Everything posted by luvdunhill
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Group Build: Dynafet
no, good matches are very hard to get between the devices 2SA1145/2SC2705. I in fact have nearly perfect matches, the front end, and even the MOSFETs. In general, low hfe devices are more consistant. For example, try matching the 2SA1349/2SC3381, it's very hard. That's why I used single devices... and then matched a crap load of them. This is neither here or there though, the circuit shouldn't really care that much about this anyways...
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What are you drinking now, pt 2.
Making some orgeat
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And now what did you do TODAY?
I did graduate work at Columbia and rather enjoyed it. It was in Computer Science though.
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Group Build: Dynafet
I constructed both CCSes on a breadboard and chose a resistance that resulted in 2mA current draw. I'll use the same devices on the actual board. I'll do this for the other CCSes as well. Looks like I'm lacking one resistance (figures). I'm going to have to take stock of what I have and make one order to shore things up.
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Group Build: Dynafet
well, for what it's worth (I just measured this), with a Vf of 1.838V I get 595 ohms for the top (R21) and 560 ohms for the bottom (R22) to draw 2.000mA through the front end. Hfe of both polarity (yeah I know obsessive) is 136 and the Mouser part for the LEDs are 859-LTL-4213. So, perhaps turn it up a bit.
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Group Build: Dynafet
Also, Vbe of the transistors in the DynaFET are .1V or so higher than those in the other Dyna- designs, IIRC. Yes, that's the man!
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Group Build: Dynafet
500 ohms assumes a 1.6V LED, which results in 2mA for each half of the front end (1mA per FET). I plan on choosing LEDs an adjusting this value to result in the final 2mA. Seems easier to me. I don't have any EAGLE files. I'd recommend PMing Dan C and see what he can do to help.
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Group Build: Dynafet
what is R55 again? I'm getting closer to getting a new board stuffed. If you don't mind, what equivalent resistance do you have across R22 || TR2 and R21 || TR1? I'd like to put a fixed resistor there and was thinking 560 ohms (assuming that the design point was at the center of the pot).
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Group Build: Dynafet
Still cannot use this new website, none of these posts showed up new for me. Can you drive more current through the output stage? I'd guess this to be the problem. I'll be caught up with you in a few days and we can compare notes. Stuffing basic stuff tonite hopefully.
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Stax - foam or cloth?
It's not hard really. High PSRR.
- Cookware Thread
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The ultimate DIY? A Stax SRM-T2!
you can feel it though what's a few extra watts though?
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Group Build: Dynafet
Nice! The lower gain just needs more compensation. I tested it down to 3 I believe. I'd definitely try both feedback points, it's worth it.
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What are you drinking now, pt 2.
All those Kirsch drinks were nice. The layering with the sweet vermouth and Kirsch was especially nice.
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What are you drinking now, pt 2.
That would be "The Rose"
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What are you drinking now, pt 2.
I was just about to recommend this one. That recipe exactly too.
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What are you drinking now, pt 2.
Margarita Equal parts
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What are you drinking now, pt 2.
2 oz dry vermouth 1 oz kirschwasser 1 tsp raspberry syrup Shake and strain into a cocktail glass and garnish with a cherry.
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What are you drinking now, pt 2.
Following Jim's lead.. Blackthorn Cocktail 2 oz gin 0.75 oz Dubonnet Rouge (0.5 oz Carpano) 0.75 oz kirschwasser Stir.
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Does lossless audio guarantee good sound?
Yet another link that doesn't work with Tapatalk around here (the first one) (grumbles)
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What are you drinking now, pt 2.
That's about right. Totally hit the spot tonite. Nice to be back in the sling of things
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What are you drinking now, pt 2.
Thanks kind sir!
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What are you drinking now, pt 2.
The Straits Sling 2 oz gin 0.5 oz kirschwasser 0.5 oz Benedictine Juice of 1/2 lemon 1/4 tsp orange bitters 1/4 tsp Angostura bitters Soda water Shake everyone on ice (except the soda) and strain into a sour glass. Add soda. Add fruit.
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And now what did you do TODAY?
http://www.eweek.com/c/a/Security/Shmoocon-and-the-Shmoo-Ball/
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The ultimate DIY? A Stax SRM-T2!
dare I ask what sort of specs a scope must have to reliably track this down?