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Fast buffer idea

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  Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 13:50 -0400
    Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 11:27 -0700
      Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-14 19:19 +0000
        Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 15:24 -0400
        Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 12:54 -0700
          Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:02 -0400
            Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 13:10 -0700
              Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:16 -0400
                Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:18 -0400
                Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 14:14 -0700
                Re: Fast buffer idea "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-05-15 19:51 +0100
                  Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 13:17 -0700
                    Re: Fast buffer idea Clifford Heath <clifford.heath@gmail.com> - 2017-05-17 09:14 +1000
                      Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-16 16:26 -0700
                        Re: Fast buffer idea "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-05-17 02:04 -0500
          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-14 20:26 +0000
            Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:31 -0400
            Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:43 -0400
            Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 14:17 -0700
              Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-14 21:53 +0000
                Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 16:14 -0700
                  Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 19:59 -0400
                    Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 20:06 -0700
                  Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 00:16 +0000
                    Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 20:10 -0700
                      Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 03:28 +0000
                        Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 20:48 -0700
                          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 04:17 +0000
          Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 07:56 +0000
            Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 06:58 -0400
              Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 12:59 +0000
            Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-15 07:01 -0700
              Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 10:09 -0400
                Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 10:18 -0400
                  Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-15 08:56 -0700
                    Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 16:02 +0000
                      Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 10:33 -0700
                        Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 18:15 +0000
                          Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 14:25 -0400
                            Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 14:26 -0400
                  Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 16:24 +0000
                    Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 16:36 +0000
                      Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 17:18 +0000
                        Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 13:30 -0400
                          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 18:07 +0000
                            Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 19:19 +0000
                              Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 19:45 +0000
                                Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-16 08:33 +0000
                          Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 19:13 +0000
                            Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 15:33 -0400
                              Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-16 08:16 +0000
                                Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-16 22:10 -0400
                        Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 19:10 +0000
                Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-15 08:55 -0700
                  Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 12:51 -0400
                    Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 12:56 -0400
                      Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 13:05 -0400
                    Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 10:28 -0700
                      Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 13:38 -0400
                        Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 11:29 -0700
                          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 18:41 +0000
                            Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 13:19 -0700
                              Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 20:46 +0000
                                Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 13:56 -0700
                                  Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 21:00 +0000
                                    Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 16:46 -0700
                                      Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-16 01:22 +0000
                                        Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-16 11:16 -0700
                                          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-16 18:55 +0000
                                            Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-16 12:21 -0700
                                              Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-16 20:33 +0000
                                                Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-16 14:00 -0700
                                                  Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-16 21:21 +0000
                                                    Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-16 16:15 -0700
                                                      Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-16 23:58 +0000
                                                        Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-16 17:51 -0700
                                                    Re: Fast buffer idea pcdhobbs@gmail.com - 2017-05-16 16:30 -0700
                                                      Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-17 00:16 +0000
                                                        Re: Fast buffer idea pcdhobbs@gmail.com - 2017-05-16 18:05 -0700
                                                          Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-16 20:05 -0700
                                                          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-25 01:13 +0000
                                                            Re: Fast buffer idea Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-24 21:43 -0400
                                                              Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-30 03:16 +0000
                                                  Re: Fast buffer idea Ralph Barone <ralph@invalid.com> - 2017-05-17 02:26 +0000
                                                    Re: Fast buffer idea Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2017-05-17 08:34 +0200
                                                      Re: Fast buffer idea Ralph Barone <ralph@invalid.com> - 2017-05-17 14:31 +0000
                                                        Re: Fast buffer idea Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-17 10:39 -0400
                                                          Re: Fast buffer idea Reinhardt Behm <rbehm@hushmail.com> - 2017-05-17 23:02 +0800
                                          Re: Fast buffer idea Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2017-05-16 21:24 +0200
                                            Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-16 20:12 -0700
                                    Re: Fast buffer idea Winfield Hill <hill@rowland.harvard.edu> - 2017-05-25 04:38 -0700
                                      Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-25 07:28 -0700
                                        Re: Fast buffer idea "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-05-26 08:54 -0500
                                          Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-26 14:14 +0000
                                          Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-26 07:21 -0700
                                Re: Fast buffer idea "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-05-16 20:27 +0100
                          Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 15:05 -0400
                            Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 15:19 -0400
                            Re: Fast buffer idea John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-15 13:21 -0700
                              Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 20:56 +0000
                              Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 17:37 -0400
                Re: Fast buffer idea "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-05-15 19:50 +0100
                  Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 19:25 +0000
                    Re: Fast buffer idea "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-05-16 20:19 +0100
              Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 14:33 +0000
                Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 13:15 -0400
                  Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-15 19:05 +0000
                    Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-15 15:38 -0400
                      Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-16 08:12 +0000
                        Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-16 18:47 +0000
                          Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-16 21:52 -0400
                            Re: Fast buffer idea Winfield Hill <hill@rowland.harvard.edu> - 2017-05-25 05:05 -0700
                              Re: Fast buffer idea pcdhobbs@gmail.com - 2017-05-25 05:42 -0700
                                Re: Fast buffer idea Winfield Hill <hill@rowland.harvard.edu> - 2017-05-25 05:49 -0700
                                  Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-25 08:10 -0700
                              Re: Fast buffer idea Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2017-05-25 15:01 +0200
        Re: Fast buffer idea "John Miles, KE5FX" <jmiles@gmail.com> - 2017-05-14 18:53 -0700
          Re: Fast buffer idea Steve Wilson <no@spam.com> - 2017-05-15 02:45 +0000
      Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 15:23 -0400
    Re: Fast buffer idea "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-05-14 20:28 +0100
      Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:00 -0400
      Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 16:10 -0400
        Re: Fast buffer idea Winfield Hill <hill@rowland.harvard.edu> - 2017-05-14 17:58 -0700
          Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-14 23:13 -0400
          Re: Fast buffer idea Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-16 17:27 -0700
            Re: Fast buffer idea Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-16 17:34 -0700
        Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-14 20:14 -0700
          Re: Fast buffer idea "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-05-15 19:42 +0100
    Re: Fast buffer idea "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-05-16 03:29 -0500
      Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-16 06:57 -0700
        Re: Fast buffer idea bitrex <bitrex@de.lete.earthlink.net> - 2017-05-16 22:47 -0400
          Re: Fast buffer idea John Larkin <jjlarkin@highlandtechnology.com> - 2017-05-16 20:18 -0700
            Re: Fast buffer idea "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-05-17 02:22 -0500
      Re: Fast buffer idea Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-16 14:05 +0000

