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Groups > sci.electronics.design > #450540 > unrolled thread
| Started by | John Larkin <jjlarkinxyxy@highlandtechnology.com> |
|---|---|
| First post | 2017-03-06 16:51 -0800 |
| Last post | 2017-03-11 21:04 -0500 |
| Articles | 20 on this page of 96 — 20 participants |
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RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 16:51 -0800
Re: RF bipolars RIP Winfield Hill <hill@rowland.harvard.edu> - 2017-03-06 18:01 -0800
Re: RF bipolars RIP Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> - 2017-03-07 03:19 +0100
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 18:25 -0800
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-06 19:03 -0800
Re: RF bipolars RIP Winfield Hill <hill@rowland.harvard.edu> - 2017-03-06 19:11 -0800
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-06 20:40 -0800
Re: RF bipolars RIP Joerg <news@analogconsultants.com> - 2017-03-07 07:28 -0800
Re: RF bipolars RIP Winfield Hill <hill@rowland.harvard.edu> - 2017-03-06 18:31 -0800
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-06 20:44 -0800
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 10:17 -0500
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-07 08:08 -0800
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 12:15 -0500
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-07 09:30 -0800
Re: RF bipolars RIP Joerg <news@analogconsultants.com> - 2017-03-07 09:33 -0800
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 12:44 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-07 17:53 +0000
Re: RF bipolars RIP Joerg <news@analogconsultants.com> - 2017-03-07 10:59 -0800
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 11:06 -0800
Re: RF bipolars RIP Joerg <news@analogconsultants.com> - 2017-03-07 11:16 -0800
Re: RF bipolars RIP "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-03-07 15:11 -0600
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 14:30 -0800
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-07 15:47 -0800
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-07 15:55 -0800
Re: RF bipolars RIP Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2017-03-08 11:50 +0100
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 16:36 -0800
Re: RF bipolars RIP pcdhobbs@gmail.com - 2017-03-08 04:40 -0800
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-08 06:24 -0800
Re: RF bipolars RIP dplatt@coop.radagast.org (Dave Platt) - 2017-03-07 16:55 -0800
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-08 06:40 -0800
Re: RF bipolars RIP Piotr Wyderski <no@mail.com> - 2017-03-09 07:10 +0100
Re: RF bipolars RIP dplatt@coop.radagast.org (Dave Platt) - 2017-03-10 21:32 -0800
Re: RF bipolars RIP "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-03-07 22:57 -0600
Re: RF bipolars RIP, grab em while you can Winfield Hill <hill@rowland.harvard.edu> - 2017-03-09 04:05 -0800
Re: RF bipolars RIP, grab em while you can pcdhobbs@gmail.com - 2017-03-09 04:44 -0800
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-07 17:50 +0000
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 11:08 -0800
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 11:09 -0800
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 14:34 -0500
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 15:40 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-07 20:41 +0000
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 13:08 -0800
Re: RF bipolars RIP "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-03-07 15:14 -0600
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 16:17 -0500
Re: RF bipolars RIP "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-03-07 23:09 -0600
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-07 21:34 -0800
Re: RF bipolars RIP "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-03-08 14:24 -0600
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-08 13:10 -0800
Re: RF bipolars RIP "Michael A. Terrell" <mike.terrell@earthlink.net> - 2017-03-09 14:19 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-09 22:10 +0000
