It could be described as a program that optimises our genes' ability to continue though the generations. We ourselves are just big lumbering machines built by our genes to reproduce themselves. Only the blueprints matter, and they compete on a long time scale. We're only important secondarily.
A wonderfully readable and original (although he modestly denies originality) discussion is Richard Dawkins' _The Selfish Gene_. Ignore the terrible title; it's not about the obvious inference at all. Also has good discussion of game theory and a layman's (that's me!) intro to genetics.
Much thanks, as always,
Chris
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I can see the logic of that, at least historically. But what happens when we learn how to re-program genetics, eventually dynamically, with computer guidance. Their will no longer be the need for genetic selection in the usual sense. The need for a biological framework might altogether disappear even, synthetic intelligence making its appearance. Not to mention population overload, the real cause of climate warming and just about every other problem. Some kind of phase transition must occur at some point.
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I worked the evening shift and had a Hobie Cat for about 15 years. I hit Ft. Lauderdale beach at about 9:30 AM and stayed until about 2 PM almost every weekday from 1978 till the early 90's. Back then sunscreen use was not common.
I have been taking some form of Niacin, currently Niacinamide for years due to a hereditary disposition for high cholesterol and ridiculously high triglycerides (over 1000) without medication.
I never bought into the cholesterol = atherosclerosis hype (even the drug company's own data shows that 50% of heart attacks happen in people with good numbers). There is now enough real data to show that high triglycerides, low "good" cholesterol, and high blood sugar in combination show the best correlation with heart attacks.
I have all 3 and have failed 2 stress tests. I keep up with young people in extended strenuous outdoor activities without any heart related symptoms, yet I have been known to turn blue after some mild exercise. $35K worth of testing, including a cardiac catheterization failed to find anything wrong.
There are a couple of topical chemotherapies that can kill a basal cell carcinoma, squamous cell carcinoma (what I get) and even an early stage melanoma, but they are expensive (Zyclara is $600 for 7 grams) and insurance doesn't cover them.
When we begin to trust the results of machine "intelligence" without stopping to think if the results are realistic or even believable, then we get into real trouble. I have seen this at work from those who "calculate and simulate" but have never actually built anything.
I had an argument with a well respected member of the technical staff over a proposed two way radio design, that turned into a month long debate that I lost. I had told him that his radio design would not work in certain environments, explained why, and offered to take him to a test site with a spectrum analyzer. We built his prototype, and it passed all the qualification testing and was headed toward product acceptance when I convinced a couple of boss types to go with me to a Miami Dolphins NFL game, and bring some prototype radios. The stadium is next to the antenna farm for all the Miami TV stations with a combined ERP of about 10 MEGAWATTS on frequencies very close to the radios operational frequency.
Somehow the last part of my post never made it to the forum, Windows 10 laptop.
The design was for a cost reduced two way radio product using superhetrodyne (called superhet) technology which has been used since the 1920's. The radio was designed to receive and transmit (with 4 watts) on any of several programmed frequencies from 380 to 520 MHz. Previous products broke this 140 MHz range into smaller ranges, or used separate receiver front ends for 40 MHz or so chunks of spectrum.
UHF TV broadcasting in the USA covers 470 to 698 MHz. EACH TV station can radiate a maximum of 1 MW of ERP (Effective Radiated Power). Most major cities now put all of their TV broadcasting systems at the same site, or close together. This is so that consumers do not need multiple antennas pointed in different directions.
Every superhetrodyne radio receiver converts the incoming radio signal range to a single Intermediate Frequency (IF) for amplification, using a mixer stage and a local oscillator (LO). The mixer will combine two signals to create two new signals at the sum and difference frequencies. A typical superhet radio uses the difference frequency as the IF.
Example: 45 MHz is a common IF frequency for a UHF radio and was used in this design. Lets say the radio was set to receive 450 MHz. The internal LO would be programmed to 495 MHz, which would mix with 450 MHz to create 45 MHz. (495 - 450 = 45)
All superhet radios will also respond to an unwanted frequency, known as the IMAGE frequency. In this case 540 MHz will also be received (540 - 495 = 45).