Page 5 of 7 — ← Prev page 1 2 3 4 [5] 6 7  Next page →

#461617

pcdhobbs@gmail.com wrote:

>>I chide Larkin on his "picosecond electronics". Do you accept his
>>claims? 
>  
> 
>>I thought not. 
> 
> You really shouldn't let your temper lead you into putting words in
> people's mouths. 
> 
> I have a few of JL's products in my lab. My favourite is the P400
> digital delay generator, which I use a fair amount--it's my go-to
> pulse generator for everything. It's similar to an SRS delay generator
> I used to have except that its jitter is a good 30 dB less (~5 ps vs
> ~200 ps). That sort of improvement doesn't happen by accident. 
> 
> You claim hundreds-of-femtoseconds jitter numbers for hard disks in
> 1970. Even if that were so, that's "sub-picosecond" and not
> "femtosecond".  
> 
> However the state of the art in hard drives in 1970 was nowhere near
> that jitter level. The 1973 IBM "Winchester" drive had a data transfer
> rate of less than 1 Mb/s. Sub-picosecond jitter? Really? Like 120-odd
> dB down? 
> 
> I seriously doubt that available test equipment could have made that
> measurement, even if by some miracle it was that good. 
> 
> How did you measure it?
> 
> Cheers
> 
> Phil Hobbs

I reviewed my old archives. It turns out I used the HP 5326 in 1971. This 
could reach 100ps using Time Interval Averaging, which was excellent for 
the time.

http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1970-04.pdf

HP released the 5370 around 1978. This could reach 20ps single shot and 
63 fs using 1e5 averaging. This took too long in production, so I settled 
on 1e4 averaging. This gave 200 fs which was 500x better than the 
original.

http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1978-08.pdf

It is clear that by the early 1980's, many people were involved in 
picosecond and femtosecond design and measurements.