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-10 11:50 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-10 17:27 +0000
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-10 12:52 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-10 19:01 +0000
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-10 15:19 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-10 21:42 +0000
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-10 17:52 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-10 23:38 +0000
Re: RF bipolars RIP pcdhobbs@gmail.com - 2017-03-10 17:38 -0800
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-11 10:23 +0000
Re: RF bipolars RIP pcdhobbs@gmail.com - 2017-03-11 03:30 -0800
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-11 12:50 +0000
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-11 10:49 -0500
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-11 15:55 +0000
Re: RF bipolars RIP "tom" <tmiller11147@verizon.net> - 2017-03-11 11:45 -0500
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-11 16:50 -0500
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 08:58 -0800
Re: RF bipolars RIP Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-11 16:52 -0500
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-10 18:08 -0800
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 07:47 -0800
Re: RF bipolars RIP Cursitor Doom <curd@notformail.com> - 2017-03-11 15:56 +0000
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 09:02 -0800
Re: RF bipolars RIP "Michael A. Terrell" <mike.terrell@earthlink.net> - 2017-03-10 13:28 -0500
Re: RF bipolars RIP pcdhobbs@gmail.com - 2017-03-08 04:35 -0800
Re: RF bipolars RIP Joerg <news@analogconsultants.com> - 2017-03-07 14:05 -0800
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 14:33 -0800
Re: RF bipolars RIP George Herold <gherold@teachspin.com> - 2017-03-07 15:40 -0800
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 16:44 -0800
Re: RF bipolars RIP Mikko OH2HVJ <mikko.syrjalahti@nospam.fi> - 2017-03-08 10:19 +0200
Re: RF bipolars RIP Winfield Hill <hill@rowland.harvard.edu> - 2017-03-08 04:30 -0800
Re: RF bipolars RIP Mikko OH2HVJ <mikko.syrjalahti@nospam.fi> - 2017-03-08 15:38 +0200
Re: RF bipolars RIP Robert Baer <robertbaer@localnet.com> - 2017-03-09 23:50 -0800
Re: RF bipolars RIP pcdhobbs@gmail.com - 2017-03-10 05:39 -0800
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-10 07:15 -0800
Re: RF bipolars RIP "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-03-07 21:55 +0000
Re: RF bipolars RIP Joerg <news@analogconsultants.com> - 2017-03-07 14:10 -0800
Re: RF bipolars RIP John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 14:43 -0800
Re: RF bipolars RIP Tim Wescott <tim@seemywebsite.really> - 2017-03-10 23:54 -0600
Re: RF bipolars RIP pcdhobbs@gmail.com - 2017-03-11 04:32 -0800
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 07:54 -0800
Re: RF bipolars RIP krw@notreal.com - 2017-03-11 11:15 -0500
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 09:17 -0800
Re: RF bipolars RIP "tom" <tmiller11147@verizon.net> - 2017-03-11 15:11 -0500
Re: RF bipolars RIP John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 14:22 -0800
Re: RF bipolars RIP "tom" <tmiller11147@verizon.net> - 2017-03-11 21:11 -0500
Re: RF bipolars RIP krw@notreal.com - 2017-03-11 21:04 -0500
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| From | John Larkin <jjlarkinxyxy@highlandtechnology.com> |
|---|---|
| Date | 2017-03-06 16:51 -0800 |
| Subject | RF bipolars RIP |
| Message-ID | <hf0sbcdr6q698nj4kf0o4afbch9i842oth@4ax.com> |
Looks like NXP is discontinuing their SOT89 RF bipolars, like BFQ149 and BFG31 and such. Bummer. I just designed them in. They have equivalent SOT23s that they rate for 600 milliwatts. SIX HUNDRED MILLIWATTS! Maybe I can get by with some OnSemi 600 MHz SOT89 parts. Kinda slow. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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| From | Winfield Hill <hill@rowland.harvard.edu> |
|---|---|
| Date | 2017-03-06 18:01 -0800 |
| Message-ID | <o9l49201v67@drn.newsguy.com> |
| In reply to | #450540 |
John Larkin wrote...
>
> Looks like NXP is discontinuing ..
Lifetime buys in order.
