On Tuesday, May 26, 2020 at 1:17:58 PM UTC-4, jla...@highlandsniptechnology.com wrote:
> On Tue, 26 May 2020 12:43:12 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> 
> >On 2020-05-26 12:29, jlarkin@highlandsniptechnology.com wrote:
> >> On Tue, 26 May 2020 12:12:56 -0400, Phil Hobbs
> >> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> >> 
> >>> On 2020-05-26 11:59, Michael Terrell wrote:
> >>>> On Tuesday, May 26, 2020 at 10:16:29 AM UTC-4, Phil Hobbs wrote:
> >>>>> On 2020-05-26 09:01, Michael Terrell
> >>>>>>
> >>>>>> The 3N128 was popular in Amateur Radio projects in the '70s along with RCA's 40673 that was used in TV tuners and garage door openers. They used to cost me 36 cents, from the Linear corporation that built the openers. I bought them 25 at a time, and often ran out before more were available. These were very sensitive receivers, and with careful alignment many would operate a door from three blocks away. That was handy for fire stations. They could start the doors to open and have them open enough that they didn't have to wait to pull off the road when they returned after a fire run. the 406743 turn up in small batches from time to time, but they aren't worth $20 each.
> >>>>>
> >>>>> You can do the equivalent with a built-up cascode anyway.
> >>>>>
> >>>>> My very favorite dual-gate part was the Motorola MRF966 GaAs FET.  You
> >>>>> just connected gate 2 to the source, and, presto, an almost perfectly
> >>>>> unilateral amplifier.  I used to get > 70 dB isolation up to above 100
> >>>>> MHz with one stage.
> >>>>>
> >>>>> I used to use them connected directly to coax as cheapo FET probes--the
> >>>>> pointy leads of the Macro-X package were perfect for that.
> >>>>>
> >>>>> I still have a couple of dozen, but haven't used one in ages.
> >>>>
> >>>>
> >>>> Back then, I only had a branch of Pioneer to buy parts from. It was called SREPCO, and it carried TV repair parts. Pioneer had an industrial branch in Dayton, Ohio but they only sold to corporations listed on Dunn and Bradstreet. SREPCO was a very early distributor in Electronics 'Standard Radio and Electronic Parts Company'. Those stores were closed, decades ago.
> >>>>
> >>>
> >>> In Vancouver things were a bit looser--you just needed to make up a
> >>> company name.  A pal of mine called his "Enematronics" and nobody batted
> >>> an eyelash.
> >> 
> >> I participated in the design of Ez-Em, a medical device. That's all
> >> I'll say about that.
> >> 
> >> I did invent a company, Simple Systems Inc, so I could get the free
> >> electronics magazines, back when they were worth getting.
> >> 
> >>>
> >>> Canadian Electronics Limited (CEL) and Armaco were the leading places,
> >>> but besides them and Rat Shack there was a ham shop within easy
> >>> bicycling distance, called "Rendell-Paret Electronics", run by the
> >>> estimable Hedley Rendell.  (Not Hedy.)
> >> 
> >> I used to take the St Charles line streetcar to Radio Parts on Lee
> >> Circle in New Orleans. Giant statue of Robert E Lee, with his back to
> >> the north. More often than not, they would give me parts. Once the
> >> owner gave me a 10-turn pot and dial, which overwhelmed me. Probably
> >> nobody else in New Orleans wanted it anyhow.
> >> 
> >>>
> >>> It was one of those grease-and-nicotine-encrusted places with old gear
> >>> piled right up to the ceiling, barrels of surplus parts, the works.
> >>> Hedley was always chain-smoking behind the counter.  If there had been
> >>> an earthquake, nobody would have gotten out alive.
> >> 
> >> Mike Quinn Electronics, in a quonset hut at the Oakland airport, was a
> >> death trap.
> >> 
> >> All the surplus places are gone around here. There used to be one on
> >> Market Street in downtown San Francisco.
> >
> >Yeah, they knocked down Radio Row on Canal St to build the WTC.
> >
> >Dave Jones has a video of a place in (iirc) Burbank that has all sorts 
> >of old missile parts and stuff.
> >
> >Apart from the nostalgia value, we're way, way better off now.
> >
> >Cheers
> >
> >Phil Hobbs
> 
> Yes. Amazon has amazing stuff, and no streetcar ride.