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#461619

On 05/24/2017 09:13 PM, Steve Wilson wrote:
> pcdhobbs@gmail.com wrote:
>
>>> I chide Larkin on his "picosecond electronics". Do you accept his
>>> claims?
>>
>>
>>> I thought not.
>>
>> You really shouldn't let your temper lead you into putting words in
>> people's mouths.
>>
>> I have a few of JL's products in my lab. My favourite is the P400
>> digital delay generator, which I use a fair amount--it's my go-to
>> pulse generator for everything. It's similar to an SRS delay generator
>> I used to have except that its jitter is a good 30 dB less (~5 ps vs
>> ~200 ps). That sort of improvement doesn't happen by accident.
>>
>> You claim hundreds-of-femtoseconds jitter numbers for hard disks in
>> 1970. Even if that were so, that's "sub-picosecond" and not
>> "femtosecond".
>>
>> However the state of the art in hard drives in 1970 was nowhere near
>> that jitter level. The 1973 IBM "Winchester" drive had a data transfer
>> rate of less than 1 Mb/s. Sub-picosecond jitter? Really? Like 120-odd
>> dB down?
>>
>> I seriously doubt that available test equipment could have made that
>> measurement, even if by some miracle it was that good.
>>
>> How did you measure it?
>>
>> Cheers
>>
>> Phil Hobbs
>
> I reviewed my old archives. It turns out I used the HP 5326 in 1971. This
> could reach 100ps using Time Interval Averaging, which was excellent for
> the time.
>
> http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1970-04.pdf
>
> HP released the 5370 around 1978. This could reach 20ps single shot and
> 63 fs using 1e5 averaging. This took too long in production, so I settled
> on 1e4 averaging. This gave 200 fs which was 500x better than the
> original.
>
> http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1978-08.pdf
>
> It is clear that by the early 1980's, many people were involved in
> picosecond and femtosecond design and measurements.
>

Yah.  But not you, in 1970.

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

[toc] | [prev] | [next] | [standalone]

#462250

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

> On 05/24/2017 09:13 PM, Steve Wilson wrote:
>> I reviewed my old archives. It turns out I used the HP 5326 in 1971.
>> This could reach 100ps using Time Interval Averaging, which was
>> excellent for the time.

>> http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1970-04.pdf

>> HP released the 5370 around 1978. This could reach 20ps single shot
>> and 63 fs using 1e5 averaging. This took too long in production, so I
>> settled on 1e4 averaging. This gave 200 fs which was 500x better than
>> the original. 

>> http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1978-08.pdf

>> It is clear that by the early 1980's, many people were involved in
>> picosecond and femtosecond design and measurements.

> Yah.  But not you, in 1970.
 
> Cheers
 
> Phil Hobbs

I never said 1970. I said 1971. 

So I was 7 years off. Sue me.

My measurement was far more accurate than the HP 5326 could give.

And I still made millions. In 1980's dollars.

Had no clue how to handle it, and lost it all. But next time will be 
different.

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#460623

John Larkin <jjlarkin@highland_snip_technology.com> wrote:
>
> I've been doing picosecond electronics for decades, and sold a ton of
> it... more as time goes on. Sometimes things happen on the first PCB
> rev of a difficult design. We fix it. No big deal.

I've been doing picosecond stuff too.   16,666,666,666 ps, unfortunately. 

[toc] | [prev] | [next] | [standalone]

#460640

Am 17.05.2017 um 04:26 schrieb Ralph Barone:

> I've been doing picosecond stuff too.   16,666,666,666 ps, unfortunately.


Yeah, lots of them!

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#460659

Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> wrote:
> Am 17.05.2017 um 04:26 schrieb Ralph Barone:
> 
>> I've been doing picosecond stuff too.   16,666,666,666 ps, unfortunately.
> 
> 
> Yeah, lots of them!
> 

It gives me more time to think over what I'm doing :-)

I used to joke that to the relaying people anything over 60 Hz was RF, and
that to the telecom people, anything under 10.7 MHz was DC.

[toc] | [prev] | [next] | [standalone]

#460660

On 05/17/2017 10:31 AM, Ralph Barone wrote:
> Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> wrote:
>> Am 17.05.2017 um 04:26 schrieb Ralph Barone:
>>
>>> I've been doing picosecond stuff too.   16,666,666,666 ps, unfortunately.
>>
>>
>> Yeah, lots of them!
>>
> 
> It gives me more time to think over what I'm doing :-)
> 
> I used to joke that to the relaying people anything over 60 Hz was RF, and
> that to the telecom people, anything under 10.7 MHz was DC.
> 

To optical antenna people, DC goes up to 1 THz. ;)

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

[toc] | [prev] | [next] | [standalone]

