Microwave diode?
DaveC
20-plus years old and obsolete. Looking for current equivalent, possibly (but
not necessarily) smt.
Are these useable in place of a 1N21B for 2.4 GHz detection?:
Suggestions welcome.
Thanks,
--
DaveC
m...@bogusdomain.net
This is an invalid return address
Please reply in the news group
John Larkin
>Have simple detector circuit that specifies 1N21B diode. That diode is
>20-plus years old and obsolete. Looking for current equivalent, possibly (but
>not necessarily) smt.
>
>Are these useable in place of a 1N21B for 2.4 GHz detection?:
>
><http://tinyurl.com/6g62bu>
>
><http://tinyurl.com/62fqnv>
>
>Suggestions welcome.
>
>Thanks,
Those look good. Skyworks has some really nice low-barrier Schottky
diodes. And they have a fabulous sample kit of schottkies and
varactors, lots of parts.
Go for "low barrier" parts for unbiased low-level detection.
The best detectors are probably germanium back diodes, but expensive.
Several semi companies now make active detectors... LTC, ADI.
John
ian field
"DaveC" <m...@bogusdomain.net> wrote in message
news:0001HW.C5596B30...@news.sf.sbcglobal.net...
Depends which "C-band" those spec sheets refer to: IEEE C-band is about 4 -
8Ghz, NATO C-band is about 0.5 - 1Ghz.
Phil Hobbs
Cheers,
Phil Hobbs
Eeyore
DaveC wrote:
> Have simple detector circuit that specifies 1N21B diode. That diode is
> 20-plus years old and obsolete. Looking for current equivalent, possibly (but
> not necessarily) smt.
>
> Are these useable in place of a 1N21B for 2.4 GHz detection?:
>
> <http://tinyurl.com/6g62bu>
>
> <http://tinyurl.com/62fqnv>
"1N23B is a point contact silicon diode. For the ages that was the
closest thing to Shottkey and the diode for microwave. In a lot of
old hardware the newer shottkey diodes will easily replace the
1N23 series assuming no mechanical limitations.
FYI: the suffix specificied specific sorting of 1n23 for noise,
working frequency and threshold voltage."
http://newsgroups.derkeiler.com/Archive/Rec/rec.radio.amateur.homebrew/2005-10/msg00024.html
To compare 1N21 to 1N23 go here and download the data.
http://www.alldatasheet.com/datasheet-pdf/pdf/121950/ETC/1N23B.html
Graham
alt group trimmed
a7yvm1...@netzero.com
1N5711. Worked in my decades-old 1L20 spectrum analyzer's front-end
mixer.
Eeyore
Eeyore wrote:
Data on your first part here
http://sigma.octopart.com/12153/datasheet/Avago-HSMS-2860-TR1G.pdf
Not sure what the suffix means but there's a load of them here.
http://www.datasheetarchive.com/HSMS2860-datasheet.html
Graham
ian field
<a7yvm1...@netzero.com> wrote in message
news:114cf7ed-2403-4fbf...@o2g2000yqd.googlegroups.com...
Is that similar to the 1N6264 ?
Eeyore
a7yvm1...@netzero.com wrote:
> On Dec 1, 1:21 pm, DaveC <m...@bogusdomain.net> wrote:
> > Have simple detector circuit that specifies 1N21B diode. That diode is
> > 20-plus years old and obsolete. Looking for current equivalent, possibly (but
> > not necessarily) smt.
> >
> > Are these useable in place of a 1N21B for 2.4 GHz detection?:
> >
> > <http://tinyurl.com/6g62bu>
> >
> > <http://tinyurl.com/62fqnv>
>
> 1N5711. Worked in my decades-old 1L20 spectrum analyzer's front-end
> mixer.
Someone else who doesn't know what a thread is thanks to Google ! Would you mind
learning please ?
Graham
Eeyore
John Larkin wrote:
There was a thread about this a few months back in s.e.d IIRC.
Graham
Alt group trimmed
John Larkin
That's a big-junction, high-barrier part, OK for a UHF mixer. But with
roughly 1.5 pF of zero-bias capacitance, it's not ideal as a detector
at 2.4 GHz.
John
Eeyore
John Larkin wrote:
> DaveC <m...@bogusdomain.net> wrote:
>
> >Have simple detector circuit that specifies 1N21B diode. That diode is
> >20-plus years old and obsolete. Looking for current equivalent, possibly (but
> >not necessarily) smt.
