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   James Morris (jmorris@social.kernel.org)'s status on Saturday, 03-Feb-2024 14:28:39 JST James Morris
   Finished making a thing. This is a power supply for the 30W 10 GHz amplifier I’m working on. It should also be able to power the transverter, IF radio, & relays. I’m resisting the temptation to add an MCU and display. For now.
   #hamradio #electronics #amateurradio #microwave #qro #sspa
   • Embed this notice
     James Morris (jmorris@social.kernel.org)'s status on Saturday, 03-Feb-2024 14:39:23 JST James Morris

     in reply to
     Using green wire for ground because the USA uses black for mains hot (active). I try and do this here when AC & DC are in the same enclosure. In Australia, brown is active and blue is neutral.
     Also, fwiw, mains voltage here is supplied to homes as 240v, split into 120+120, neutral is centre tapped. It is not 110, 115, or whatever else you see: it’s 120v. Heavy duty appliances typically have 240v supplies, and some people run 240v to an outlet in the garage.
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     James Morris (jmorris@social.kernel.org)'s status on Saturday, 03-Feb-2024 14:51:22 JST James Morris

     in reply to
     Also, re US vs .au, the way people talk about mains phases in the home can be confusing. Each 120v supply is called a phase, whereas if you have two 240v phases in .au, it's from a 3-phase feed. The 3-phase power I've seen in a person's garage here was 480v, which is getting well into catastrophic arc flash territory (search it up on youtube for an exciting time). People here very often do their own mains wiring mods, which is extremely unusual in Australia, I suspect in part because the default 240v is often lethal. Expect to die if you touch it.
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     Man aging with style (praxiscode@mastodon.online)'s status on Sunday, 04-Feb-2024 05:20:41 JST Man aging with style

     in reply to

     @jmorris
     I see you swapped out the connector on the panelpole. I had to do that, too, for my setup. Getting the pin out (and then back in again!) was a pain. Bench vise to the rescue.

     West Mountain Radio uses violet+black for 48v on their rigrunner.
     https://www.westmountainradio.com/product_info.php?products_id=rr_4008hv_p48
     I've seen orange+black or yellow+black for 24v/28v.

     James Morris likes this.
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     James Morris (jmorris@social.kernel.org)'s status on Sunday, 04-Feb-2024 05:21:08 JST James Morris

     in reply to

     • Man aging with style
     @praxiscode yeah, it was not fun getting that pin out.
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     penguin42 (penguin42@mastodon.org.uk)'s status on Monday, 05-Feb-2024 17:19:15 JST penguin42

     in reply to

     @jmorris In the UK we're also 240v, it's very rare to see 3 phase inside a normal house/garage. US 3-phase is much weirder, they have wildly different 3 phase voltages in different places.

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     Stefan Fendt🌻🟩 (stefanfendt@mastodon.social)'s status on Monday, 05-Feb-2024 17:21:50 JST Stefan Fendt🌻🟩

     in reply to

     @jmorris

     There is absolutely no risk of non-self-extinguishing arcs with 400V/480V circular AC.

     GB, Europe and Australia prove this. Every Day. For Decades, now...

     And it is a lot(!) more secure to accidently touch Europe's and Australia's live wire with 240V than US' 120V. Ever heard of RCDs?

   • Embed this notice
     James Morris (jmorris@social.kernel.org)'s status on Monday, 05-Feb-2024 17:21:50 JST James Morris

     in reply to

     • Stefan Fendt🌻🟩
     @stefanfendt there are RCDs (GFCIs) in the US on many outlets, especially near water or outside.
   • Embed this notice
     Stefan Fendt🌻🟩 (stefanfendt@mastodon.social)'s status on Monday, 05-Feb-2024 17:22:03 JST Stefan Fendt🌻🟩

     in reply to

     @jmorris

     In that case, if you count/calculate like that, we even have 400V AC for our homes, here in Europe...

     3 "hot" wires, 240V, 120° phase difference, each. Circular current. Usually coloured black, brown, grey.

     One neutral wire. Usually coloured blue.

     One PE "protective earth". Usually bi-coloured in yellow and green (green with a yellow stripe).

     All five come directly from the power network supplier.

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   • Embed this notice
     JamesB (mw1cgg@mastodon.radio)'s status on Monday, 05-Feb-2024 17:30:33 JST JamesB

     in reply to

     @jmorris 240V is not quite as dramatic as that. I've had a few shocks and it's not pleasant but it's not necessarily certain death in a lot of circumstances if you can break the connection between it and you.

     James Morris likes this.
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     James Morris (jmorris@social.kernel.org)'s status on Monday, 05-Feb-2024 17:31:18 JST James Morris

     in reply to

     • Stefan Fendt🌻🟩
     @stefanfendt this is what I'm referring to, 480v with all 3 phases shorted together, https://www.youtube.com/watch?v=kXO9GJXF1kg
   • Embed this notice
     Stefan Fendt🌻🟩 (stefanfendt@mastodon.social)'s status on Monday, 05-Feb-2024 19:25:34 JST Stefan Fendt🌻🟩

     in reply to

     @jmorris

     The difference is:

     We do not only have RCDs on lines "near water" or outside, but on every(!) line. Directly in the house's distribution box, not only for "chosen" outlets.

     We also have multiple arc-breakers, line-breakers, over-voltage protectors in the distribution box... for redundancy.

     Shorting all three phases (or just two of them), it's likely, that you just would see a little spark for about 20ms max (if at all) before at least one of four redundant breakers chimes in.

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   • Embed this notice
     Stefan Fendt🌻🟩 (stefanfendt@mastodon.social)'s status on Monday, 05-Feb-2024 19:25:49 JST Stefan Fendt🌻🟩

     in reply to

     @jmorris

     This only can happen, if you have no (or virtually no --> US) security devices in the installation.

     Every time I see US electrical house installations I am scared to my bones...

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     Man aging with style (praxiscode@mastodon.online)'s status on Monday, 05-Feb-2024 19:25:56 JST Man aging with style

     in reply to

     @jmorris
     I used a drill press with a drill bit mounted backward to push it out enough to grab onto it, and the bench vise to press it back in.

     James Morris likes this.
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     James Morris (jmorris@social.kernel.org)'s status on Monday, 05-Feb-2024 19:30:42 JST James Morris

     in reply to

     • penguin42
     @penguin42 that’s why we just mentioned the one 3 phase I’d seen. I don’t understand it in general.
   • Embed this notice
     James Morris (jmorris@social.kernel.org)'s status on Tuesday, 06-Feb-2024 06:46:30 JST James Morris

     in reply to

     • Stefan Fendt🌻🟩
     @stefanfendt good to know. I have seen main circuit RCDs for sale in the US, but they are in the hundreds of dollars and I don't know if or where they are required. No way a typical DIYer here is getting into that level of expense and expertise -- I assume any normal GFCI will trip on significant inductive or capacitative loads. People here expect such components to be very inexpensive.