#460665

AT Wednesday 17 May 2017 22:39, Phil Hobbs wrote:

> On 05/17/2017 10:31 AM, Ralph Barone wrote:
>> Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> wrote:
>>> Am 17.05.2017 um 04:26 schrieb Ralph Barone:
>>>
>>>> I've been doing picosecond stuff too.   16,666,666,666 ps,
>>>> unfortunately.
>>>
>>>
>>> Yeah, lots of them!
>>>
>> 
>> It gives me more time to think over what I'm doing :-)
>> 
>> I used to joke that to the relaying people anything over 60 Hz was RF,
>> and that to the telecom people, anything under 10.7 MHz was DC.
>> 
> 
> To optical antenna people, DC goes up to 1 THz. ;)
> 
But slowly varying DC.

-- 
Reinhardt

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#460563

Am 16.05.2017 um 20:16 schrieb John Larkin:

>> There are cases where an extra resistor is actually needed, such as a
>> base parasitic resistor or in the gate of a fast MOSFET. These can remind
>> you to include the resistor in the pcb layout, and help determine the
>> value needed in the circuit.
>
>
> I'm not likely to forget, but Spice is useless in determining the
> value that will kill oscillations. It can establish that some value
> won't slow down normal operation too much. I tend to use 33 ohms.
>
>

Yes. I second that. In simulation, my 4*IF3601 preamp is definitely
stable, but in real live:

< 
https://www.flickr.com/photos/137684711@N07/34701106245/in/album-72157662535945536/ 
 >

For most frequencies outside of the Smith diagram, if you look into
the input. Any L on the input with small enough resistance will
oscillate, including ferrite beads. The usual gate stopper is
not possible for obvious noise reasons.

:-(   Gerhard

(Sorry for the choice of colours.)

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#460631

On Tue, 16 May 2017 21:24:38 +0200, Gerhard Hoffmann
<ghf@hoffmann-hochfrequenz.de> wrote:

>Am 16.05.2017 um 20:16 schrieb John Larkin:
>
>>> There are cases where an extra resistor is actually needed, such as a
>>> base parasitic resistor or in the gate of a fast MOSFET. These can remind
>>> you to include the resistor in the pcb layout, and help determine the
>>> value needed in the circuit.
>>
>>
>> I'm not likely to forget, but Spice is useless in determining the
>> value that will kill oscillations. It can establish that some value
>> won't slow down normal operation too much. I tend to use 33 ohms.
>>
>>
>
>Yes. I second that. In simulation, my 4*IF3601 preamp is definitely
>stable, but in real live:
>
>< 
>https://www.flickr.com/photos/137684711@N07/34701106245/in/album-72157662535945536/ 
> >
>
>For most frequencies outside of the Smith diagram, if you look into
>the input. Any L on the input with small enough resistance will
>oscillate, including ferrite beads. The usual gate stopper is
>not possible for obvious noise reasons.
>
>:-(   Gerhard
>
>(Sorry for the choice of colours.)

That's an amazing part, 0.3 nv/rthz at 5 mA. As you say, you can't put
anything in series with the gate without adding Johnson noise.

Four of them is (calculates furiously) 0.15 nv/rthz!

Are the fets hard in parallel? Maybe they could run separately, and
sum downstream. I just designed an amp that has two independent gain
paths, resistively summed at the very output. 




-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#461638

Steve Wilson wrote...
>
> No matter how painful or inconvenient, LTspice is still
> orders of magnitude more useful than ASCII or hand-drawn
> schematics.

 To the contrary, this thread has illustrated that
 LTspice drawings can be utterly useless.  One can
 make a SPICE model do almost anything apparently,
 and reality has little to do with it.  In contrast,
 a hand-drawn schematic, depending on who has drawn
 it, is more likely to have knowledgeable analytical
 analysis behind it, and therefore be believable and
 eminently useful.


-- 
 Thanks,
    - Win

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#461659

On 25 May 2017 04:38:45 -0700, Winfield Hill
<hill@rowland.harvard.edu> wrote:

>Steve Wilson wrote...
>>
>> No matter how painful or inconvenient, LTspice is still
>> orders of magnitude more useful than ASCII or hand-drawn
>> schematics.
>
> To the contrary, this thread has illustrated that
> LTspice drawings can be utterly useless.  One can
> make a SPICE model do almost anything apparently,
> and reality has little to do with it.  In contrast,
> a hand-drawn schematic, depending on who has drawn
> it, is more likely to have knowledgeable analytical
> analysis behind it, and therefore be believable and
> eminently useful.