> >
> >Are these useable in place of a 1N21B for 2.4 GHz detection?:
> >
> ><http://tinyurl.com/6g62bu>
> >
> ><http://tinyurl.com/62fqnv>
>
> Those look good. Skyworks has some really nice low-barrier Schottky
> diodes. And they have a fabulous sample kit of schottkies and
> varactors, lots of parts.
>
> Go for "low barrier" parts for unbiased low-level detection.
>
> The best detectors are probably germanium back diodes, but expensive.
>
> Several semi companies now make active detectors... LTC, ADI.
Any idea how well 0.35pF compares with a point contact type ? Googling 1N23B
brings up plenty of data including that for the 1N21B but I've yet to see any
capacitance figures.
"These point contact "cat's whisker" devices, are still made occasionally because
of their very small capacitance. As it was discovered early on, they are highly
useful in high frequency electronics."
http://www.oddmix.com/tech/cr_from_crysdets_todiodes.html
Graham
ian field
"John Larkin" <jjla...@highNOTlandTHIStechnologyPART.com> wrote in message
news:8ph8j49p9u5tgle8k...@4ax.com...
My question was off topic - I simply wondered if the two were similar.
John Larkin
<gangprob...@ntlworld.com> wrote:
Sorry, wrong guy.
John
Wimpie
Hello Dave,
Try bat15 (comes in various packages, single,dual, quad), low
capacitance (0.35pF at 0V bias, that is far better then the general
purpose hybrid schottky rectifiers, the specify them at, for example,
-0.5V). Video resistance of about 100 kOhm, so you can use it as a
zero bias detector when loaded with 1M Ohm or more.
When you want to detect higher voltages, try bat62. This one has some
more capacitance, but still a fast diode, with 40V (yes, 40V) reverse
voltage. Video resistance is also about 100 kOhms,
When you want high video bandwidth, you should bias them or use
special zero bias detector diodes with low video resistance.
Best regards,
Wim
PA3DJS
www.tetech.nl
Leave out abc, and the mail is OK.
Eeyore
Eeyore wrote:
Sorry reply to wrong post.
Graham
o...@uakron.edu
specified for?
Shfmicro sells diodes in one offs.
Steve Roberts
Rene Tschaggelar
Almost as important as the capacitance, which is
covered by the frequency range anyway, ist the
case. It should suit the application, meaning the
geometry of the mounting. The manufacturers divide
into mixer diodes and detector diodes. The detector
diodes are specified in terms of mV/uW together
with a loading. The loading is connected to the
video bandwidth. The higher the bandwidth the
lower the load. I'm not too familiar with 2.4GHz,
but assume few kOhms would be usual. There are
different sort of bias to achieve a high
sensitivity. RF of the same frequency, but adjustable
phase, DC, none. This usually is given by the setup.
I wasn't yet able to figure out what happens
when a zerobias detector is suddenly biased, or
whether a DC bias detector can be RF biased.
Rene
Eeyore
Rene Tschaggelar wrote:
You know, I picked up all this info when the father of a good friend of mine died. The
son let me take some books of his. His father was Anthony Tucker who was a fighter
pilot in WW2 in N.Africa.
Later he became the Science Editor for the Guardian (UK) newspaper. He was one hell of
a smart guy. I shall never forget him. I even lived with the family as a lodger for a
while which is where I picked up most of my environmental clues. He is buried in the
grounds of St Albans Cathedral.
Graham
DaveC
The project is this:
<http://www.atvinderby.co.uk/2.4Ghz_SWR_Meter.htm>
To the person asking about form-factor: there isn't any. Well, there is
concern about strain relief, so if I choose an smt part it should be soldered
to a speck of pcb to provide relief.
I looked at the BAT62 part; the datasheets say "up to GHz frequencies", but
no specified bw:
<http://www.datasheetcatalog.com/datasheets_pdf/B/A/T/6/BAT62-03W.shtml>
Is this a good stand-in for the 1N21B?
Wimpie
DaveC ha escrito:
Hello,
As a zero bias detector, up to 1 GHz I prefer BAT62 over 1N5711.
Capacitance is 0.65 pF max, while for 1n5711 it 2 pF (I thought).
When you make sure DC load is 1 Mohm or more, you retrieve over 80% of
detected EMK.
