Notices by Neil G4DBN (g4dbn@mastodon.radio)

@schratze @gsuberland and yet I am sleep-deprived from total overload, don't have a TV, my next Youtube video is two days late, I have dozens of unread and unanswered emails. I'm self-medicating with 10 or more double-espressos a day (which is why I have time to type this)

@schratze @gsuberland To-Do lists are just a visible record of failure. I have IBNUs (Important but not Urgent) items still waiting for attention from 2009. Important like "leaking roof which is damaging the door, walls and ceilings" or "unfinished insulation which is wasting huge amounts form heat loss", or "Parts I promised to make 5 years and two months ago, and still have the items the friend sent me to adapt". Or the tax return that I'm being fined £10 a day for not finishing

@AlisonW I have been playing Melt-Banana, Shonen Knife and Three Trapped Tigers at volumes mandating ear defenders. Hope the neighbours like it as much as my dogs like their unpleasant explosives. Dogs are hiding beneath two quilts and a pile of pillows. Least I think that's where they are, it's very easy to mislay two Chihuahuas

@vkc I use DaVinci Resolve, which has an excellent transcription/caption generator that understands my Lincolnshire accent, and creates a timestamped .srt file. I always spend maybe an hour checking and editing the occasional homophone error and adjusting line endings and punctuation to make life easier for folks who need/want English captions. Also helps hugely with the significant proportion of my audience who use translation

@ftg @azonenberg @dlharmon I general, I cheat by not trying to use coax above 24 GHz, but I really should give it a go at 47 GHz one day. I'm thinking in terms of using spatial combiners though, all in waveguide, right from the device outputs. The detailed engineering needed to get excellent matches across coax to CPWG or microstrip is Officially Hard.

@DosFox IBNUs (Important but not urgent) are things that will never get done. I'm on an endless interrupt cycle with important tasks from five years ago still in the push stack awaiting processing. New tasks are arriving faster than I can stack them. Emails about emails about emails about stuff folks are waiting for keep arriving. I'm getting fined large sums for late tax returns. I just looked at a job from 2009 that I haven't completed. Still needs doing. And yes, it's important.

Hi folks, I've just posted an edited version of one of the presentations I gave remotely at Microwave Update 2024 Vancouver. It's about some of the techniques I've been experimenting with for manufacturing antennas and feeds now I have a tame 5000-pound killer robot in my workshop, otherwise known as a SYIL X5 CNC mill.
https://youtu.be/ZDQyhEpxXmA
#radio #cnc #machining #microwave #mmWave

@vk6flab I use OpenEMS mostly as my EM Solver, but I'm also using some free optical design tools and running stuff in MATLAB and, hilariously, in Excel. For CAD and manufacturing, I'm using Autodesk Fusion to generate the G-code and machine control codes

Oh my good gracious. Lawks amercy. Gosh all hemlock and stap me vitals! Who would ever have thought that anyone would want to watch me spouting nonsense and waving my arms about on the Chube. The World has gone entirely bonkers. Only two to go and I'll be half way to getting a cheap-looking plaque. One and a half cheers!

@jmorris @M0YNG There's a competitive streak in some folks that means they just HAVE to be the loudest and the first to get a contact with $rare_entity. If they get a -18 report from the other station, then that power level is entirely justifiable, but if they are a lot louder than that, then it's a bit embarrassing, showing off for effect, "Look how loud I am". Yeah, slightly ewwww, like those folks who drive supercars in town. Hubris on steroids. Yuck.

@jmorris @M0YNG Trying to work the USA in full daylight, several hours after UK sunrise on 160 metres might need full-fat QRO, as might trying to work Alaska during a large aurora. I'm not one of the committed hair-shirt QRP brigade, despite being introduced to ham radio by the late George Dobbs, G3RJV, who was a visiting reverend at my secondary school. I just enjoy using efficient radios that are the right size for the particular application. Microwatts to kilowatt as appropriate

@M0YNG FT8 start/stop envelope shaping and the Gaussian slides between tones have all but eliminated the old switching transient wideband splats, but I find it extraordinary that ops still don't have a clue about how to set levels. It ain't rocket science. Turn off any audio gain control, compression or processing. Cut any ALC connection to amplifiers. Switch it off. Disable it. Woteva. Monitor your TX power. Turn the FT8 power slider in WSJT-X down very low. Next, (1/3)

@M0YNG ...turn the power slider up until you reach the output level you want to achieve. Make sure that if you back off by 3dB that the PA output drops 2-3dB. If not, get a bigger PA or use less power. 1dB compression isn't going to ruin the inter-tone slides.

Make sure you have Fake-It or real split working enabled so you never transmit tones that are less than 1500 Hz, so even if your TX audio chain is truly terrible, you won't transmit in-band audio harmonics.

@M0YNG If your radio can't even support Fake-it, then either never operate with a tone less than 1500 Hz or get a radio that can do split or Fake-it. Make sure your radio has linear phase response to at least the maximum tone you intend transmitting, and that the amplitude response doesn't fall off a cliff anywhere, so you get imbalances between tones.

@M0YNG It's very basic stuff, but I still see folks who don't have a clue why they are sending multiple copies of their FT8 tones at 2/3/4 times the correct spacing because they haven't enabled split or fake and they are transmitting ludicrously high levels into a terrible audio transmit chain at less than half the audio bandwidth. I also see start-up splats where some n00b is using ALC to set the transmit level, when there's a flippin slider on the actual WSJT-X page to set the level. Sheesh.

First attempt at a carbon-fibre-filled PLA support arm (one of a pair) for the milled-from-plate offset parabolic 122/134/248 GHz mmWave antenna dish. The left end attaches either side of a block bolted to the threaded holes behind the dish. The face is inclined at 18.9 degrees so points at the horizon with the bottom edge horizontal. The four mounting holes at the right end bolt to the enclosure containing the radar chip, focus rail, control electronics and feedhorn. Bit of Voronoi for bling.

This is roughly how the arms are used, but with the dish inclined at 18.9 degrees to the vertical rather than pointing at the zenith. Dish is 230 x 250 mm, made from 3/4 inch aluminium plate. The heaxagonal pockets are milled out to save weight but retain stiffness. The dish surface is accurate to about 20 micrometres, with 4 micrometre ridges from the spiral machining using an 8mm ball-ended carbide mill at 11500 rpm and 2800 mm/min on my SYIL X5 CNC mill #hamradio

Mysterious Things appearing on my Bambu X1C. Spiders to support hyperbolic Cassegrain subreflectors in the very deep Edmund Optics 18 inch parabolic dishes with f/d 0.25, so the focal point is at the same height as the dish rim. Total pain to illuminate unless you set it up as a Cassegrain, with the feedhorn phase centre right at the dish face centre orifice. These are for 76,122,134 and 248 GHz #hamradio

And this is what the printed Thing is for. Three carbon fibre rods flare outwards from the three sockets and go through metal sleeves to a support ring behind the dish. There's an M12x0.5 mm thread inside the hyperbolic sub for fine focus adjustment. One turn is a fifth of a wavelength at 122 GHz #hamradio

Here's one of the smaller Edmund parabolic dishes. This is the 12 inch/300 mm version. These take a 48 mm diameter Cassegrain sub, the 18 inch/450 mm versions take a 68 mm sub and the 24 inch/600 mm versions take a 98 mm sub and need rather stronger mountings, 6mm carbon fibre tube instead of 4mm pultruded CF rod. Shiny! #hamradio