Nice book, "The Revenge of Analog." In one section, he talks about
super-high-tech companies that forbid electronic devices at design
meetings, and use whiteboards and paper.

I just discovered some wonderful new pens, Uniball Vision 0.7 mm, in
colors. They increase my IQ about 5 points.

I design on D-size vellum, with Turquoise F pencils, and I'm pretty
productive.

There seems to be a hobby of sort of randomly throwing parts onto an
LT Spice schamatic and fiddling until something happens. I love LT
Spice, but I don't trust it. I've loved women like that.


-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#461801

"John Larkin" <jjlarkin@highlandtechnology.com> wrote in message 
news:t7qdic9aaljjuvu9njqe8fusu5jj1ksv9e@4ax.com...
> Nice book, "The Revenge of Analog." In one section, he talks about
> super-high-tech companies that forbid electronic devices at design
> meetings, and use whiteboards and paper.
>

In contrast, here's a possible vision of the future:
https://youtu.be/F7yLL5fJxT4
Works fine for art.  I mean, engineering is art, too, so why not?

I'd love to have waveforms at my fingertips.

The ultimate in breadboarding: instant simulation results, without the 
trouble of soldering things together, and producing magic smoke.

Downside: while we have the computational power to do it (if not necessarily 
the optimizations to avoid Amdahl's law*), SPICE development has been 
utterly stagnant over the past three decades.  It would be foolish to think 
that would change "because VR".

But one can hope.

*Numerical simulations are timestepped, but there are some known shortcuts, 
like for quasi-periodic cycle-averaged systems, which are common enough to 
be worth addressing.  Unfortunately they aren't in any free tools...

Tim

-- 
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
Website: http://seventransistorlabs.com 

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#461805

On a sunny day (Fri, 26 May 2017 08:54:11 -0500) it happened "Tim Williams"
<tiwill@seventransistorlabs.com> wrote in <og9brk$o7r$1@dont-email.me>:

>In contrast, here's a possible vision of the future:
>https://youtu.be/F7yLL5fJxT4
>Works fine for art.  I mean, engineering is art, too, so why not?
>
>I'd love to have waveforms at my fingertips.
>
>The ultimate in breadboarding: instant simulation results, without the 
>trouble of soldering things together, and producing magic smoke.
>
>Downside: while we have the computational power to do it (if not necessarily 
>the optimizations to avoid Amdahl's law*), SPICE development has been 
>utterly stagnant over the past three decades.  It would be foolish to think 
>that would change "because VR".
>
>But one can hope.
>
>*Numerical simulations are timestepped, but there are some known shortcuts, 
>like for quasi-periodic cycle-averaged systems, which are common enough to 
>be worth addressing.  Unfortunately they aren't in any free tools...

Long time ago I tried walking into a building (where I was for the first time)
and hit the glass entrance door.
I was OK (made a loud bang, they were really concerned, told me I was number n who did that).

So, once we get used to 'virtual objects' we may get into the habit of ignoring those
and hit the real car or person ...
Then there could be no longer a difference between reality as we know it and what the machine makes us believe.
the Matrix, next you will grow up in a tube, get your brain interface,
wait, why need a brain at all, why need life.
SillyCon rules.

Maybe there is a planet somewhere where this transition did happen.
And an endless ever repeating simulation of life is all there is left.
...

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#461806

On Fri, 26 May 2017 08:54:11 -0500, "Tim Williams"
<tiwill@seventransistorlabs.com> wrote:

>"John Larkin" <jjlarkin@highlandtechnology.com> wrote in message 
>news:t7qdic9aaljjuvu9njqe8fusu5jj1ksv9e@4ax.com...
>> Nice book, "The Revenge of Analog." In one section, he talks about
>> super-high-tech companies that forbid electronic devices at design
>> meetings, and use whiteboards and paper.
>>
>
>In contrast, here's a possible vision of the future:
>https://youtu.be/F7yLL5fJxT4
>Works fine for art.  I mean, engineering is art, too, so why not?
>
>I'd love to have waveforms at my fingertips.