The radio must have one or more (usually 2) filters between the antenna and the mixer to reject this image frequency. This is a known design challenge for superhet radio designers, and it's really quite a bit more complicated since all the frequencies and their harmonics must be considered because the mixer is a nonlinear device by design. Complex spreadsheets or computer simulations are used to pick IF and LO frequencies.
It is well known that the IF frequency must be chosen such that strong outside signals will not get into the radio directly into the IF amplifier.
It is was not so common to think about the signals present in the air on the image frequency, only the rejection spec. There were 3 times in my career I saw Motorola get burned big time for failing to consider just how powerful a 1 million watt TV transmitter, or a tower full of cellular base stations can be. It will penetrate the plastic housing and get into the mixer circuitry after the filtering, or just blast right through the filters.
In this case on the upper deck of the stadium the TV signals were so strong that the radio wouldn't receive ANYTHING at all on any frequency, but that had to do with the compromises needed to make a tunable filter capable of covering a 140 MHz bandwidth.
Several miles away from the TV towers the radios still had problems receiving base repeaters on frequencies where TV channels were on the image frequency. The design was going through some serious changes when I left the company after a 41 year career.
The design was for a cost reduced two way radio product using superhetrodyne (called superhet) technology which has been used since the 1920's. The radio was designed to receive and transmit (with 4 watts) on any of several programmed frequencies from 380 to 520 MHz. Previous products broke this 140 MHz range into smaller ranges, or used separate receiver front ends for 40 MHz or so chunks of spectrum.
UHF TV broadcasting in the USA covers 470 to 698 MHz. EACH TV station can radiate a maximum of 1 MW of ERP (Effective Radiated Power). Most major cities now put all of their TV broadcasting systems at the same site, or close together. This is so that consumers do not need multiple antennas pointed in different directions.
Every superhetrodyne radio receiver converts the incoming radio signal range to a single Intermediate Frequency (IF) for amplification, using a mixer stage and a local oscillator (LO). The mixer will combine two signals to create two new signals at the sum and difference frequencies. A typical superhet radio uses the difference frequency as the IF.
Example: 45 MHz is a common IF frequency for a UHF radio and was used in this design. Lets say the radio was set to receive 450 MHz. The internal LO would be programmed to 495 MHz, which would mix with 450 MHz to create 45 MHz. (495 - 450 = 45)
All superhet radios will also respond to an unwanted frequency, known as the IMAGE frequency. In this case 540 MHz will also be received (540 - 495 = 45).
The radio must have one or more (usually 2) filters between the antenna and the mixer to reject this image frequency. This is a known design challenge for superhet radio designers, and it's really quite a bit more complicated since all the frequencies and their harmonics must be considered because the mixer is a nonlinear device by design. Complex spreadsheets or computer simulations are used to pick IF and LO frequencies.
It is well known that the IF frequency must be chosen such that strong outside signals will not get into the radio directly into the IF amplifier.
It is was not so common to think about the signals present in the air on the image frequency, only the rejection spec. There were 3 times in my career I saw Motorola get burned big time for failing to consider just how powerful a 1 million watt TV transmitter, or a tower full of cellular base stations can be. It will penetrate the plastic housing and get into the mixer circuitry after the filtering, or just blast right through the filters.
In this case on the upper deck of the stadium the TV signals were so strong that the radio wouldn't receive ANYTHING at all on any frequency, but that had to do with the compromises needed to make a tunable filter capable of covering a 140 MHz bandwidth.
Several miles away from the TV towers the radios still had problems receiving base repeaters on frequencies where TV channels were on the image frequency. The design was going through some serious changes when I left the company after a 41 year career.
Mixer is a quad mosfet switch. This has been found to be the best way to "mix" two RF signals. The switching mixer is driven with a square wave LO and spends no time in the linear region.
The old pentagrid converter and most every mixer since then attempted to operate in the linear region with just enough nonlinearity to actually mix.