Do not use BAT62 in a mixer or high bias situation as the intrinsic
resistance is rather high. This intrinsic resistance (200 Ohms)
limits its usable frequency despite the low capacitance. When voltage
to be detected is low (max 2V RF amplitude), a better choice is BAT15
(cap < 0.35pF, so it is closer to 1N21). Though BAT15 is a mixer diode
(12 GHz), video resistance is not that high (100 kOhm).
When you make sure the load resistance >> video resistance (that is
the diode resistance at zero bias), sensitivity is as good as
sensitivity of special detector diodes up to many GHz. When you match
the diode, sensitivity is really high.
The advantage of the special very low barrier detector diodes is that
you can use them at zero bias with moderate load. So you don't need a
high impedance input. Of course you can bias a normal diode to get
low video resistance, but than DC output measurement becomes more
difficult because of thermal aspects.
Best regards,
Wim
PA3DJS
www.tetech.nl
remove abc and you have a valid mail address.
ne...@picaxe.us
>Have simple detector circuit that specifies 1N21B diode. That diode is
>20-plus years old and obsolete. Looking for current equivalent, possibly (but
>not necessarily) smt.
>
>Are these useable in place of a 1N21B for 2.4 GHz detection?:
>
><http://tinyurl.com/6g62bu>
>
><http://tinyurl.com/62fqnv>
>
>Suggestions welcome.
>
>Thanks,
How much is a 1n21 or 1n23 (wrapped in the original foil) worth these
days? I probably still have a couple in the parts cabinet that
contains the germanium transistors.
John
o...@uakron.edu
google " w1ghz power meter"
or http://www.w1ghz.org/QEX/A_UHF+_VSWR_Bridge.pdf
Steve Roberts
JosephKK
Current production 1N23 may be Silicon Schottky but the originals are
Germanium point contact. Do you remember a guy advertising as "Oliver
Germanium"? Those old 1960's and 1970's ads were memorable for that.
John Larkin
wrote:
1N23 is still manufactured as a silicon point-contact diode...
http://www.digchip.com/datasheets/download_datasheet.php?id=14882&part-number=1N23
and I believe it always was.
John
JosephKK
And i suppose that 2n27 and 2n107 and 2n176 transistors were not
Germanium transistors as well in the early days.
See:
http://semiconductormuseum.com/PhotoGallery/PhotoGallery_2N27.htm
http://semiconductormuseum.com/PhotoGallery/PhotoGallery_2N107.htm
http://semiconductormuseum.com/PhotoGallery/PhotoGallery_Motorola_2N176.htm
And even the venerated (in some places) CK722 is germanium:
History is.
Early 1n23 devices were Germanium. Current devices not so much.
John Larkin
wrote:
Excuse me, but transistors are not diodes.
"...but all of the cartriges manufactured commercially for mixers have
used silicon crystals."
- MIT RadLab vol 15, p 7, published in 1948. Silicon was preferred to
germanium for radar first mixers for its superior burnout
resistance... the mixers were in the same waveguide structure as
transmit magnetrons running in the hundreds of kilowatts pulse power,
sometimes megawatts.
Table D-1 lists the common microwave mixer cartrige diodes, including
1N21, 1N23, 1N25, and 1N28. Silicon.
>
>Early 1n23 devices were Germanium. Current devices not so much.
>
Wrong. Silicon point-contact diodes were in use as hf detectors from
about 1925.
John
NoSPAM
news:h54sj4l1fhi1t04ae...@4ax.com...
Actually,the 1N21 and 1N23 diodes were silicon from the beginning. Your
arguments about germanium might sound logical, but they have nothing to do
with the history of silicon devices being used for microwave detectors and
mixers. In fact, silicon point-contact diodes were in use from the
earliest days of radio - even predating the invention of the vacuum tube.
An article published in THE Bent [a quarterly publication of Tau Beta Pi -
the national engineering honor society], by Dr. Frederick Seitz goes into
the early history of silicon devices. A copy of this article,The Tangled
Prelude to the Age of Silicon Electronics,.may be found at:
http://sco.theporch.com:8000/reguser/archives/BOATANCHORS/library/the.silicon.age.begins.txt.
I do ask that the copyright of this article be respected. To read the
article, you will need to register as a user at
http://sco.theporch.com:8000/.
