Better watch out then next time you bump into a bunch of zombies, and think of firing at will, it may be a group day-trip.
What do you want.... glory, fame or fortune? Pick one. Which one requires an advanced degree to obtain it?
Many a people with glory, fame & fortune have od'ed or committed suicide. I'll settle with happiness.
For some people the pursuit of happiness (nice movie, btw) involves fortune (or so they think), for others finding out "what makes things tick", for others getting a decent job, for others having a good quality of life, for others leaving their mark/making the world a better place/whatever etc.. Then again, others may be perfectly happy working as bouncers at clubs.
Of course nothing "requires" a degree. We require air, food, water and shelter (well, and the internet 😛). It's just that you have better chances achieving some of the above with an advanced degree.
By which one gets to hook up with the glorious, famous, and/or fortunate.
From successful writers to top crime attorneys, one-hour talks with hookers or accomplished actors/actrices.
From Diego Maradonna in deep coke, to smoking goldplated-filter cigarettes with a prince of Quatar.
From small talk about the weather with the CEO of Venezuela's national oil company, or billion dollar "crude" oil Texans with Bentley/day creditcards.
Or attempting to convince the No1 president of Daimler Benz that it's not opportune to order half a dozen callgirls
(by pouring him and his DB mates a glass of whisky).
Best ever chat I had lasted a couple of hours, with the public relations CEO of Nike, amazing individual.
(I've got money in the bank, of an advanced shoe sole patent, from Nike. My g/f's doing, not mine)
Pays well too.
Plus grand tips, plus gratuity for every taxi ride, nightclub or casino transfer, hooker stop-over, joint or coke ride.
Plus pays university tuition (at expense of a couple of added scars and tissue).
Two advanced degrees for the ticket of one.
(afraid I'm just a private boys boarding school bloke, served hard time with the priestly brothers at a catholico jail, they invited the antichrist in. Dennenstraat 10 in Siltech city, same joint as this guy : http://nl.wikipedia.org/wiki/Charl_Schwietert )
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One of my best pals is a bouncer.
As you probably know there are some less... interesting and/or fun parts on the job description (there is an abundance of red-necks with guns here), but it's generally OK and it pays well.
By the way, having (relevantly) advanced education and being fairly well brought up (his upper-class family consists mainly of doctors and high school teachers), he easily stands out from his peers (i.e. the average brute) and, more or less, manages two clubs now.
We're way off topic, though. Let's not turn this interesting topic into another Blowtorch thread! 😛
Top turns Bottom (by the flick of a light switch, as your pal knows)
Merely a stimulant to strive for modesty, no guarantee for increased social adaptedness.
But easily makes one wind up at the wrong thread adress.
Merely a stimulant to strive for modesty, no guarantee for increased social adaptedness.
But easily makes one wind up at the wrong thread adress.
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Damir, my bad.
It's fairly easy to make multi-layer boards yourself, by glueing regular ones together, btw.
(pcb rivets and vias with solder slots)
It's fairly easy to make multi-layer boards yourself, by glueing regular ones together, btw.
(pcb rivets and vias with solder slots)
Folks, just a brief interruption from the regular scheduled program: Here's a 10-BJT single-ended variant of a JLH gain-block design posted earlier on this thread or elsewhere on this forum.
The JLH was FET-input, symmetrical and had a cascoded VAS. I have added the PNP buffer (aka Blameless/JE990), and retained the LTP current-mirror. The new trick is a matched differential current source for the LTP and the VAS, with a 1:1 current ratio between the LTP (combined legs) and the VAS.
Various other circuit elaborations are possible - cascoded VAS, cascoded JFET LTP, etc., but the minimal circuit shown above simulates pretty well as-is. It appears to work OK at fairly low rails as well as low bias currents in the gain block - down to 200 uA and below.
Edit: Added missing attachments. THD20 FFT shown is for 4V output amplitude into 600R - about -105 dBr, mostly H2 with the Class-A biased output stage shown.
The JLH was FET-input, symmetrical and had a cascoded VAS. I have added the PNP buffer (aka Blameless/JE990), and retained the LTP current-mirror. The new trick is a matched differential current source for the LTP and the VAS, with a 1:1 current ratio between the LTP (combined legs) and the VAS.
Various other circuit elaborations are possible - cascoded VAS, cascoded JFET LTP, etc., but the minimal circuit shown above simulates pretty well as-is. It appears to work OK at fairly low rails as well as low bias currents in the gain block - down to 200 uA and below.
Edit: Added missing attachments. THD20 FFT shown is for 4V output amplitude into 600R - about -105 dBr, mostly H2 with the Class-A biased output stage shown.
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Do you have a circuit that will be -140 THD+N ? Or greater than -130?
Need it for an ultra low distortion signal generator.
Thx-RNMarsh
Need it for an ultra low distortion signal generator.
Thx-RNMarsh
A modded FET990 can get to the region of -130 dBr with some or all of the following mods:
1) Separate LTP and VAS CCSes.
2) JFET Cascoded LTP CCS.
3) Wilson CM for the LTP.
4) Cherry compensation.
5) Class-A biased output stage.
6) Ultra-low noise JFETs for the LTP - InterFET 9030 or similar.
I have DIP8 FET990 that implements 1, 2, 4 and optionally 5 in the works. It's all-SMD though, so that limits the choice of LTP JFETs to the BF862, 2sk209 and a few Sanyo/ON Semi low-noise devices.
Edit: I forgot the most important mod:
7) Omit the VAS anti-latching diode or use an ultra-low leakage diode like a BAV199.
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Whomever wants to answer a question from a newbie of circuit design, what is the purpose of the series diodes in the circuit D4 and D5 going to the rail. Why do you need two diodes there, what is happening that makes that a requirement?
Just a voltage reference of about 1.2 V. One could use an LED or a low-noise band-gap reference of 1.25V if noise is a concern. Two diodes are needed to ensure that the Vbe drop of Q3 and Q6 are exceeded.
If avail to others, I'll try it and also what about the SW-OPA design.... if they ever stop fooling around with smd and pcb and the like... and finally get one built and tested.... need to see actual results as opposed to SIM only. Looking to push things 5-10dB better.
-RNM
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The circuit I posted at #2060 should do this. The attached curve is distortion @ 20kHz 10Vp into 600R. About -104dB for 2nd.
The gain is 40dB. This is in fact similar to the "distortion magnification" method that the uber makers use to get numbers for their uber OPAs. So I expect 2nd to be less than -140dB at unity gain. eg fig2 LME49710 datasheet
Of course, at these levels, decoupling, layout, earthing & other factors have as much, if not more, influence on THD. eg C5, which ostensibly is to reduce +ve PSR will also reduce THD in real life .. even with supa dupa power rails.
I pontificate further at
I don't think you will gain anything with 1) 2) 3) or 6)
My Q9 makes it easy to select output bias current. The sim is for 7mA so Class B for 10Vp 600R
But you can't do 7) Omitting your D6 gives really nasty overload. BAV199 won't do much to help. It's not leakage but modulation of the junction capacitance that introduces the distortion. Unfortunately, ANY diode in that position will give THD only about that of the original 990. 🙁
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