I love oscilloscopes. I have about 60 of them.

>
>The ultimate in breadboarding: instant simulation results, without the 
>trouble of soldering things together, and producing magic smoke.

Soldering together and measuring circuits is not only art, it's real.
I suspect that people who sell low millions of 15 cent parts will
never invest in supplying a really accurate electrical and thermal
model of their parts. They don't even edit out obvious blunders on the
data sheet, not years after being alerted to them.

>
>Downside: while we have the computational power to do it (if not necessarily 
>the optimizations to avoid Amdahl's law*), SPICE development has been 
>utterly stagnant over the past three decades.  It would be foolish to think 
>that would change "because VR".
>
>But one can hope.
>
>*Numerical simulations are timestepped, but there are some known shortcuts, 
>like for quasi-periodic cycle-averaged systems, which are common enough to 
>be worth addressing.  Unfortunately they aren't in any free tools...
>
>Tim

-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#460565

"Steve Wilson"  wrote in message 
news:XnsA776AA98AC34Eidtokenpost@69.16.179.22...

John Larkin <jjlarkin@highland_snip_technology.com> wrote:

> The current probe is twitchy. I like to add visible current-shunt
> resistors to make it easier to probe.

In SS. its place testpoint on pin. Done.

>Nothing wrong with that, except you have to add separate node names to
>either side of the resistor.

> Then instead of plotting Ib(Q2) you will plot
>I(R12). The polarity will depend on the orientation of the resistor.

Yeah, I haven't gotten round to auto sign inversion on two terminal devices. 
However, press m (mirror) of f (flip vert) and run again !

> This
>is not so bad, except you will have to turn it around to get the flow in
>>the direction you want. Or you could simply add a minus sign to the plot 
>>to
>get it to the direction you want.

>These are simple things, but are part of the huge learning curve in spice.

SS automatically puts in  zero volts source in .subckts, so again, its place 
testpoint on pin. Done.

However, I don't really agree that the is a huge learning curve in spice. 
Its all GUI for the most part. The bulk of spice is all hidden. If one can't 
figure out that running 10,000 cycles at small time steps is going to take a 
long time, I doubt if one should be using spice at all.


-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html 

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#460406

On 05/15/2017 02:29 PM, John Larkin wrote:
> On Mon, 15 May 2017 13:38:11 -0400, bitrex
> <bitrex@de.lete.earthlink.net> wrote:
>
>> On 05/15/2017 01:28 PM, John Larkin wrote:
>>
>>>>> Snoop the input current of that buffer. At 20 MHz, the overall current
>>>>> gain is less than 1. At 100 MHz, the current gain is about 0.1. You'd
>>>>> be better off with a piece of wire.
>>>>
>>>> I'm not sure what "input current" you're looking at. I'm seeing an
>>>> average current of around 600uA into the MOSFET gates at 100MHz.
>>>
>>> I put a 1 mohm resistor in series with the signal generator and probed
>>> the current, with a sine wave signal input. Try it and see what you
>>> get.
>>
>> How are the gate capacitances of the input MOSFETs supposed to be
>> charged up and down with that fuckin' thing sitting in the way?!
>>
>> Fuck the circuit to hell and then complain it's bad?! Shit! :O
>
> mohm means milliohm, in SI units and in Spice.

Ok, I see what you mean; forgive my, uh, outburst. And there is a bug 
with sine wave drive that isn't apparent with a square drive.

Problem seems to be that with these slow transistors, I optimized R9 and 
R10 to make a nice square wave. But those resistors aren't optimal for a 
sine-wave of say 1V P2P; the boost transistors never turn on hard 
enough, and if the output transistors can't get the current they need 
they're going to try to pull it from somewhere, namely from the MOSFETs. 
Or since Vds is fixed it can probably try to pull it right from the 
input source.

That's probably fixable.

