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I've built myself a slayer exciter and I am trying to measure the output voltage. I've created a coil with approximately 10 turns and soldered a bridge rectifier to the ends of the coil so I can measure DC. However, as I turn on the slayer exciter circuit, it messes around with the multimeter and reads the voltage as infinite. I've mitigated this problem a little bit by placing the multimeter out of the coil's "sight". However, the readings are still slightly bogus (maybe 1-3 volts).

How can I resolve this problem further?

Any help is appreciated.

Edit: I've come to the conclusion that this is a radiation problem and am looking for some ways to improve my situation. I've been informed about the option to buy a better multimeter, so any other fix would be nice.

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  • \$\begingroup\$ Sounds like plain interference. Also, what type of diodes make up this bridge? They should be schottky diodes like the 1N5817. You also need a filter capacitor after the diodes so the meter sees a smooth DC voltage. \$\endgroup\$ – Sparky256 Feb 2 '18 at 20:24
  • \$\begingroup\$ @Sparky256 Oh, it's a KBL406. I do have schottky diodes, so I can make one myself if I want to. \$\endgroup\$ – Erik Feb 2 '18 at 20:31
  • \$\begingroup\$ One thing to do is to add a Tekpower TP7040 to your toolset. This is one of those cases where this kind of meter has some advantages. Cheap to buy, too. \$\endgroup\$ – jonk Feb 2 '18 at 22:18
  • \$\begingroup\$ @jonk Hmm. Looks good for this application I suppose. However, I'm a student right now and I don't think my parents would buy something like that for me. Thanks for the advice, though. \$\endgroup\$ – Erik Feb 2 '18 at 22:35
  • \$\begingroup\$ @Erik Well, I can't solve that problem. But I paid US$23 for mine, delivered. Hopefully, your parents will see the light here at some point and realize the value of tools towards your education. \$\endgroup\$ – jonk Feb 2 '18 at 22:50
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Things did improve for you when you placed the DVM further away from the offending Slayer coil.This shows that this is a radiation problem .I have found that cheap DVMs can give bogus readings when working on Transmitters and large SMPS .Bypassing the red and black clip leads did little to improve this .If this was a conducted issue then filtering the leads would cure it .These observations occurred with a cheap Dick Smith Electronics DVM .There are now many chinese copies that look new but have the same old PCB in the shops waiting for some mug to buy them.In my experience the FLUKE does not do this .

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