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Groups > sci.electronics.design > #447222
| From | Joerg <news@analogconsultants.com> |
|---|---|
| Newsgroups | sci.electronics.design |
| Subject | Re: An old "500MC biquinary counter" |
| Date | 2017-02-10 14:55 -0800 |
| Message-ID | <eg6um3FmimlU1@mid.individual.net> (permalink) |
| References | <M0mnA.448$SQ3.75@fx29.iad> <eg6ag4Fig75U1@mid.individual.net> <o7l7tq$fq1$1@dont-email.me> <eg6peeFli2gU1@mid.individual.net> <o7ld1a$2gk$1@dont-email.me> |
On 2017-02-10 09:50, Phil Hobbs wrote: > On 02/10/2017 04:26 PM, Joerg wrote: >> On 2017-02-10 12:32, Piglet wrote: >>> On 10/02/2017 17:10, Joerg wrote: >>>> On 2017-02-10 08:39, bitrex wrote: >>>>> What are D1-D5? >>>>> >>>>> http://www.seekic.com/uploadfile/ic-circuit/s2009713233931554.gif >>>> >>>> >>>> Could they be Shockley diodes? Those are similar to SCRs but without a >>>> gate connection and can only be triggered via avalanche breakdown or >>>> dv/dt. >>>> >>> >>> Yeah could be Shockley diodes (aka 4-layer diodes) but last time I saw >>> one in a schematic the symbol was different. However they are not >>> hi-speed parts and even in their heyday would not have seen use at 00s >>> of kilohertz let alone megahertz. >>> >> >> Schematic symbols in the olden days were often weird. Take a look at the >> potmeter representations here (9th and 10th left from the top): >> >> http://www.radiomuseum.org/forumdata/users/133/Symbols_2_590.png >> >> >>> Diac is a still-available kindof breakover diode but higher voltage and >>> bidirectional. 4-layer diodes I saw were made with breakover voltages >>> from 8 to 22V and 5-10% tolerance. TC was remarkable good and they made >>> good semi-precise timers (but not for nano-seconds). Diacs typically >>> breakover 28-35V and are not tightly specified. >>> >>> Another option is that is just an old symbol for a zener diode? >>> >>> But for those speeds I reckon they must be tunnel diodes. That would tie >>> in with the emitter coupled logic and 10mA tail current. Tunnel diodes >>> are fast. Due to the very high doping some older ones have now diffused >>> themselves into mush. >>> >> >> That IC could be from an era where a few hundred kHz was considered >> blazingly fast. Shockley diodes would offer the nice advantage of >> introducing hysteresis which improves the noise robustness of this >> counter. >> >> With tunnel diodes I wouldn't know who they'd integrate those onto a >> chip. >> > > Well, it does say "500MC biquinary counter". ;) > > I suspect it was never an actual IC. > With 2k resistors and stuff in there it would never even get into the VHF range :-) -- Regards, Joerg http://www.analogconsultants.com/
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An old "500MC biquinary counter" bitrex <bitrex@de.lete.earthlink.net> - 2017-02-10 11:39 -0500
Re: An old "500MC biquinary counter" Joerg <news@analogconsultants.com> - 2017-02-10 09:10 -0800
Re: An old "500MC biquinary counter" "tom" <tmiller11147@verizon.net> - 2017-02-10 13:24 -0500
Re: An old "500MC biquinary counter" John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-02-10 11:30 -0800
Re: An old "500MC biquinary counter" pcdhobbs@gmail.com - 2017-02-10 12:36 -0800
Re: An old "500MC biquinary counter" John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-02-10 14:15 -0800
Re: An old "500MC biquinary counter" Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-10 13:16 -0500
Re: An old "500MC biquinary counter" John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-02-10 16:14 -0800
Re: An old "500MC biquinary counter" Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-10 19:19 -0500
Re: An old "500MC biquinary counter" pcdhobbs@gmail.com - 2017-02-10 10:23 -0800
Re: An old "500MC biquinary counter" Joerg <news@analogconsultants.com> - 2017-02-10 11:16 -0800
Re: An old "500MC biquinary counter" John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-02-10 11:27 -0800
Re: An old "500MC biquinary counter" pcdhobbs@gmail.com - 2017-02-10 12:32 -0800
Re: An old "500MC biquinary counter" bill.sloman@ieee.org - 2017-02-10 16:05 -0800
Re: An old "500MC biquinary counter" "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-11 10:28 -0600
Re: An old "500MC biquinary counter" Piglet <erichpwagner@hotmail.com> - 2017-02-10 20:32 +0000
Re: An old "500MC biquinary counter" Joerg <news@analogconsultants.com> - 2017-02-10 13:26 -0800
Re: An old "500MC biquinary counter" Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-10 12:50 -0500
Re: An old "500MC biquinary counter" Joerg <news@analogconsultants.com> - 2017-02-10 14:55 -0800
Re: An old "500MC biquinary counter" - 500 MC Bi-Quinary Counter.gif (0/1) Dave M <dgminala at mediacombb dot net> - 2017-02-10 18:41 -0600
Re: An old "500MC biquinary counter" - 500 MC Bi-Quinary Counter.gif (0/1) "Dave M" <dgminala@mediacombb.net> - 2017-02-10 18:50 -0600
Re: An old "500MC biquinary counter" - 500 MC Bi-Quinary Counter.gif (0/1) Joerg <news@analogconsultants.com> - 2017-02-10 16:58 -0800
Re: An old "500MC biquinary counter" - 500 MC Bi-Quinary Counter.gif (0/1) Clifford Heath <no.spam@please.net> - 2017-02-11 14:29 +1100
Re: An old "500MC biquinary counter" - 500 MC Bi-Quinary Counter.gif (0/1) whit3rd <whit3rd@gmail.com> - 2017-02-11 02:48 -0800
Re: An old "500MC biquinary counter" Piglet <erichpwagner@hotmail.com> - 2017-02-11 11:00 +0000
Re: An old "500MC biquinary counter" "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> - 2017-02-11 20:57 -0500
Re: An old "500MC biquinary counter" krw@notreal.com - 2017-02-11 22:07 -0500
Re: An old "500MC biquinary counter" Clifford Heath <no.spam@please.net> - 2017-02-12 18:21 +1100
Re: An old "500MC biquinary counter" krw@notreal.com - 2017-02-12 17:04 -0500
Re: An old "500MC biquinary counter" Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-02-10 14:40 -0700
Re: An old "500MC biquinary counter" bitrex <bitrex@de.lete.earthlink.net> - 2017-02-10 17:59 -0500
Re: An old "500MC biquinary counter" bitrex <bitrex@de.lete.earthlink.net> - 2017-02-10 18:04 -0500
Re: An old "500MC biquinary counter" dagmargoodboat@yahoo.com - 2017-02-11 06:41 -0800
Re: An old "500MC biquinary counter" rickman <gnuarm@gmail.com> - 2017-02-11 07:10 -0500
Re: An old "500MC biquinary counter" bitrex <bitrex@de.lete.earthlink.net> - 2017-02-11 11:36 -0500
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