RF mixing action is very similar to IMD in an audio amp. We all know that IMD rarely occurs alone, its brother in law THD tags along for the ride. This means that there will be harmonics of the RF and LO signals in the mix.
In the audio world, we test with, but don't listen to sine waves. Music usually consists of many simultaneous tones. In many areas the radio frequency spectrum is completely full. The mixer in a two way radio must deal with hundreds of signals at the same time, and often the one you want is among the weakest. The total dynamic range of a modern audio recording is often compressed to maybe 30 db.
We spec a high tier two way radio to be capable of receiving a signal that is 80 dB weaker than the signals on the neighboring channels, 25 KHz away. The weak signal may be as low as 1/4 of a microvolt.
A mid tier radio (the one in question) specs at 65 dB and 1/2 microvolt.
The old pentagrid converter and most every mixer since then attempted to operate in the linear region with just enough nonlinearity to actually mix.
RF mixing action is very similar to IMD in an audio amp. We all know that IMD rarely occurs alone, its brother in law THD tags along for the ride. This means that there will be harmonics of the RF and LO signals in the mix.
In the audio world, we test with, but don't listen to sine waves. Music usually consists of many simultaneous tones. In many areas the radio frequency spectrum is completely full. The mixer in a two way radio must deal with hundreds of signals at the same time, and often the one you want is among the weakest. The total dynamic range of a modern audio recording is often compressed to maybe 30 db.
We spec a high tier two way radio to be capable of receiving a signal that is 80 dB weaker than the signals on the neighboring channels, 25 KHz away. The weak signal may be as low as 1/4 of a microvolt.
A mid tier radio (the one in question) specs at 65 dB and 1/2 microvolt.
I have been a radio designer for 31 of those 41 years. I built several ham radio projects over those years, and most of them have been solid state.
I made several tube based RF power amps in the 80's, but today, silicon, GaAs, GaN or SiC just work better.
I made a balanced RF preamp and a balanced RF mixer back in the 80's using 5670 tubes, and it did work very good up to 30 MHz, but today I would use mosfets, or silicon pHEMT. It would be nearly impossible to build a frequency synthesizer (PLL) using tubes.
Note:
Motorola never made their own tubes. Most are GE as is your sample, but I have seen Sylvanias, Hitachi and Raytheon.
I made several tube based RF power amps in the 80's, but today, silicon, GaAs, GaN or SiC just work better.
I made a balanced RF preamp and a balanced RF mixer back in the 80's using 5670 tubes, and it did work very good up to 30 MHz, but today I would use mosfets, or silicon pHEMT. It would be nearly impossible to build a frequency synthesizer (PLL) using tubes.
Note:
Motorola never made their own tubes. Most are GE as is your sample, but I have seen Sylvanias, Hitachi and Raytheon.
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Slightly OT, but clearly we are doing it all wrong and we can tell how a tube will sound just by looking at it. Line Magnetic Audio LM-518IA integrated amplifier Tube Rolling | Stereophile.com
Well, It's clear to me what sort of music that Smoldering-Amp guy listens to. Punk ! I mean, look at that tube, it's a skinhead. Trying to get by unnoticed with that Fess Parker hat on. We all know what a real tuber should look like . . .
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Yeah, Potato Head Bobby was a friend of mine....
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Potato-head bobby was a friend of mine
He opened three of his eyes in the food stamp line
He opened four of his eyes in the food stamp line
He opened five of his eyes in the food stamp line
He opened six of his eyes in the food stamp line
Read more: Frank Zappa - Advance Romance Lyrics | MetroLyrics
Can't have a spud without all them eyes.
Edit
Potato-head bobby was a friend of mine
He opened three of his eyes in the food stamp line
He opened four of his eyes in the food stamp line
He opened five of his eyes in the food stamp line
He opened six of his eyes in the food stamp line
Read more: Frank Zappa - Advance Romance Lyrics | MetroLyrics
Can't have a spud without all them eyes.
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