Not for you, but the warehouses that Amazon fills with people are breeding grounds for the virus.  Many employees have quit and when employees speak out about better working conditions they get fired.  I seldom use Amazon because there are always better alternatives.  Amazon is the easy choice for people who don't like to think. 

-- 

  Rick C.

  + Get 1,000 miles of free Supercharging
  + Tesla referral code - https://ts.la/richard11209

On 2020-05-27 14:20, John Larkin wrote:
> On Wed, 27 May 2020 02:20:56 +0000 (UTC), Cydrome Leader
> <presence@MUNGEpanix.com> wrote:
> 
>> Michael Terrell <terrell.michael.a@gmail.com> wrote:
>>> On Tuesday, May 26, 2020 at 10:47:06 AM UTC-4,John Larkin wrote:
>>>>
>>>> Unijunctions, point-contact diodes and transistors, some strange
>>>> 4-layer things that played a part in Silicon Valley history, germanium
>>>> jfets, tunnel diodes, electrolytic transistors, alloy-junction
>>>> transistors, surface-barrier transistors, Schottky transistors, drift
>>>> step-recovery diodes, dual-gate fets, reference zeners, silicon
>>>> varistors, mesfets (almost gone), all kinds of weird stuff.
>>>
>>> Try to find a Stabistor these days. HP used them in the Harrison Labs
>>> designed power supplies as a reference. If it fails, all the outputs are
>>> wrong. I have several HP6236B supplies with bad Stabistors.  I had to
>>> resort to buying a couple of the less popular 6237B model, for parts.
>>
>> I had to lookup the electrolyic transistor. What's the reason these odd
>> devices went away?
> 
> Expensive, unreliable, slow, big, noisy. You can put a lot of BCX70s
> on a 6" wafer.
> 
> 
> I get the point contact diodes and transistors are just
>> obsolete, but since when are zeners going away?
> 
> Bandgaps are better at low voltages, but zeners are still popular.

They're dramatically faster and tougher, for one reason.

> 
>>
>> Has anyone here used any SiC power semiconductors?
> 
> I've used SiC diodes and the Cree and ST power fets. They are fabulous
> at high voltages, but hard to drive. I'm driving one from -8 to almost
> +20 on the gate in a few ns, and there are no commercial drivers that
> will do that.
> 
> The 1200 volt Cree parts sort of zener around 1600 volts or so on the
> drain, without damage. But you can blow out the gates driving them a
> little harder than you need to.
> 
> The Cree substrate diode model is a joke.

Are there any good MOSFET substrate models?

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Wed, 27 May 2020 02:20:56 +0000 (UTC), Cydrome Leader
<presence@MUNGEpanix.com> wrote:

>Michael Terrell <terrell.michael.a@gmail.com> wrote:
>> On Tuesday, May 26, 2020 at 10:47:06 AM UTC-4,John Larkin wrote:
>>> 
>>> Unijunctions, point-contact diodes and transistors, some strange
>>> 4-layer things that played a part in Silicon Valley history, germanium
>>> jfets, tunnel diodes, electrolytic transistors, alloy-junction
>>> transistors, surface-barrier transistors, Schottky transistors, drift
>>> step-recovery diodes, dual-gate fets, reference zeners, silicon
>>> varistors, mesfets (almost gone), all kinds of weird stuff.
>> 
>> Try to find a Stabistor these days. HP used them in the Harrison Labs 
>> designed power supplies as a reference. If it fails, all the outputs are 
>> wrong. I have several HP6236B supplies with bad Stabistors.  I had to 
>> resort to buying a couple of the less popular 6237B model, for parts.
>
>I had to lookup the electrolyic transistor. What's the reason these odd 
>devices went away? 

Expensive, unreliable, slow, big, noisy. You can put a lot of BCX70s
on a 6" wafer.


I get the point contact diodes and transistors are just 
>obsolete, but since when are zeners going away?

Bandgaps are better at low voltages, but zeners are still popular.

>
>Has anyone here used any SiC power semiconductors?

I've used SiC diodes and the Cree and ST power fets. They are fabulous
at high voltages, but hard to drive. I'm driving one from -8 to almost
+20 on the gate in a few ns, and there are no commercial drivers that
will do that.

The 1200 volt Cree parts sort of zener around 1600 volts or so on the
drain, without damage. But you can blow out the gates driving them a
little harder than you need to.

The Cree substrate diode model is a joke.