--
Thanks,
- Win
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| From | Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> |
|---|---|
| Date | 2017-03-07 03:19 +0100 |
| Message-ID | <ei6jlqFg2qcU1@mid.individual.net> |
| In reply to | #450554 |
Am 07.03.2017 um 03:01 schrieb Winfield Hill: > John Larkin wrote... >> >> Looks like NXP is discontinuing .. > > Lifetime buys in order. > > Infineon stil has Sot-89 RF NPNs, but the PNP Situation is ugly. No more easy current source loads at RF. cheers, Gerhard
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| From | John Larkin <jjlarkinxyxy@highlandtechnology.com> |
|---|---|
| Date | 2017-03-06 18:25 -0800 |
| Message-ID | <ee6sbcda71to4jh7vl7f05fjngj8fmjv0u@4ax.com> |
| In reply to | #450558 |
On Tue, 7 Mar 2017 03:19:37 +0100, Gerhard Hoffmann <ghf@hoffmann-hochfrequenz.de> wrote: >Am 07.03.2017 um 03:01 schrieb Winfield Hill: >> John Larkin wrote... >>> >>> Looks like NXP is discontinuing .. >> >> Lifetime buys in order. >> >> >Infineon stil has Sot-89 RF NPNs, but the PNP Situation is ugly. >No more easy current source loads at RF. > >cheers, Gerhard Yeah, I just designed in a SOT89 PNP, BFQ149. Maybe I'll buy 5000 and worry about it later. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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| From | George Herold <gherold@teachspin.com> |
|---|---|
| Date | 2017-03-06 19:03 -0800 |
| Message-ID | <6b873b44-0789-4996-bb53-2b2449af9952@googlegroups.com> |
| In reply to | #450559 |
On Monday, March 6, 2017 at 9:25:55 PM UTC-5, John Larkin wrote: > On Tue, 7 Mar 2017 03:19:37 +0100, Gerhard Hoffmann > <ghf@hoffmann-hochfrequenz.de> wrote: > > >Am 07.03.2017 um 03:01 schrieb Winfield Hill: > >> John Larkin wrote... > >>> > >>> Looks like NXP is discontinuing .. > >> > >> Lifetime buys in order. > >> > >> > >Infineon stil has Sot-89 RF NPNs, but the PNP Situation is ugly. > >No more easy current source loads at RF. > > > >cheers, Gerhard > > Yeah, I just designed in a SOT89 PNP, BFQ149. > > Maybe I'll buy 5000 and worry about it later. > > > -- > > John Larkin Highland Technology, Inc > picosecond timing precision measurement > > jlarkin att highlandtechnology dott com > http://www.highlandtechnology.com Maybe you'll be dead...:^) or maybe someone else will pick-em up? I think we're still buying RF power transistors from Russia or somewhere... ~70 MHz at 1-2W. (70 MHz is my freq, I don't recall where they roll off.) Can't you use a Fet somehow? George H.
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| From | Winfield Hill <hill@rowland.harvard.edu> |
|---|---|
| Date | 2017-03-06 19:11 -0800 |
| Message-ID | <o9l8ck025kn@drn.newsguy.com> |
| In reply to | #450559 |
John Larkin wrote...
> Yeah, I just designed in a SOT89 PNP, BFQ149.
> Maybe I'll buy 5000 and worry about it later.
What's the good NPN complement?
--
Thanks,
- Win
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-03-06 20:40 -0800 |
| Message-ID | <scesbcpvsv9aog4gm4876bp9q5lsb060v7@4ax.com> |
| In reply to | #450570 |
On 6 Mar 2017 19:11:16 -0800, Winfield Hill <hill@rowland.harvard.edu> wrote: >John Larkin wrote... >> Yeah, I just designed in a SOT89 PNP, BFQ149. >> Maybe I'll buy 5000 and worry about it later. > > What's the good NPN complement? BFQ18, still listed as in production. -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-07 07:28 -0800 |
| Message-ID | <ei81tkFollkU1@mid.individual.net> |
| In reply to | #450559 |
On 2017-03-06 18:25, John Larkin wrote: > On Tue, 7 Mar 2017 03:19:37 +0100, Gerhard Hoffmann > <ghf@hoffmann-hochfrequenz.de> wrote: > >> Am 07.03.2017 um 03:01 schrieb Winfield Hill: >>> John Larkin wrote... >>>> >>>> Looks like NXP is discontinuing .. >>> >>> Lifetime buys in order. >>> >>> >> Infineon stil has Sot-89 RF NPNs, but the PNP Situation is ugly. >> No more easy current source loads at RF. >> >> cheers, Gerhard > > Yeah, I just designed in a SOT89 PNP, BFQ149. > > Maybe I'll buy 5000 and worry about it later. > Or maybe buy 20k, at less than $0.50/ea that could be a nice investment if you end up not using them. It is likely that obsolete parts dealers come banging on your door who are then willing to pay 5-10x that money. I just had a situation like that but could not help them because I didn't know any former clients who had stock in the part left. -- Regards, Joerg http://www.analogconsultants.com/
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| From | Winfield Hill <hill@rowland.harvard.edu> |
|---|---|
| Date | 2017-03-06 18:31 -0800 |
| Message-ID | <o9l61s0221m@drn.newsguy.com> |
| In reply to | #450558 |
Gerhard Hoffmann wrote...
>
>Am 07.03.2017 um 03:01 schrieb Winfield Hill:
>> John Larkin wrote...
>>>
>>> Looks like NXP is discontinuing ..
>>
>> Lifetime buys in order.
>>
> Infineon still has Sot-89 RF NPNs, but the PNP
> Situation is ugly. No more easy current
> source loads at RF.
