Re: TCLE

From	"Edward Rawde" <invalid@invalid.invalid>
Newsgroups	sci.electronics.design
Subject	Re: TCLE
Date	2026-05-05 15:30 -0400
Organization	BWH Usenet Archive (https://usenet.blueworldhosting.com)
Message-ID	<10tdgh2$1okg$1@nnrp.usenet.blueworldhosting.com> (permalink)
References	(8 earlier) <10tcheg$bniu$1@dont-email.me> <10tct29$qfl$1@nnrp.usenet.blueworldhosting.com> <10td5v2$hs7g$2@dont-email.me> <10td6tq$16h3$1@nnrp.usenet.blueworldhosting.com> <10tddr8$krhq$1@dont-email.me>

Show all headers | View raw

"piglet" <erichpwagner@hotmail.com> wrote in message news:10tddr8$krhq$1@dont-email.me...
> On 05/05/2026 5:46 pm, Edward Rawde wrote:
>> "Bill Sloman" <bill.sloman@ieee.org> wrote in message news:10td5v2$hs7g$2@dont-email.me...
>>> On 5/05/2026 11:58 pm, Edward Rawde wrote:
>>>> "Jeroen Belleman" <jeroen@nospam.please> wrote in message news:10tcheg$bniu$1@dont-email.me...
>>>>> On 5/5/26 09:29, Bill Sloman wrote:
>>>>>> On 5/05/2026 5:08 am, john larkin wrote:
>>>>>>> On Tue, 5 May 2026 03:13:24 +1000, Bill Sloman <bill.sloman@ieee.org>
>>>>>>> wrote:
>>>>>>>
>>>>>>>> On 4/05/2026 9:19 pm, john larkin wrote:
>>>>>>>>> On Mon, 4 May 2026 17:06:00 +1000, Bill Sloman <bill.sloman@ieee.org>
>>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>>> On 4/05/2026 3:05 am, john larkin wrote:
>>>>>>>>>>> On Mon, 4 May 2026 01:19:48 +1000, Bill Sloman <bill.sloman@ieee.org>
>>>>>>>>>>> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> On 4/05/2026 12:09 am, john larkin wrote:
>>>
>>> <snip>
>>>
>>>> Bill couldn't get below 60dB with over 60 components.
>>>> The circuit below is comfortably 100dB in simulation with only 18
>>>> components.
>>>
>>
>> The earliest description I can find for that oscillator (which is the same one JM used) in filter form
>> rather than oscillator form which requires one more resistor is
>> https://www.worldradiohistory.com/UK/Wireless-World/70s/Wireless-World-1978-09.pdf
>> Page 58 (pdf page 60)
>> Can anyone trace it back further?
>>
>>
>> <snipped nonsense>
>>
>>
>
> Isn't that basically a state-variable filter topology?

Yes

> I am sure goes back earlier than 1978 - I recall seeing it in the 1972 Natsemi LM3900 app note and even then it was not a new 
> topology, I think it was well known in 1960s if not earlier?

I was curious about its origins.
The term Bi-Quad also seems to be used.
See fig 40
https://www.ti.com/lit/pdf/snoa653


>
> piglet
>

Back to sci.electronics.design | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

TCLE john larkin <jl@glen--canyon.com> - 2026-05-03 07:09 -0700
  Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-04 01:19 +1000
    Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-03 10:05 -0700
      Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-04 17:06 +1000
        Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-04 04:19 -0700
          Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-05 03:13 +1000
            Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-04 12:08 -0700
              Re: TCLE Jan Panteltje <alien@comet.invalid> - 2026-05-05 06:54 +0000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-05 07:34 -0700
                Re: TCLE Jan Panteltje <alien@comet.invalid> - 2026-05-05 16:57 +0000
              Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-05 17:29 +1000
                Re: TCLE Jeroen Belleman <jeroen@nospam.please> - 2026-05-05 12:40 +0200
                Re: TCLE "Edward Rawde" <invalid@invalid.invalid> - 2026-05-05 09:58 -0400
                Re: TCLE "Edward Rawde" <invalid@invalid.invalid> - 2026-05-05 10:09 -0400
                Re: TCLE "Edward Rawde" <invalid@invalid.invalid> - 2026-05-05 10:10 -0400
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-06 02:30 +1000
                Re: TCLE "Edward Rawde" <invalid@invalid.invalid> - 2026-05-05 12:46 -0400
                Re: TCLE piglet <erichpwagner@hotmail.com> - 2026-05-05 19:44 +0100
                Re: TCLE "Edward Rawde" <invalid@invalid.invalid> - 2026-05-05 15:30 -0400
                Re: TCLE Jeroen Belleman <jeroen@nospam.please> - 2026-05-05 18:37 +0200
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-06 02:15 +1000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-05 07:41 -0700
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-06 02:38 +1000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-05 11:52 -0700
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-08 04:25 +1000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-07 13:14 -0700
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-08 15:03 +1000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-08 03:26 -0700
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-08 22:26 +1000
  Re: TCLE Lasse Langwadt <llc@fonz.dk> - 2026-05-03 19:12 +0200
    Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-03 12:01 -0700
      Re: TCLE Lasse Langwadt <llc@fonz.dk> - 2026-05-04 23:30 +0200
        Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-04 15:06 -0700
          Re: TCLE Lasse Langwadt <llc@fonz.dk> - 2026-05-05 00:50 +0200
            Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-04 15:58 -0700
              Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-05 17:36 +1000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-05 11:48 -0700
                Re: TCLE Bill Sloman <bill.sloman@ieee.org> - 2026-05-06 18:45 +1000
                Re: TCLE Lasse Langwadt <llc@fonz.dk> - 2026-05-05 22:55 +0200
              Re: TCLE someone <2a59d59e3809f827ce709d3815e3950eef4a6a93af5557a93a7fdfba71460843@example.com> - 2026-05-05 18:15 +0000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-05 11:38 -0700
                Re: TCLE Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2026-05-05 19:25 +0000
                Re: TCLE john larkin <jl@glen--canyon.com> - 2026-05-05 13:41 -0700
                Re: TCLE Lasse Langwadt <llc@fonz.dk> - 2026-05-06 00:05 +0200
                Re: TCLE Gerhard Hoffmann <dk4xp@arcor.de> - 2026-05-05 21:09 +0200
  Re: TCLE "Edward Rawde" <invalid@invalid.invalid> - 2026-05-03 15:49 -0400

csiph-web