Re: Final final 1kHz oscillator

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vhue9h$243sl$1@dont-email.me...

On 24/11/2024 5:11 am, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vhs1ea$1kbt4$1@dont-email.me...

On 23/11/2024 4:12 pm, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vhrma8$1io30$2@dont-email.me...

On 23/11/2024 3:32 am, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vhp713$12bnt$2@dont-email.me...

On 21/11/2024 1:00 am, Bill Sloman wrote:

On 20/11/2024 2:03 pm, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vhjj2v$24eu4$3@dont-email.me...

On 20/11/2024 1:29 pm, Bill Sloman wrote:

On 20/11/2024 12:59 pm, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:vhibce$1t7v2$1@dont-email.me...

On 18/11/2024 2:58 pm, Edward Rawde wrote:

"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:n7iijjdeqecl0kmub0bq5in0dbm60m7qam@4ax.com...

On Thu, 14 Nov 2024 11:14:28 -0500, "Edward Rawde"
<invalid@invalid.invalid> wrote:
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"JM" <sunaecoNoChoppedPork@gmail.com> wrote in message news:t5fajjdteskfftvkf84iqsp2vc4b9ta5kj@4ax.com...

On Fri, 8 Nov 2024 15:43:41 -0500, "Edward Rawde"
<invalid@invalid.invalid> wrote:

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I found that adding a couple of 14nmH ferrite beads around the transistors and the FETs stopped the simulation dropping out
after getting stuck on a too-short time step.

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Additional components in the simulation that you could probably leave out of a real circuit. I've found another place to put a
ferrite bead which speeds up the simulation ever more, but it is till not all that quick.
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The current version isn't simulating all that fast - I let it run over-night and the amplitude control feed back loop turned
out
to have been underdamped to the point of instability - it kept on hitting the rails and overshooting back into them. The
current
version - with more damping - is now on it's second millisecond.

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Ok well when you've got a circuit which rivals the one I posted for harmonic distortion and component count let me know.

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I'm not going to be constrained by that.

Ok I'll settle for matching the harmonic distortion level, even if you need 1000 components.

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Component count isn't all that important. If you can replace an expensive or hard to get component with a couple of cheap ones,
that's a win.

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I've worked in plenty of places where using four times as many components as you could have used (and hence four times the cost)
would not be seen as a win.

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Four times the number of components isn't four times the cost, as I did point out. I got brownie points once for replacing a fifty
pence 25-turn trimming potentiometer with a more settable trimmer with the same footprint at five times the cost.
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What we lost on the cost of the part we more than won back in a half-hour drop in setting up time. The original designer should
have put in coarse and fine pots, which would have been more parts, but still cheaper than my quick and dirty fix.

Alternative ways of doing much the same job are also interesting -

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Sure. There are plenty of examples of that, such as make it a beam tetrode instead of a pentode.
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patent evasion used to be a popular sport. Once the patentable details are buried inside a programmable device it's less
worthwhile.
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Lawyers don't like going into technical detail - RCA won a colour TV patent case against EMI in a US Court because the judges
couldn't be persuaded that quadrature modulation was exactly the same thing as sine/cosine modulation.

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Sony didn't care about the PAL patents. They just put a hue control on their early sets.

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The EMI-RCA court battle preceded PAL versus NTSC. It was about how you added colour information on top of the original black and
white brightness signal.

We all know that Bill.
In any case NTSC (which uses quadrature) and PAL (which also uses quadrature along with an additional trick or two) and probably
also SECAM (which uses FM) are all history now unless you need to generate a signal locally for an existing set.

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--
Bill Sloman, Sydney
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