-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

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

On Tue, 26 May 2020 19:53:18 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:

>On Tuesday, May 26, 2020 at 7:47:06 AM UTC-7, jla...@highlandsniptechnology.com wrote:
>> On Mon, 25 May 2020 23:49:19 +0000 (UTC), Cydrome Leader
>> <presence@MUNGEpanix.com> wrote:
>
>> >A very odd device. Are there other weird semiconductors like that?
>> 
>> Unijunctions, point-contact diodes and transistors, some strange
>> 4-layer things that played a part in Silicon Valley history, germanium
>> jfets, tunnel diodes, electrolytic transistors, alloy-junction
>> transistors, surface-barrier transistors, Schottky transistors, drift
>> step-recovery diodes, dual-gate fets, reference zeners, silicon
>> varistors, mesfets (almost gone), all kinds of weird stuff.
>
>One of the oddest is Ge(Li) diodes.   Called 'jelly detectors', they had
>to be kept cold (liquid nitrogen temperature).   Continuously.   Not just
>in operation, but all the way from the factory to the point-of-use.
>
>And, of course, the selenium drum in the old Xerox machines is an
>odd semiconductor.

Selenium and copper-oxide rectifiers too.



-- 

John Larkin         Highland Technology, Inc

Science teaches us to doubt.

  Claude Bernard
  

Am 26.05.20 um 16:46 schrieb jlarkin@highlandsniptechnology.com:
> On Mon, 25 May 2020 23:49:19 +0000 (UTC), Cydrome Leader

>> A very odd device. Are there other weird semiconductors like that?
> 
> Unijunctions, point-contact diodes and transistors, some strange
> 4-layer things that played a part in Silicon Valley history, germanium
> jfets, tunnel diodes, electrolytic transistors, alloy-junction
> transistors, surface-barrier transistors, Schottky transistors, drift
> step-recovery diodes, dual-gate fets, reference zeners, silicon
> varistors, mesfets (almost gone), all kinds of weird stuff.

There must have been a device called PITRAN.
Pressure sensitive transistor, proposed for microphones.

Cheers, Gerhard

On 2020-05-26 22:53, whit3rd wrote:
> On Tuesday, May 26, 2020 at 7:47:06 AM UTC-7, jla...@highlandsniptechnology.com wrote:
>> On Mon, 25 May 2020 23:49:19 +0000 (UTC), Cydrome Leader
>> <presence@MUNGEpanix.com> wrote:
> 
>>> A very odd device. Are there other weird semiconductors like that?
>>
>> Unijunctions, point-contact diodes and transistors, some strange
>> 4-layer things that played a part in Silicon Valley history, germanium
>> jfets, tunnel diodes, electrolytic transistors, alloy-junction
>> transistors, surface-barrier transistors, Schottky transistors, drift
>> step-recovery diodes, dual-gate fets, reference zeners, silicon
>> varistors, mesfets (almost gone), all kinds of weird stuff.
> 
> One of the oddest is Ge(Li) diodes.   Called 'jelly detectors', they had
> to be kept cold (liquid nitrogen temperature).   Continuously.   Not just
> in operation, but all the way from the factory to the point-of-use.


Lithium-drifted silicon [Si(Li)] and germanium [Ge(Li)] are ancient 
history--they went out about 1980, when boules of higher purity became 
available.

The lithium drifting was intended to make them behave more like 
intrinsic semiconductors.

If a Ge(Li) detector warmed up, it decayed with a time constant roughly 
like fresh fish.  It could be re-drifted once, with some performance 
degradation, but if it happened twice it was toast.  Fortunately 
intrinsic Ge detectors are tougher that way.

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Tuesday, May 26, 2020 at 7:47:06 AM UTC-7, jla...@highlandsniptechnology.com wrote:
> On Mon, 25 May 2020 23:49:19 +0000 (UTC), Cydrome Leader
> <presence@MUNGEpanix.com> wrote:

> >A very odd device. Are there other weird semiconductors like that?
> 
> Unijunctions, point-contact diodes and transistors, some strange
> 4-layer things that played a part in Silicon Valley history, germanium
> jfets, tunnel diodes, electrolytic transistors, alloy-junction
> transistors, surface-barrier transistors, Schottky transistors, drift
> step-recovery diodes, dual-gate fets, reference zeners, silicon
> varistors, mesfets (almost gone), all kinds of weird stuff.

One of the oddest is Ge(Li) diodes.   Called 'jelly detectors', they had
to be kept cold (liquid nitrogen temperature).   Continuously.   Not just
in operation, but all the way from the factory to the point-of-use.