What about Diodes / Zetex parts?
--
Thanks,
- Win
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-03-06 20:44 -0800 |
| Message-ID | <ceesbc1dau6i0kfeggv8f1cqbpka6cf98u@4ax.com> |
| In reply to | #450569 |
On 6 Mar 2017 18:31:24 -0800, Winfield Hill <hill@rowland.harvard.edu> wrote: >Gerhard Hoffmann wrote... >> >>Am 07.03.2017 um 03:01 schrieb Winfield Hill: >>> John Larkin wrote... >>>> >>>> Looks like NXP is discontinuing .. >>> >>> Lifetime buys in order. >>> >> Infineon still has Sot-89 RF NPNs, but the PNP >> Situation is ugly. No more easy current >> source loads at RF. > > What about Diodes / Zetex parts? I spent the afternoon looking. All the available SOT89s are really slow. I need to dissipate 600 mW in the PNP, so the SOT23 and such are out. Same issue as the phemts: fast discretes are disappearing. -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> |
|---|---|
| Date | 2017-03-07 10:17 -0500 |
| Message-ID | <xZadnVJBO5i5UiPFnZ2dnUU7-LHNnZ2d@supernews.com> |
| In reply to | #450577 |
On 03/06/2017 11:44 PM, John Larkin wrote: > On 6 Mar 2017 18:31:24 -0800, Winfield Hill <hill@rowland.harvard.edu> > wrote: > >> Gerhard Hoffmann wrote... >>> >>> Am 07.03.2017 um 03:01 schrieb Winfield Hill: >>>> John Larkin wrote... >>>>> >>>>> Looks like NXP is discontinuing .. >>>> >>>> Lifetime buys in order. >>>> >>> Infineon still has Sot-89 RF NPNs, but the PNP >>> Situation is ugly. No more easy current >>> source loads at RF. >> >> What about Diodes / Zetex parts? > > I spent the afternoon looking. All the available SOT89s are really > slow. I need to dissipate 600 mW in the PNP, so the SOT23 and such are > out. So one would have to parallel BFT93s, then. Blech. > > Same issue as the phemts: fast discretes are disappearing. > > I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, BFP640s, BFP650s, BFU520As, and a few others that are still apparently in production. Ties up a few $k in inventory, but preserves freedom of action and possibly future competitive advantage. Inconvenient. 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
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-03-07 08:08 -0800 |
| Message-ID | <4jmtbc5cbo1okcsgechgv4m7bp3lav9ht1@4ax.com> |
| In reply to | #450622 |
On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >On 03/06/2017 11:44 PM, John Larkin wrote: >> On 6 Mar 2017 18:31:24 -0800, Winfield Hill <hill@rowland.harvard.edu> >> wrote: >> >>> Gerhard Hoffmann wrote... >>>> >>>> Am 07.03.2017 um 03:01 schrieb Winfield Hill: >>>>> John Larkin wrote... >>>>>> >>>>>> Looks like NXP is discontinuing .. >>>>> >>>>> Lifetime buys in order. >>>>> >>>> Infineon still has Sot-89 RF NPNs, but the PNP >>>> Situation is ugly. No more easy current >>>> source loads at RF. >>> >>> What about Diodes / Zetex parts? >> >> I spent the afternoon looking. All the available SOT89s are really >> slow. I need to dissipate 600 mW in the PNP, so the SOT23 and such are >> out. > >So one would have to parallel BFT93s, then. Blech. Yes. And balance the currents. And pray they don't oscillate. > >> >> Same issue as the phemts: fast discretes are disappearing. >> >> > >I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >BFP640s, BFP650s, BFU520As, and a few others that are still apparently >in production. Ties up a few $k in inventory, but preserves freedom of >action and possibly future competitive advantage. It's rude of people to not make p-channel phemts. -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> |
|---|---|
| Date | 2017-03-07 12:15 -0500 |
| Message-ID | <-ZmdnV-AmY1SdyPFnZ2dnUU7-XXNnZ2d@supernews.com> |
| In reply to | #450628 |
