stratfordade
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- Joined
- Feb 8, 2024
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I'm chasing a slight hum problem on an otherwise fine DSL401.
This may seem a daft question, but how is the main PCB grounded? The power receptacle ground is bolted into chassis but I see no spade connector leads from any PCB terminal going to any point on chassis.
I'm suspicious of grounding because I'm measuring about 5 ohms between anywhere meant to be grounded (e.g. the ground ends of the hum reduction resistors for the EL84s, centre terminal of bias adjust connector) and that power connector ground. Why isn't everything tied down to chassis ground?
Had the PCB out before to change some caps, but I want to leave in for now while I complete some tests so can't check any ground tracks on other side of PCB to see what connects them up, but I will be getting board out later.
Thanks for any pointers!
This may seem a daft question, but how is the main PCB grounded? The power receptacle ground is bolted into chassis but I see no spade connector leads from any PCB terminal going to any point on chassis.
I'm suspicious of grounding because I'm measuring about 5 ohms between anywhere meant to be grounded (e.g. the ground ends of the hum reduction resistors for the EL84s, centre terminal of bias adjust connector) and that power connector ground. Why isn't everything tied down to chassis ground?
Had the PCB out before to change some caps, but I want to leave in for now while I complete some tests so can't check any ground tracks on other side of PCB to see what connects them up, but I will be getting board out later.
Thanks for any pointers!