Path: Xl.tags.giganews.com!local-2.nntp.ord.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail
NNTP-Posting-Date: Fri, 17 May 2024 02:06:27 +0000
From: John Larkin <jjSNIPlarkin@highNONOlandtechnology.com>
Newsgroups: sci.electronics.design
Subject: Re: fast discrete PHEMT one-shot
Date: Thu, 16 May 2024 19:04:32 -0700
Organization: Highland Tech
Reply-To: xx@yy.com
Message-ID: <22ed4jl7ups3c3gjp4mull78gq5aq9rclu@4ax.com>
References: <q0p94jh3tkrbenq67jpbkpfb45e744cpt5@4ax.com> <v23e03$14plf$1@dont-email.me> <48na4j10neo6bru36kllgm3447dclcrfgg@4ax.com> <v255tb$1k81d$1@dont-email.me> <9qdc4jdovsm0rousj88ngtn2bj6env9l48@4ax.com> <v25r1d$6pq$1@nnrp.usenet.blueworldhosting.com>
X-Newsreader: Forte Agent 3.1/32.783
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Lines: 81
X-Trace: sv3-IFK7EC9pMpedSLJ9/AkZi1o9N7/mpMXu6rzsoohfss/sE2p/Y4fbVKXSOIlzRg2BGRfBKQgN9o+n8Yr!nQrRSDEpRuPheHrzy5ckL5gqkypEAnZExCuf7rnrkLFeRnA7IANCo0244aVPYruuHf7+8oM9mGwX!2KfN4g==
X-Complaints-To: www.supernews.com/docs/abuse.html
X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html
X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly
X-Postfilter: 1.3.40
Bytes: 4480

On Thu, 16 May 2024 16:41:15 -0400, "Edward Rawde"
<invalid@invalid.invalid> wrote:

>"John Larkin" <jjSNIPlarkin@highNONOlandtechnology.com> wrote in message 
>news:9qdc4jdovsm0rousj88ngtn2bj6env9l48@4ax.com...
>> On Fri, 17 May 2024 00:40:32 +1000, Bill Sloman <bill.sloman@ieee.org>
>> wrote:
>>
>>>On 16/05/2024 11:15 am, John Larkin wrote:
>>>> On Wed, 15 May 2024 22:46:27 -0000 (UTC), piglet
>>>> <erichpwagner@hotmail.com> wrote:
>>>>
>>>>> John Larkin <jjSNIPlarkin@highNONOlandtechnology.com> wrote:
>>>>>>
>>>>>> https://www.dropbox.com/scl/fi/agatzclr8pvr5470g6mc4/Phemt_One_Shot_1.jpg?rlkey=cwnx0qd7ajgnh8otf627x5lku&raw=1
>>>>>>
>>>>>> Regular monostables are terribly slow. This one has low prop delay and
>>>>>> high rep-rate, if the sim is to be believed.
>>>>>>
>>>>>> SAV541 is mostly specified as an RF part, but it's a dynamite switch.
>>>>>>
>>>>>> I can post a link to the files if anybody wants to play with this. All
>>>>>> my values are first guesses, no math involved, and it works!
>>>>>>
>>>>>> My SAV541 Spice model is a revision of Phil Hobbs' original.
>>>>>> Mini-Circuits is adamant that they will never provide Spice models, a
>>>>>> typical RF-bigot attitude.
>>>>>>
>>>>>>
>>>>>
>>>>> Yay! Eccles-Jordan ride again.
>>>>
>>>> 1918!
>>>>
>>>> I think that was a bistable. I don't know when the monostable was > 
>>>> invented.
>>>
>>>https://en.wikipedia.org/wiki/Multivibrator
>>>
>>>has a two quotes from 1942 one from 1943 and two from 1949 which make it
>>>clear that monostable had been invented by then. It sees it as a cut
>>>down bistable, so Eccles-Jordan is probably a good name.
>>>
>>>Since the first multivibrator circuit, the astable multivibrator
>>>oscillator, was invented by Henri Abraham and Eugene Bloch during World
>>>War I, it probably isn't the right name.
>>>
>>>https://apps.dtic.mil/sti/tr/pdf/AD0410225.pdf
>>>
>>>is a 1963 Ph.D. on the bistable circuit.
>>>
>>>> People tend to roll eyes when I use one-shots in logic designs. I
>>>> can't see why.
>>>
>>>You can't trigger a one-shot immediately after it has been triggered,
>>>and the pulse width you get can be reduced if you re-trigger it too soon
>>>after it has generated it's pulse, when it hasn't entirely recovered.
>>
>> The SN74123 retriggerable one-shot, and a Fairchild equivalent, are
>> over 50 years old.
>>
>> And "it's" is not the possessive form. It's means "it is."
>
>But it can also mean "it has" and who cares anyway.
>I often find, when typing fast, that I used the wrong form when I re read my 
>sentence.
>I even typed dentence then and had to change the d.

You've got to admit that his pompous lecture, about all the inherent
defects of one-shots, was amusing.

I tweaked my phemt one-shot a bit, just for fun. I might even have a
use for it.

https://www.dropbox.com/scl/fi/zoncsuiz2ifl30i1tw0cl/Phemt_One-shot_2.jpg?rlkey=z77hx5kkdpijmz5rs7ex63jq7&raw=1


One cool old circuit that predated ICs was the uni-shot, a single
transistor and three passives. It was used in model airplane r/c
transmitters. One of the three passives was a joystick pot.