In the last week, I've been burned 6 times, shocked once, punctured (with blood) twice, and had to eat a single burger for three lunches in a row. And we are out of ice cream sandwiches.
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John Larkin Highland Technology, Inc
Science teaches us to doubt.
I have to sort and inventory over 700 reels of SMD components that I picked up, surplus. That will likely lead to a lot of paper cuts. Most are capac itors, from 0.3 pF to 6800 pF. I am waiting on a bundle of 7"x7"x10" boxes that were supposed to have arrived over a week ago. I can put 18 to 20 reel s in each box. I already had over 600 reels of components, most of which ar e full.
Ice cream is not on my diet, unless it is sugar free and that is hard to fi nd, since Hurricane Irma.
The ice cream sandwich shortage is at least as bad. You can apply one directly to a burn, or eat it, and either way you feel better.
I'm tuning the tempco of my Colpitts oscillator, which is tucked into the corner of a tallish enclosure, so it's really hard to replace 0603 parts; many Metcal burns. Through a modest amount of genius and a lot of experimenting and dumb luck, I've got the f/t curve parabolic with the flat at 40c, and maybe 35 ppm p-p over my operating range. I can tolerate +-500 before my PLL breaks.
Spice only helped a little. As Mike E says, the real value of Spice isn't to prove anything, it's to train your instincts.
Part of the compensation is, basically, an FR4 capacitor, which has a strong positive cap TC. The issue will be, can I get this sort of tempco in production?
I want very constant sine wave amplitude, beginning with the first oscillation cycle. Holding that amplitude turned out to be tricky and of course tangled with the tempco issue.
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John Larkin Highland Technology, Inc
Science teaches us to doubt.
Well, it was gigantic so I cut it in thirds when I got it. Some
20-something would have et the whole thing. We actually got it in a sit-down restaurant, where sit-down is a table under a tent on the sidewalk.
They also had superb beignets with a white chocolate dipping sauce. One side effect of Hurricane Katrina was a diaspora of New Orleans chefs all over the country, people who never imagined leaving but who won't now go back. The cajun/creole effect is very visible. And tasty.
We need a modest disaster in Virginia to spread out some good BBQ folks.
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John Larkin Highland Technology, Inc
Science teaches us to doubt.
Nine bucks, yikes! Oh well, goes like ammo I guess. A poster in the brew NG pointed out another place but I found that their BE-256 yeast was quite old.
Somehow production of this stuff must have stopped.
In production an FR4 cap can get iffy. How about a little local heat inside a regulator loop that keeps the temperature well above max expected but constant? The heater could be a 1206 resistor.
That's interesting. The uP knows the board temp, so it could PWM a resistor or so in the oscillator region, probably on the back side of the board. I'll include that on the next PCB rev.
We already tweak the fan speed to try to keep the overall PCB temperature constant, which will help a lot. That will help other circuits on the board too. The box will self-heat about 35C or so, with the fan off.
The fan algorithm is simple: 10 times a second, if the temp is below
40c, jog the fan voltage down. If above 40c, jog it up. The jogs are small and it powers up slow, so there is no acoustic drama.
formatting link
There are varicaps and things too. Everything affects the tempco. I can tune C4 to zap the 1st order term.
Worst case, every batch of PCBs could have a different value of C4. Production would *not* like that.
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John Larkin Highland Technology, Inc
Science teaches us to doubt.
Quick bit of first-aid for soldering iron burns: Keep a few fast-food ketchup packs in a nearby freezer. (They don't freeze solid). When you burn yourself, _quickly_ fetch a ketchup pack from the f reezer and hold it on the burn until it runs out of cold -- several minutes . It's the right amount of cold for the right amount of time, and the squi shy pack makes good contact with the burn. Don't knock it till you've trie d it.
Most of the burns are little swipes off the side of a Metcal tip, very hot but small. Just did another one.
Sometimes I'm holding a bus wire or a resistor lead in place while it's being soldered, and I notice it's burning my finger. Best to endure the pain and get the joint right. Fingers eventually fix themselves.
Quote "Ihr Shop wurde installiert. Lesen Sie in unserem Guide mehr zu ersten Schritten mit JTL-Shop, der Grundkonfiguration und dem erstem Abgleich mit JTL-Wawi".
Ahm ...
Anyhow, there are also a few shops in the US that still have some but it's quite old, expiration date is too close. Yeast viability is a big thing with brewers and especially so when brewing a Belgian abbaye ale.
Sure you can and I do that to some extent. I harvest yeast from previous batches. For example, because of BE-256 being expensive and now almost unobtanium I stagger my Belgian beers. A Paterbier is mild and takes one pouch. Then I siphon off trub but for more 2x the initial number of yeast cells. Then I brew a Tripel or Quadrupel which needs a high dose of yeast. Later I siphon that and make a Porter with it. The rest of the trub doesn't go to waste either because we bake bread with it.
However, so far I've never dared to go past 4th generation with yeast. Mutations can result in off-flavors or worst case a ruined batch. Considering that 4-5h of work go into each batch that would not be cool.
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