On 03/07/2017 11:08 AM, John Larkin wrote: > On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 03/06/2017 11:44 PM, John Larkin wrote: >>> On 6 Mar 2017 18:31:24 -0800, Winfield Hill <hill@rowland.harvard.edu> >>> wrote: >>> >>>> Gerhard Hoffmann wrote... >>>>> >>>>> Am 07.03.2017 um 03:01 schrieb Winfield Hill: >>>>>> John Larkin wrote... >>>>>>> >>>>>>> Looks like NXP is discontinuing .. >>>>>> >>>>>> Lifetime buys in order. >>>>>> >>>>> Infineon still has Sot-89 RF NPNs, but the PNP >>>>> Situation is ugly. No more easy current >>>>> source loads at RF. >>>> >>>> What about Diodes / Zetex parts? >>> >>> I spent the afternoon looking. All the available SOT89s are really >>> slow. I need to dissipate 600 mW in the PNP, so the SOT23 and such are >>> out. >> >> So one would have to parallel BFT93s, then. Blech. > > Yes. And balance the currents. And pray they don't oscillate. One approach when you don't need wide range fast slewing is an NPN connected as a pseudo-inductor (resistor from C-B, cap from B-E). It's good for stiffening PNP current sources. Of course the limited slew range probably leaves out every single one of your applications. :( > >> >>> >>> Same issue as the phemts: fast discretes are disappearing. >>> >>> >> >> I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >> LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >> BFP640s, BFP650s, BFU520As, and a few others that are still apparently >> in production. Ties up a few $k in inventory, but preserves freedom of >> action and possibly future competitive advantage. > > It's rude of people to not make p-channel phemts. Tubes have a similar problem, for similar reasons. ;) 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
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| From | John Larkin <jjlarkin@highlandtechnology.com> |
|---|---|
| Date | 2017-03-07 09:30 -0800 |
| Message-ID | <jfrtbc5jjniiqpk5ns0kmv4cc8vt0437ud@4ax.com> |
| In reply to | #450635 |
On Tue, 7 Mar 2017 12:15:59 -0500, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >On 03/07/2017 11:08 AM, John Larkin wrote: >> On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> On 03/06/2017 11:44 PM, John Larkin wrote: >>>> On 6 Mar 2017 18:31:24 -0800, Winfield Hill <hill@rowland.harvard.edu> >>>> wrote: >>>> >>>>> Gerhard Hoffmann wrote... >>>>>> >>>>>> Am 07.03.2017 um 03:01 schrieb Winfield Hill: >>>>>>> John Larkin wrote... >>>>>>>> >>>>>>>> Looks like NXP is discontinuing .. >>>>>>> >>>>>>> Lifetime buys in order. >>>>>>> >>>>>> Infineon still has Sot-89 RF NPNs, but the PNP >>>>>> Situation is ugly. No more easy current >>>>>> source loads at RF. >>>>> >>>>> What about Diodes / Zetex parts? >>>> >>>> I spent the afternoon looking. All the available SOT89s are really >>>> slow. I need to dissipate 600 mW in the PNP, so the SOT23 and such are >>>> out. >>> >>> So one would have to parallel BFT93s, then. Blech. >> >> Yes. And balance the currents. And pray they don't oscillate. > >One approach when you don't need wide range fast slewing OK, you can stop right there! is an NPN >connected as a pseudo-inductor (resistor from C-B, cap from B-E). It's >good for stiffening PNP current sources. Of course the limited slew >range probably leaves out every single one of your applications. :( > >> >>> >>>> >>>> Same issue as the phemts: fast discretes are disappearing. >>>> >>>> >>> >>> I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >>> LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >>> BFP640s, BFP650s, BFU520As, and a few others that are still apparently >>> in production. Ties up a few $k in inventory, but preserves freedom of >>> action and possibly future competitive advantage. >> >> It's rude of people to not make p-channel phemts. > >Tubes have a similar problem, for similar reasons. ;) > >Cheers > >Phil Hobbs -- John Larkin Highland Technology, Inc lunatic fringe electronics
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-07 09:33 -0800 |
| Message-ID | <ei896eFq5ilU1@mid.individual.net> |
| In reply to | #450635 |