And, of course, the selenium drum in the old Xerox machines is an
odd semiconductor.

Michael Terrell <terrell.michael.a@gmail.com> wrote:
> On Tuesday, May 26, 2020 at 10:47:06 AM UTC-4,John Larkin wrote:
>> 
>> Unijunctions, point-contact diodes and transistors, some strange
>> 4-layer things that played a part in Silicon Valley history, germanium
>> jfets, tunnel diodes, electrolytic transistors, alloy-junction
>> transistors, surface-barrier transistors, Schottky transistors, drift
>> step-recovery diodes, dual-gate fets, reference zeners, silicon
>> varistors, mesfets (almost gone), all kinds of weird stuff.
> 
> Try to find a Stabistor these days. HP used them in the Harrison Labs 
> designed power supplies as a reference. If it fails, all the outputs are 
> wrong. I have several HP6236B supplies with bad Stabistors.  I had to 
> resort to buying a couple of the less popular 6237B model, for parts.

I had to lookup the electrolyic transistor. What's the reason these odd 
devices went away? I get the point contact diodes and transistors are just 
obsolete, but since when are zeners going away?

Has anyone here used any SiC power semiconductors?

On Tue, 26 May 2020 12:43:12 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>On 2020-05-26 12:29, jlarkin@highlandsniptechnology.com wrote:
>> On Tue, 26 May 2020 12:12:56 -0400, Phil Hobbs
>> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>> 
>>> On 2020-05-26 11:59, Michael Terrell wrote:
>>>> On Tuesday, May 26, 2020 at 10:16:29 AM UTC-4, Phil Hobbs wrote:
>>>>> On 2020-05-26 09:01, Michael Terrell
>>>>>>
>>>>>> The 3N128 was popular in Amateur Radio projects in the '70s along with RCA's 40673 that was used in TV tuners and garage door openers. They used to cost me 36 cents, from the Linear corporation that built the openers. I bought them 25 at a time, and often ran out before more were available. These were very sensitive receivers, and with careful alignment many would operate a door from three blocks away. That was handy for fire stations. They could start the doors to open and have them open enough that they didn't have to wait to pull off the road when they returned after a fire run. the 406743 turn up in small batches from time to time, but they aren't worth $20 each.
>>>>>
>>>>> You can do the equivalent with a built-up cascode anyway.
>>>>>
>>>>> My very favorite dual-gate part was the Motorola MRF966 GaAs FET.  You
>>>>> just connected gate 2 to the source, and, presto, an almost perfectly
>>>>> unilateral amplifier.  I used to get > 70 dB isolation up to above 100
>>>>> MHz with one stage.
>>>>>
>>>>> I used to use them connected directly to coax as cheapo FET probes--the
>>>>> pointy leads of the Macro-X package were perfect for that.
>>>>>
>>>>> I still have a couple of dozen, but haven't used one in ages.
>>>>
>>>>
>>>> Back then, I only had a branch of Pioneer to buy parts from. It was called SREPCO, and it carried TV repair parts. Pioneer had an industrial branch in Dayton, Ohio but they only sold to corporations listed on Dunn and Bradstreet. SREPCO was a very early distributor in Electronics 'Standard Radio and Electronic Parts Company'. Those stores were closed, decades ago.
>>>>
>>>
>>> In Vancouver things were a bit looser--you just needed to make up a
>>> company name.  A pal of mine called his "Enematronics" and nobody batted
>>> an eyelash.
>> 
>> I participated in the design of Ez-Em, a medical device. That's all
>> I'll say about that.
>> 
>> I did invent a company, Simple Systems Inc, so I could get the free
>> electronics magazines, back when they were worth getting.
>> 
>>>
>>> Canadian Electronics Limited (CEL) and Armaco were the leading places,
>>> but besides them and Rat Shack there was a ham shop within easy
>>> bicycling distance, called "Rendell-Paret Electronics", run by the
>>> estimable Hedley Rendell.  (Not Hedy.)
>> 
>> I used to take the St Charles line streetcar to Radio Parts on Lee
>> Circle in New Orleans. Giant statue of Robert E Lee, with his back to
>> the north. More often than not, they would give me parts. Once the
>> owner gave me a 10-turn pot and dial, which overwhelmed me. Probably
>> nobody else in New Orleans wanted it anyhow.
>> 
>>>
>>> It was one of those grease-and-nicotine-encrusted places with old gear
>>> piled right up to the ceiling, barrels of surplus parts, the works.
>>> Hedley was always chain-smoking behind the counter.  If there had been
>>> an earthquake, nobody would have gotten out alive.
>> 
>> Mike Quinn Electronics, in a quonset hut at the Oakland airport, was a
>> death trap.
>> 
>> All the surplus places are gone around here. There used to be one on
>> Market Street in downtown San Francisco.
>
>Yeah, they knocked down Radio Row on Canal St to build the WTC.
>
>Dave Jones has a video of a place in (iirc) Burbank that has all sorts 
>of old missile parts and stuff.
>
>Apart from the nostalgia value, we're way, way better off now.
>
>Cheers
>
>Phil Hobbs

