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Everything posted by Craig Sawyers
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I've a similar cyclone (mine is plastic) bolted to the side of my shop vac. Amazing thing - all the machine tool shavings, including fine dust, end up in the cyclone, and nothing in the shop vac. So the filters in the vac don't get blocked up, and it retains maximum suction. But mine is passive. Yours seems to be a powered one? Yup - same make as yours but this one https://www.oneida-air.com/dust-deputy-deluxe-cyclone-separator-kit
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The Knuckledragger 3rd Memorial Slow Forum Post
Craig Sawyers replied to Knuckledragger's topic in Off Topic
Almost as bad as Bridge https://www.bridgebum.com/bridge_bidding_conventions.php . -
Bloody hell. I'd have ended in the ditch.
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My daughter surprised one in her armpit while she slept. So she got a nasty bite when she grabbed it in surprise. Her husband is an arborist (it is his company) https://www.gibbontrees.com/ . He was surprisingly unfazed by this, and reckoned he probably brought it home somewhere in his work clothes. So she ended up with the classic two-fang puncture in her armpit. She felt a bit sick was all, and a few ibuprofen was all that was needed. They live in Newcastle NSW. Mind you he found one in his UTE cab one morning, and even he did not want one along for the ride. So he ejected it with a leafblower.
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Current RIAA figures are out (link below). This is of course USA figures, but the headline is that vinyl record sales doubled in the first half of the year, with revenues now over 11% of paid for streaming. https://www.riaa.com/wp-content/uploads/2021/09/Mid-Year-2021-RIAA-Music-Revenue-Report.pdf
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You know, that makes me really glad to live in the UK - there are no animals that can kill you (unless you have an allergy to a sting). We have one poisonous snake - the adder - which is rare (I've only ever seen two), and the bite is no worse than a bee sting. And it is totally non aggressive. We have three stinging insects. The wasp, the hornet (wasp on steroids), and the bee. And one stinging plant - the nettle. And you can even eat that. Blanching kills the stings, and you can eat it as a salad leaf, or make it into soup. But the US pales into insignificance with poisonous things as compared with Australia, where our daughter lives. The working assumption is that any insect or snake is out to kill you, and many things in the sea too. The worst thing seems to be the Sydney Funnelweb spider. Not only is it venomous in the extreme, huge and ugly, it is also aggressive. If it takes a dislike to you the darned thing can jump 18 inches with fangs bared. Google it. Of course some things just try to eat you outright. Like saltwater crocs or great white sharks.
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Just heard a long segment on the Today current affairs radio 4 programme (in the UK), about the ESA BepiColumbo mission to Mercury. It has just done its first flyby of Mercury - the first of 6 before it gets captured into orbit in 2025. My interest in this, is that I was overall project manager for one of the 12 instruments on board - the Mercury Imaging X-Ray Spectrometer. That uses X-Rays from the sun, the reflected X-Ray light from Mercury having the spectrum of the elements on the surface of the planet - so how much iron, silicon etc, with a 10km resolution. It was launched in October 2018 After shakedown to make sure everything worked after launch, it then did a maneuver past the earth to send it on its way to the inner planets. Since then it has done two Venus flybys and yesterday the first Mercury one. So why go to Mercury? First because it is a rocky planet that has never had an atmosphere, so to learn about how the earth might have formed, Mercury is a good place to learn. Also it is the second densest planet in the solar system - very close to the Earth's density. In addition it has a magnetic field (no-one knows why), and ice at the poles (which is weird given how close it is to the sun). US interest in Ariane 5, is that the James Webb Space Telescope will be launched on one of those, imminently.
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The Knuckledragger 3rd Memorial Slow Forum Post
Craig Sawyers replied to Knuckledragger's topic in Off Topic
Meanwhile, the latest initiative to solve the trucker crisis: -
Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
I'm talking rubbish - of course PSU2D can do CLC! -
Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
Except it doesn't do CLC filters. You can do RC, LC, or just C. He's just about to issue a new version, which *might* do CLC. OK - he's released it, and it looks like it indeed does CLC. Must have a play. -
Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
Maximum for a capacitor input is 60uF. So 220uF significantly exceeds spec for a GZ34, https://frank.pocnet.net/sheets/030/g/GZ34.pdf -
Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
What rectifier tube are you using Kevin? -
Have a fantastic day!
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Have a truly great one Wayne!
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The Knuckledragger 3rd Memorial Slow Forum Post
Craig Sawyers replied to Knuckledragger's topic in Off Topic
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The main thing for a workshop in an ex-garage is to make sure the floor slopes slightly downhill to the door to prevent rain ingress. Doesn't take much rake to be effective.
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Happy birthday!
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Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
You might end up with a soft start into the first C to protect the rectifier - and clearly the capacitor too!. Sort of timed relay shorting a resistor between rectifier and first C once the rectifier is nice and warm and the capacitor is charged via the limiting R. Or a MOSFET or similar device instead of a relay. What transformer is needed depends on the resistance of the inductor, the ripple on the first C (~3V p-p), and other resistive losses in the rectifier and winding resistances of the transformer itself. You could lose ~40V all told. -
Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
Are you talking about an LC filter following a tube rectifier, Kevin? -
Megatron Electrostatic Headphone Amplifier
Craig Sawyers replied to kevin gilmore's topic in Do It Yourself
Well candidly, fuck me. I've just dipped into this thread, and I feel the need to barf. I have never seen such a construction nightmare. Handmade dremel boards FFS. Ugh. And that was not the worst by a long chalk. When I started building amps aged 15-16 I was doing far, far better job than that nightmare. Although an early one is festering in the attic for decades I'll wager it would still power up fine. Bit of a labor of love Kevin to rebuild the horror show. -
That must have been a toasty ride!
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Heartfelt condolences.
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The Knuckledragger 3rd Memorial Slow Forum Post
Craig Sawyers replied to Knuckledragger's topic in Off Topic
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Commissioning a new PC, DELL Optiplex 7090. My son Rob came down and helped out, putting an addition 1G SSD in there, moving bookmarks across, and putting one of the spinning rust drives out the other PC in there will all the legacy files. It is physically tiny, in spite of the fact that it has an i7 processor. It even turns out it has a backup battery in the power supply. Anyway, it goes FAST! I've gone for LibreOffice to keep as far away from the Gates evil empire as possible, and eM Client email software.
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The Knuckledragger 3rd Memorial Slow Forum Post
Craig Sawyers replied to Knuckledragger's topic in Off Topic
Anybody notice the Latin name for the fish? Microbrachius dicki .