On 2017-03-07 09:15, Phil Hobbs wrote: > On 03/07/2017 11:08 AM, John Larkin wrote: >> On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> On 03/06/2017 11:44 PM, John Larkin wrote: [...] >>>> Same issue as the phemts: fast discretes are disappearing. >>>> >>>> >>> >>> I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >>> LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >>> BFP640s, BFP650s, BFU520As, and a few others that are still apparently >>> in production. Ties up a few $k in inventory, but preserves freedom of >>> action and possibly future competitive advantage. >> >> It's rude of people to not make p-channel phemts. > > Tubes have a similar problem, for similar reasons. ;) > However, tubes have a staunch constituency and the Russians and Chinese have figured out how to cash in. http://www.thetubestore.com/Tubes/6L6-5881-Tube-Types/Svetlana-6L6GC Even very cool looking ones: http://psvanetube.com/wordpress/store/products/treasure-globe-6sn7-se-pair-gf-limited-special-edition/ I had a bet going with a boss in the 80's that our ultrasound Doppler units could have already been built very economically in WW-II and before, with tubes. He didn't believe it. When I gradually retire I could build such a machine. Got the tubes, sockets and stuff. Problem is, neither of us has cardiovascular issues so we don't really need it. Also, the only way to build such a device would be with highly polished wood and brass as an enclosure. -- Regards, Joerg http://www.analogconsultants.com/
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| From | Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> |
|---|---|
| Date | 2017-03-07 12:44 -0500 |
| Message-ID | <e6cf64da-cdcb-7b6e-5ea4-d77bd53622ed@electrooptical.net> |
| In reply to | #450637 |
On 03/07/2017 12:33 PM, Joerg wrote: > On 2017-03-07 09:15, Phil Hobbs wrote: >> On 03/07/2017 11:08 AM, John Larkin wrote: >>> On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> On 03/06/2017 11:44 PM, John Larkin wrote: > > > [...] > > >>>>> Same issue as the phemts: fast discretes are disappearing. >>>>> >>>>> >>>> >>>> I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >>>> LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >>>> BFP640s, BFP650s, BFU520As, and a few others that are still apparently >>>> in production. Ties up a few $k in inventory, but preserves freedom of >>>> action and possibly future competitive advantage. >>> >>> It's rude of people to not make p-channel phemts. >> >> Tubes have a similar problem, for similar reasons. ;) >> > > However, tubes have a staunch constituency and the Russians and Chinese > have figured out how to cash in. I don't think they've figured out how to make P-channel ones yet, though. ;) > > http://www.thetubestore.com/Tubes/6L6-5881-Tube-Types/Svetlana-6L6GC > > Even very cool looking ones: > > http://psvanetube.com/wordpress/store/products/treasure-globe-6sn7-se-pair-gf-limited-special-edition/ > > > I had a bet going with a boss in the 80's that our ultrasound Doppler > units could have already been built very economically in WW-II and > before, with tubes. He didn't believe it. When I gradually retire I > could build such a machine. Got the tubes, sockets and stuff. Problem > is, neither of us has cardiovascular issues so we don't really need it. > Also, the only way to build such a device would be with highly polished > wood and brass as an enclosure. When I was at IBM, I used an 811A to switch bias onto the grids of a drift chamber. No semiconductor could come near its performance for that job. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
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| From | Cursitor Doom <curd@notformail.com> |
|---|---|
| Date | 2017-03-07 17:53 +0000 |
| Message-ID | <o9ms36$to3$3@dont-email.me> |
| In reply to | #450637 |
On Tue, 07 Mar 2017 09:33:07 -0800, Joerg wrote: > However, tubes have a staunch constituency and the Russians and Chinese > have figured out how to cash in. > Yes, the Russians make some killer tubes, god bless 'em and good luck to them for their efforts. Not sure about Chinese ones, though. I still don't trust anything made in China.