Yes. Amazon has amazing stuff, and no streetcar ride.



-- 

John Larkin         Highland Technology, Inc

Science teaches us to doubt.

  Claude Bernard
  

On 2020-05-26 12:29, jlarkin@highlandsniptechnology.com wrote:
> On Tue, 26 May 2020 12:12:56 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
> 
>> On 2020-05-26 11:59, Michael Terrell wrote:
>>> On Tuesday, May 26, 2020 at 10:16:29 AM UTC-4, Phil Hobbs wrote:
>>>> On 2020-05-26 09:01, Michael Terrell
>>>>>
>>>>> The 3N128 was popular in Amateur Radio projects in the '70s along with RCA's 40673 that was used in TV tuners and garage door openers. They used to cost me 36 cents, from the Linear corporation that built the openers. I bought them 25 at a time, and often ran out before more were available. These were very sensitive receivers, and with careful alignment many would operate a door from three blocks away. That was handy for fire stations. They could start the doors to open and have them open enough that they didn't have to wait to pull off the road when they returned after a fire run. the 406743 turn up in small batches from time to time, but they aren't worth $20 each.
>>>>
>>>> You can do the equivalent with a built-up cascode anyway.
>>>>
>>>> My very favorite dual-gate part was the Motorola MRF966 GaAs FET.  You
>>>> just connected gate 2 to the source, and, presto, an almost perfectly
>>>> unilateral amplifier.  I used to get > 70 dB isolation up to above 100
>>>> MHz with one stage.
>>>>
>>>> I used to use them connected directly to coax as cheapo FET probes--the
>>>> pointy leads of the Macro-X package were perfect for that.
>>>>
>>>> I still have a couple of dozen, but haven't used one in ages.
>>>
>>>
>>> Back then, I only had a branch of Pioneer to buy parts from. It was called SREPCO, and it carried TV repair parts. Pioneer had an industrial branch in Dayton, Ohio but they only sold to corporations listed on Dunn and Bradstreet. SREPCO was a very early distributor in Electronics 'Standard Radio and Electronic Parts Company'. Those stores were closed, decades ago.
>>>
>>
>> In Vancouver things were a bit looser--you just needed to make up a
>> company name.  A pal of mine called his "Enematronics" and nobody batted
>> an eyelash.
> 
> I participated in the design of Ez-Em, a medical device. That's all
> I'll say about that.
> 
> I did invent a company, Simple Systems Inc, so I could get the free
> electronics magazines, back when they were worth getting.
> 
>>
>> Canadian Electronics Limited (CEL) and Armaco were the leading places,
>> but besides them and Rat Shack there was a ham shop within easy
>> bicycling distance, called "Rendell-Paret Electronics", run by the
>> estimable Hedley Rendell.  (Not Hedy.)
> 
> I used to take the St Charles line streetcar to Radio Parts on Lee
> Circle in New Orleans. Giant statue of Robert E Lee, with his back to
> the north. More often than not, they would give me parts. Once the
> owner gave me a 10-turn pot and dial, which overwhelmed me. Probably
> nobody else in New Orleans wanted it anyhow.
> 
>>
>> It was one of those grease-and-nicotine-encrusted places with old gear
>> piled right up to the ceiling, barrels of surplus parts, the works.
>> Hedley was always chain-smoking behind the counter.  If there had been
>> an earthquake, nobody would have gotten out alive.
> 
> Mike Quinn Electronics, in a quonset hut at the Oakland airport, was a
> death trap.
> 
> All the surplus places are gone around here. There used to be one on
> Market Street in downtown San Francisco.

Yeah, they knocked down Radio Row on Canal St to build the WTC.

Dave Jones has a video of a place in (iirc) Burbank that has all sorts 
of old missile parts and stuff.

Apart from the nostalgia value, we're way, way better off now.

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com