In one of Hagerman's tube preamp kits he had a series RC snubber across the secondary HV winding. My friend built it up and complained about hearing hum and buzz. When I finally understood him I realized he was talking about acoustic emission. He brought the unit over, and the noise was quite audible in a fairly noisy room. It was all from the capacitor, a high voltage ceramic disc which iirc was one of those with various agency certifications.
In US houses it's an either / or requirement.
Either it's measured under 25 Ohms or drive two ground rods.
Most residential electricians go with two ground rods.
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I discovered the singing because I was varying he sig gen f and driving about 30 V pk to pk on th output. X7R again. I have subsequently removed a few X7R MLCC's from my circuit. Bad stuff and really need to be applied very carefully and IMO no where near audio.
I sympathize with John - they all look the same in the junkbox. I struggle to make out resistor color codes these days without a magnifying glass, let alone the writing on TO92 devices. As for SMT: well, I prefer to work with parts I can actually see.
Ok time to let a secret out. The laser etched markings on semiconductors can best be read when under an "Artic Blue" light. That is light rich in near UV! I used an old "Tensor" lamp for this. It uses an automotive bulb and runs it at a volt or two above it's 12 volt design voltage. Lamp life is about 100 hours as compared to the 1000's of hours it should work in a car. I buy the light bulbs in boxes of ten.
Now for those who have never seen a Tensor lamp, it is a filament transformer in the base a thin gooseneck and then essentially a juice can for the reflector. The deluxe model has a high low switch for those who didn't like the short lamp life.
I would like to tell you it works for sorting resistors, but the problem there is that one manufacturers orange is anothers' red!
I have a large drawer with bins, every other bin is marked with a standard 5% value. Ones that are not a standard value go in the unmarked bin in between. For my good 1% resistors I keep them in a notebook with plastic pages having 12 pouches per page.
ES
Depending on what you were snubbing the screams would have drowned out the singing.
Do be careful what you touch. . .
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Demian,
Do I take that to mean you do not recommend learning bomb disposal by trial and error?
ES
Do I take that to mean you do not recommend learning bomb disposal by trial and error?
ES
To state the obvious:
And.... if the audio systems sounds bad, pull the rods, clean them, and re-drive them. Oxidization is a serious problem that can crop up disturbingly early in the given electrical install.
We are talking about impedance issues across a large load, and under complex outdoor environmental conditions...are we not?
When I go to a audio show I try to, if I can, to get across to the given show organizers..that they will probably have much better results at the show, regarding participant and public satisfaction if they do one thing. It can be inexpensive or is the most inexpensive upgrade they can ever enact, regarding 'sound quality' for a show. But it will cost money and it might be, due to the given hotel's operational guides, it may have to be done by the hotel's electricians. the given electrician may not see the sense in it, and the show organizer may have to add their own electrician into the mix to make sure it is actually done properly --not just billed to them (as an additional expense) properly.
And that is to have ever single breaker and every single screw connection in the given distribution boxes..reset by an electrician. this can avoid some of the noise, degradation and electrical failures at the given show. (once again, obvious stuff)
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Most aqueous solutions are conductive, to some extent. Very pure water is a much worse conductor, so conductivity can be used as a check on water purity. I seem to remember my ex-colleagues in the power industry use this technique to monitor boiler water, which has to be pure to reduce corrosion.john curl said:
The urine itself is conductive but the stream as a whole isn't as it normally breaks into droplets towards the impact zone - air is an excellent insulator.
First, of course, urine is conductive, all tap water is to some extent, but is it EXTRA conductive, like salt water, for example. In any case, just wetting the ground with water should increase conductivity, because of the added impurities to the water from the ground.
Second, don't try an electric fence, sometimes the 'stream' is not broken up as much as you might predict. I have seen pictures of the results.
Second, don't try an electric fence, sometimes the 'stream' is not broken up as much as you might predict. I have seen pictures of the results.
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