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-07 10:59 -0800 |
| Message-ID | <ei8e97Fr72qU2@mid.individual.net> |
| In reply to | #450642 |
On 2017-03-07 09:53, Cursitor Doom wrote: > On Tue, 07 Mar 2017 09:33:07 -0800, Joerg wrote: > >> However, tubes have a staunch constituency and the Russians and Chinese >> have figured out how to cash in. >> > > Yes, the Russians make some killer tubes, god bless 'em and good luck to > them for their efforts. Not sure about Chinese ones, though. I still > don't trust anything made in China. > Some electronics from China are of good quality. Some of the dealers there are less than honest though. I just had one who promised twice to send a warranty replacement, never did, and doesn't respond to emails. I'll have to check how long one can place a credit card payment in dispute, just out of principle. -- Regards, Joerg http://www.analogconsultants.com/
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| From | John Larkin <jjlarkinxyxy@highlandtechnology.com> |
|---|---|
| Date | 2017-03-07 11:06 -0800 |
| Message-ID | <g21ubcdtme1m5sjpa6bfk6motguoqpoiql@4ax.com> |
| In reply to | #450637 |
On Tue, 07 Mar 2017 09:33:07 -0800, Joerg <news@analogconsultants.com> wrote: >On 2017-03-07 09:15, Phil Hobbs wrote: >> On 03/07/2017 11:08 AM, John Larkin wrote: >>> On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> On 03/06/2017 11:44 PM, John Larkin wrote: > > >[...] > > >>>>> Same issue as the phemts: fast discretes are disappearing. >>>>> >>>>> >>>> >>>> I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >>>> LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >>>> BFP640s, BFP650s, BFU520As, and a few others that are still apparently >>>> in production. Ties up a few $k in inventory, but preserves freedom of >>>> action and possibly future competitive advantage. >>> >>> It's rude of people to not make p-channel phemts. >> >> Tubes have a similar problem, for similar reasons. ;) >> > >However, tubes have a staunch constituency and the Russians and Chinese >have figured out how to cash in. > >http://www.thetubestore.com/Tubes/6L6-5881-Tube-Types/Svetlana-6L6GC > >Even very cool looking ones: > >http://psvanetube.com/wordpress/store/products/treasure-globe-6sn7-se-pair-gf-limited-special-edition/ > >I had a bet going with a boss in the 80's that our ultrasound Doppler >units could have already been built very economically in WW-II and >before, with tubes. He didn't believe it. When I gradually retire I >could build such a machine. Got the tubes, sockets and stuff. Problem >is, neither of us has cardiovascular issues so we don't really need it. >Also, the only way to build such a device would be with highly polished >wood and brass as an enclosure. Black wrinkle finish, engraved and filled lettering. Geez, there was some ugly gear back when. The Tek 530-series scopes were a stunning style breakthrough. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
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| From | Joerg <news@analogconsultants.com> |
|---|---|
| Date | 2017-03-07 11:16 -0800 |
| Message-ID | <ei8f92FreljU1@mid.individual.net> |
| In reply to | #450662 |
On 2017-03-07 11:06, John Larkin wrote: > On Tue, 07 Mar 2017 09:33:07 -0800, Joerg <news@analogconsultants.com> > wrote: > >> On 2017-03-07 09:15, Phil Hobbs wrote: >>> On 03/07/2017 11:08 AM, John Larkin wrote: >>>> On Tue, 7 Mar 2017 10:17:56 -0500, Phil Hobbs >>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>> >>>>> On 03/06/2017 11:44 PM, John Larkin wrote: >> >> >> [...] >> >> >>>>>> Same issue as the phemts: fast discretes are disappearing. >>>>>> >>>>>> >>>>> >>>>> I ordered a reel of BFG403s (basically a 17-GHz BFT25A), which are on >>>>> LTB, and am plotting to get some SKY65050s, ATF38143s, ATF55143s, >>>>> BFP640s, BFP650s, BFU520As, and a few others that are still apparently >>>>> in production. Ties up a few $k in inventory, but preserves freedom of >>>>> action and possibly future competitive advantage. >>>> >>>> It's rude of people to not make p-channel phemts. >>> >>> Tubes have a similar problem, for similar reasons. ;) >>> >> >> However, tubes have a staunch constituency and the Russians and Chinese >> have figured out how to cash in. >> >> http://www.thetubestore.com/Tubes/6L6-5881-Tube-Types/Svetlana-6L6GC >> >> Even very cool looking ones: >> >> http://psvanetube.com/wordpress/store/products/treasure-globe-6sn7-se-pair-gf-limited-special-edition/ >> >> I had a bet going with a boss in the 80's that our ultrasound Doppler >> units could have already been built very economically in WW-II and >> before, with tubes. He didn't believe it. When I gradually retire I >> could build such a machine. Got the tubes, sockets and stuff. Problem >> is, neither of us has cardiovascular issues so we don't really need it. >> Also, the only way to build such a device would be with highly polished >> wood and brass as an enclosure. > > Black wrinkle finish, engraved and filled lettering. > Or rhinestone lettering :-) > Geez, there was some ugly gear back when. The Tek 530-series scopes > were a stunning style breakthrough. > Aren't those with the tantalum issues? I don't mind an ugly unit that works for decades. Also, my 7704A ain't that bad-looking. Now the power supply goes zzzt at times but it's around 30 years old. -- Regards, Joerg http://www.analogconsultants.com/
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