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Hickok 288x
#5

Hi Dave,

Unfortunately, the pic is not completely "painting" on my computer.

How big was the spark? I assume that your o'scope is grounded and your sig gen is not. If they are both grounded by 3 prong plugs there should be no spark.

Start out by ohming between the chassis and each pin on the power plug. the results should either be an open circuit or a high ohm reading, climbing to an open circuit (effect of the EMI caps charging).

Any steady Ohm reading would be bad; the lower the reading, the more the leakage. A very low reading indicates a short or miswire.

If this test passes, then:

Obtain a 1K 10 watt resistor. Connect 1 lead to the chassis, the other lead to ground. Connect a DVM set to 200VAC across the resistor. The leakage current = voltage / 1000, and should be less than 500uA (0.5mA). A Class A (residential) GFCI should trip at 5mA.

If the leakage is less than 1mA, then ground both the scope and the gen, then repeat testing the gen for output and continue troubleshooting.

hope that 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
Hickok 288x - by daveone23 - 10-14-2024, 03:27 PM
RE: Hickok 288x - by MrFixr55 - 10-14-2024, 04:50 PM
RE: Hickok 288x - by daveone23 - 10-14-2024, 05:40 PM
RE: Hickok 288x - by daveone23 - 10-14-2024, 07:27 PM
RE: Hickok 288x - by MrFixr55 - 10-14-2024, 07:43 PM
RE: Hickok 288x - by MrFixr55 - 10-14-2024, 08:04 PM
RE: Hickok 288x - by radiorich - 10-14-2024, 10:24 PM
RE: Hickok 288x - by daveone23 - 10-15-2024, 08:05 AM
462ron - by 462ron - 10-15-2024, 08:37 AM
RE: Hickok 288x - by daveone23 - 10-15-2024, 10:01 AM
RE: Hickok 288x - by daveone23 - 10-15-2024, 03:50 PM
RE: Hickok 288x - by daveone23 - 10-15-2024, 04:36 PM
462ron - by 462ron - 10-16-2024, 07:43 AM
RE: Hickok 288x - by daveone23 - 10-16-2024, 04:33 PM
RE: Hickok 288x - by MrFixr55 - 10-16-2024, 09:57 PM
RE: Hickok 288x - by daveone23 - 10-17-2024, 07:23 AM
RE: Hickok 288x - by daveone23 - 10-22-2024, 04:59 PM
RE: Hickok 288x - by MrFixr55 - 10-22-2024, 08:10 PM
RE: Hickok 288x - by daveone23 - 10-23-2024, 08:44 AM
RE: Hickok 288x - by daveone23 - 10-23-2024, 06:54 PM



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