I see a lot of devices.
Please have a good look at todays class II devices and see what is done to prevent exactly that loose L wire touching any metal part...
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In the eyes of the safety people, there are two types of 'double-insulated' appliances (yep, they think that your audio component is an appliance).
1] a completely enclosed in an insulating material (like plastic or nylon) appliance.
2] a completely enclosed in an insulating material (like plastic or nylon) POWER SUPPLY. the appliance itself may have an exposed metal chassis.
Note: in the first type, do not modify the plastic/nylon enclosure to add a 'ground' wire to a internal metal chassis.
in the second type, a 'ground' wire may be added to the exposed metal chassis.
1] a completely enclosed in an insulating material (like plastic or nylon) appliance.
2] a completely enclosed in an insulating material (like plastic or nylon) POWER SUPPLY. the appliance itself may have an exposed metal chassis.
Note: in the first type, do not modify the plastic/nylon enclosure to add a 'ground' wire to a internal metal chassis.
in the second type, a 'ground' wire may be added to the exposed metal chassis.