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City: Greenlawn
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Ed, I have one of these and the performance is rather surprising considering the 1.0 - 1.5W output stage. Having an 8" speaker and a solid state rectifier instead of a 35W4 certainly helps the performance of this unit.
The schematic is available on Nostalgia Air. Most of the caps in the set may be ceramic disks. The electrolytic on my et is still good.
Do be careful of these issues: - The set may have a 35B5 or a 35C5. They are not interchangeable; the basing diagrams are different.
- This is a true "Hot Chassis" set with the B- and low side of the filament string, along with the chassis connects to the power switch. This means that if the chassis is at neutral potential with the power switch closed, it will be hot with the switch open. and visa versa if the plug is reversed. The set does have an interlock. I would recommend installing a polarized plug and move the switch to the Hi side of the filament string and input to the rectifier, to ensure that the chassis is always at neutral potential.
- The rectifier is selenium. these do go bad and stink then they do.
Hope this helps.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Best Regards,
MrFixr55
Messages In This Thread
RE: Zenith H725 - by MrFixr55 - 03-17-2025, 10:24 PM
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