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RIP to Bruce Loose, vocalist for the band Flipper. Haven’t listened to them in a long time, but will pull out Generic Flipper and raise a glass…. https://www.nme.com/news/music/flipper-singer-bassist-bruce-loose-dies-aged-66-3890561

E-bike is gonna be it for me. Who am I kidding? I’m like the bare minimum of cardio fitness to do these rides and these are the easiest 25 miles will ever be because flat farm roads. I did 50+ miles on the Diverge and I feel confident this is the right choice. I will say, I am not sure people are on about with these 1x front chain rings. Nice to have a bunch of climbing gears but I never felt like I had exactly the gear I wanted for the public roads. I'm certainly fit enough to ride a road bike around on these farm roads but I get the feel that if I go back to Marin the constant up-and-down will end me. Going faster than my power output would otherwise allow also has some appeal.

I was going to ask who the tiny old guy was.. got it.. Nice attitude shot of Esmé as always.

I’m looking for a way to produce 125 VDC low current. One idea is to use a switching voltage regulator, LT8365 maybe … board size 2.0in x .73in (51mm x 18mm)

Thank you, Shawn. Good to know how Megatron XL behaves.

Alright, here are the quick results. Case 1: Rupper = 1500, Rlower = 3200, G-pot = 10 kΩ (set at ~10%). Va ≈ –1.7 V, Vgk ≈ –85.6 V, Plate Voltage = 362.2 V. Case 2: Rupper = 1200, Rlower = 2600, G-pot = 10 kΩ (set at ~10%). Va ≈ 3.3 V, Vgk ≈ –85.3 V, Plate Voltage = 367.4 V. I didn’t measure at 38 mA, since I wasn’t sure whether the EL34 would be overloaded, and I also don’t have the right resistor configuration at hand (Vishay Dale parts are really not cheap). That said, you can see that in both cases the plate voltage stays in the 400 V max cell, which in theory should not be dangerous, but who really knows.

That depends entirely on which wood is being worked.

Nipple, or otherwise?

Woodworker: An official title that one earns from buying clamps.

Yikes. Beastly!

The Mavericks are annoying. The crocs are truly epic.

A couple of pies for dinner with friends from across the street. One with Mexican chorizo, red onion, corn and jalapeño, over cheddar, mozzarella and topped with grated cotija, which was the clear winner. The other with pepperoni, shaved fennel, mushrooms, and fresh basil grown by the neighbors over mozzarella, which was tasty but more basic. Working with a shitty oven and a pizza stone instead of a pizza steel was a handicap, but it worked out fine.

After the air disaster article linked in the reading thread where Rear Admiral Moffett doesn’t exactly come off well, decided to return today with Esmé to the Moffett Field Museum that’s five minutes from our house. Of course the museum is about the place, not the man the place is named after, and the emphasis is on the USS Macon, once docked here, not its sister ship the USS Akron, where Moffett and nearly the entire crew perished (twice those of Hindenburg), all in the pursuit of military rigid airship supremacy (20/20 of course on what was accomplished there), but sometimes strange how heroes are selected. Bonus: Tom Cruises. Still a great, volunteer-led tiny museum

With temps in the high 50s and storms rolling through after mile 30 we decided that bit over 70 miles was the smart play. Despite 2-1/2hrs in heavy rain still was a great event for an even better cause.

Tungsten heatsink Very exclusive

It turned out to be the four big caps had failed. I took it to a local hi-fi dealer who recently started carrying Stax and had it repaired.

I had some fun on my first longer ride (22mi) but I haven’t felt so exposed cardio-wise in a long time. I think I’m on a bike one size too big so I’m going to try and see if the shop can swap me for a smaller one for tomorrow. My hands and shoulders are a little sore from having to stretch a little further than is comfortable to reach the hoods and drops. Very much leaning towards an e-bike so the assist will be there if i want it, but I’m going to try another 20-ish mile ride tomorrow and see how I feel. https://strava.app.link/G4g98I3TrWb

RIP to a hockey legend, Ken Dryden. Even as a Boston Bruins fan and forever-enemy of the Montreal Canadiens, he was something special. And fuck fuck fuck cancer! https://www.cbc.ca/sports/hockey/nhl/ken-dryden-obit-1.7627028

Please do. Silk screen says +/-450V, I think. I got this table based on LTspice simulation for supply voltage +/-450V. Rupper is upper tube cathode resistor, Rlower is lower tube cathode resistor, values give offset zero for given Rupper , the resistance is the total of paralleling resistors.

Have a good ride Nate!

Godspeed!

Tomorrow is the day. Weather isn't looking great but we'll get it done regardless. Thanks again for all the support. #NFLO

Cervelo, without thinking. My gen Roubaix can't run wide enough tires, the newer ones can.

After some rounds of trial and simulation, I thought I’d put together a rough guide for setting the 300B operating point, mainly to make life easier when dialing things in. Given static operating currents: 34.3 mA → Rk = 2160 Ω, Vgk = –73.7 V, Grid pot = 10 kΩ, set around 10%. 23.8 mA → Rk = 3200 Ω, Vgk = –75.8 V, Grid pot = 10 kΩ, set around 10%. Plate voltage check (with Va = 0 V target): At 34.3 mA → Plate Voltage = Va – Vk = 0 – (–325.9) = 325.9 V. At 23.8 mA → Plate Voltage = 323.8 V. By matching these points against the 300B characteristic curves (see the red-line markers in the attached graph), the theoretical Vgk comes out roughly between –70 V and –75 V, which lines up with the measured –73.7 V and –75.8 V. From the curves, the 34.3 mA point looks more linear. Pushing current further could be even better, but that depends on whether the EL34 can handle it safely and whether the PSU has enough overhead. All of these measurements are under a ±400 V supply. The 300B datasheet gives a max plate voltage of 400 V (though some manufacturers claim 450 V). On the XL build, with 400 V rails, the plate voltage is about 335 V, and still within a safe zone. I haven’t confirmed the behavior at 450 V rails, but I’d expect plate voltage around ~380 V, which starts to get a bit risky. If anyone’s interested, I can run tests at 450 V and report back the voltages at each node.