Re: CRT anode discharge
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Good to hear that, albeit painful, the anode charge should not be deadly. I choose to test neither.
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I guess one of the aspects I wanted to put out there was: follow safe practices. They work. My prior experiences that the anode was discharged by the time I was pulling the connector was probably leading me to complacency. I was about to grab it with pliers when I told myself, nah, put the ground on, do it one handed. Happy I did. The methodology works. I'm still curious why this one was so significant. I've pulled a freshly hot anode before, and nothing. Did Tek change hardware slightly to provide a slow leakage path? The HV line in this one is white, where the others I've dealt with are red. Plenty of carbonized crud around this one, as I've seen on others. The SN<250K CRT is different than the SN>250K. Was there a change in CRT construction/process that makes the later less capacitive? Fully grounded, Dave On Sunday, March 14, 2021, 02:57:10 PM PDT, Sean Turner <[email protected]> wrote:
I got zapped once by the residual charge in a 7904 crt. I would characterize it as no worse than a very strong static shock of the type that are common on a windy days in the American southwest (I've had some painful ones). However, this jumped a *much* larger gap!! Fortunately, the current is very low. If you're following standard good practices for working around this stuff like the OP was, very unlikely to kill you unless you have certain health problems already. Now, on the other hand, the B+ supplies in 500 series scopes we all love are low impedance and can supply significant current. Those should be treated with the utmost respect, as they will most certainly not suffer you to make the same mistake twice. Sean On Sun, Mar 14, 2021 at 01:54 PM, Tom Lee wrote:
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Dave Peterson