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#460409

On 05/15/2017 03:05 PM, bitrex wrote:
> On 05/15/2017 02:29 PM, John Larkin wrote:
>> On Mon, 15 May 2017 13:38:11 -0400, bitrex
>> <bitrex@de.lete.earthlink.net> wrote:
>>
>>> On 05/15/2017 01:28 PM, John Larkin wrote:
>>>
>>>>>> Snoop the input current of that buffer. At 20 MHz, the overall
>>>>>> current
>>>>>> gain is less than 1. At 100 MHz, the current gain is about 0.1. You'd
>>>>>> be better off with a piece of wire.
>>>>>
>>>>> I'm not sure what "input current" you're looking at. I'm seeing an
>>>>> average current of around 600uA into the MOSFET gates at 100MHz.
>>>>
>>>> I put a 1 mohm resistor in series with the signal generator and probed
>>>> the current, with a sine wave signal input. Try it and see what you
>>>> get.
>>>
>>> How are the gate capacitances of the input MOSFETs supposed to be
>>> charged up and down with that fuckin' thing sitting in the way?!
>>>
>>> Fuck the circuit to hell and then complain it's bad?! Shit! :O
>>
>> mohm means milliohm, in SI units and in Spice.
>
> Ok, I see what you mean; forgive my, uh, outburst. And there is a bug
> with sine wave drive that isn't apparent with a square drive.
>
> Problem seems to be that with these slow transistors, I optimized R9 and
> R10 to make a nice square wave. But those resistors aren't optimal for a
> sine-wave of say 1V P2P; the boost transistors never turn on hard
> enough, and if the output transistors can't get the current they need
> they're going to try to pull it from somewhere, namely from the MOSFETs.
> Or since Vds is fixed it can probably try to pull it right from the
> input source.
>
> That's probably fixable.

But it doesn't necessarily make sense to view a square wave as a Fourier 
series and judge the performance of a square-wave amplifier based on how 
well it amplifies a sine wave at the fundamental frequency if the 
system's parameters are not essentially LTI.

If the bias of the amplifier is changing an enormous amount in response 
to certain signal amplitudes then it isn't really LTI. If one were 
clever or use even more parts I think it would be possible to slide the 
bias in a more uniform fashion to eliminate the non-linearity, but as it 
stands now the shift looks pretty bang-bang.

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#460424

On Mon, 15 May 2017 15:05:51 -0400, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 05/15/2017 02:29 PM, John Larkin wrote:
>> On Mon, 15 May 2017 13:38:11 -0400, bitrex
>> <bitrex@de.lete.earthlink.net> wrote:
>>
>>> On 05/15/2017 01:28 PM, John Larkin wrote:
>>>
>>>>>> Snoop the input current of that buffer. At 20 MHz, the overall current
>>>>>> gain is less than 1. At 100 MHz, the current gain is about 0.1. You'd
>>>>>> be better off with a piece of wire.
>>>>>
>>>>> I'm not sure what "input current" you're looking at. I'm seeing an
>>>>> average current of around 600uA into the MOSFET gates at 100MHz.
>>>>
>>>> I put a 1 mohm resistor in series with the signal generator and probed
>>>> the current, with a sine wave signal input. Try it and see what you
>>>> get.
>>>
>>> How are the gate capacitances of the input MOSFETs supposed to be
>>> charged up and down with that fuckin' thing sitting in the way?!
>>>
>>> Fuck the circuit to hell and then complain it's bad?! Shit! :O
>>
>> mohm means milliohm, in SI units and in Spice.
>
>Ok, I see what you mean; forgive my, uh, outburst. And there is a bug 
>with sine wave drive that isn't apparent with a square drive.
>
>Problem seems to be that with these slow transistors, I optimized R9 and 
>R10 to make a nice square wave. But those resistors aren't optimal for a 
>sine-wave of say 1V P2P; the boost transistors never turn on hard 
>enough, and if the output transistors can't get the current they need 
>they're going to try to pull it from somewhere, namely from the MOSFETs. 
>Or since Vds is fixed it can probably try to pull it right from the 
>input source.
>
>That's probably fixable.

You might use some smaller mosfets; those are 10 amp beasts.

Or bipolars. A spin on Jan's 4-transistor circuit should work.




-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#460428

John Larkin <jjlarkin@highland_snip_technology.com> wrote:

>>That's probably fixable.
 
> You might use some smaller mosfets; those are 10 amp beasts.
 
> Or bipolars. A spin on Jan's 4-transistor circuit should work.

If you are speaking of the complmentary emitter-follower circuit, it is not 
new. I used it in 1979 and shipped it in millions of dollars worth of 
products in 1980's dollars. 

HP thought it was excellent, which led to several hundred thousand dollar 
sales. 

I don't know if it has a name, but it is also shown in numerous web sites 
today.

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