Dr. Barry L. Ornitz [SC A '65]
Jim Thompson
On Tue, 9 Dec 2008 11:28:09 -0500, "NoSPAM" <unk...@nospam.org>
wrote:
[snip]
>
>Actually,the 1N21 and 1N23 diodes were silicon from the beginning. Your
>arguments about germanium might sound logical, but they have nothing to do
>with the history of silicon devices being used for microwave detectors and
>mixers. In fact, silicon point-contact diodes were in use from the
>earliest days of radio - even predating the invention of the vacuum tube.
>
>An article published in THE Bent [a quarterly publication of Tau Beta Pi -
>the national engineering honor society], by Dr. Frederick Seitz goes into
>the early history of silicon devices. A copy of this article,The Tangled
>Prelude to the Age of Silicon Electronics,.may be found at:
>http://sco.theporch.com:8000/reguser/archives/BOATANCHORS/library/the.silicon.age.begins.txt.
>
>I do ask that the copyright of this article be respected. To read the
>article, you will need to register as a user at
>http://sco.theporch.com:8000/.
>
> Dr. Barry L. Ornitz [SC A '65]
Registered, received "confirmation", sent it back as requested,
received E-mail "Registration Successful".
(1) URL provided in "Registration Successful" E-mail comes up as
"Unable to Connect".
(2) Your link to paper (above) declares only LIST registrants can
access :-(
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine Sometimes I even put it in the food
JosephKK
wrote:
>"JosephKK" <quiett...@yahoo.com> wrote in message
OK. I have not been able to properly support my case. What issue of
the Bent is it from? I expect to be able to access it directly.
NoSPAM
>>An article published in THE Bent [a quarterly publication of Tau Beta
>>Pi -
>>the national engineering honor society], by Dr. Frederick Seitz goes into
>>the early history of silicon devices. A copy of this article,The Tangled
>>Prelude to the Age of Silicon Electronics,.may be found at:
>>http://sco.theporch.com:8000/reguser/archives/BOATANCHORS/library/the.silicon.age.begins.txt.
>>
>>I do ask that the copyright of this article be respected. To read the
>>article, you will need to register as a user at
>>http://sco.theporch.com:8000/.
>>
>> Dr. Barry L. Ornitz [SC A '65]
>
> OK. I have not been able to properly support my case. What issue of
> the Bent is it from? I expect to be able to access it directly.
I do not bother to keep old copies of The Bent, but I know this article was
published in 1996. With only four issues a year, this should narrow your
search.
Barry
John Larkin
wrote:
Support your case? That 1N23's were originally germanium diodes?
John
JosephKK
wrote:
Thanks and drat. I no longer have any that old. Off to the local
uni. From what i have found though it appears that John Larkin is
correct; 1n2x series were silicon schottky from the start. I had not
thought that they could refine silicon well enough back then.
I think i will have to ask them to provide my subscription in PDF form
instead. Ca theta 92 (but i was middle age by then).
JosephKK
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:
What i have been able to find indicates that there really were silicon
diodes in 1948, including schottky types. It seems that you are
correct.
John Larkin
wrote:
Get a copy of the RadLab book "Crystal Rectifiers." They show up on
ebay. It's shocking how much they understood about semiconductor
theory in the early 1940's. Somewhere they casually mention that "a
semiconductor triode should be possible."
Once when I was a kid, I had lunch with Walter Brattain, one of the
inventors of the transistor. Very nice guy.
John
Jan Panteltje
<jjSNIP...@highTHISlandtechnology.com> wrote in
<hif6k45um7sf5qbba...@4ax.com>:
>Get a copy of the RadLab book "Crystal Rectifiers." They show up on
>ebay. It's shocking how much they understood about semiconductor
>theory in the early 1940's. Somewhere they casually mention that "a
>semiconductor triode should be possible."
>
>Once when I was a kid, I had lunch with Walter Brattain, one of the
>inventors of the transistor. Very nice guy.
>
>John
So you told him about that book right? ;-)
JosephKK
I won't touch ebay. Nor paypal. Too much spam pretending to be them.
I offer a deal, you buy and reship to me. i pay all documented costs
and a small premium to help make it worth your while. Other regulars
here are offered the same deal.
John Larkin
He got his Nobel in 1956. I had lunch with him in, maybe, 1964. I
didn't discover the RadLab books until a couple of years later.
John