Re: HP8405A - Uncommon component failure?
Silver mica caps suffer from silver migration. They develop leakage, until they short out. They cause a lot of noise problems in older radios, in IF transformers as they arc along the tips of the migrated silver. It is so prevalent that it is named 'Silver Mica Disease' among people who collect old radios.
One TV transmitter I worked on used a large silver mica capacitor that cost over $500 that would die every few years, and often with a loud bang as it took out the power supply to that 4CX250 driver stage.
Michael A. Terrell
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-----Original Message----- From: Scott McGrath <scott@...>
Sent: Oct 30, 2018 10:20 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP8405A - Uncommon component failure?
Ive seen those components fail before but usually with those failure tends to be mechanical rather than electrical.
Thermal cycling, mounting stress, defect in bonding leads etc. as they usually fail ‘open’ instead of short.
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Re: 5370B problem. -5 V rail not working, and 7 A fuse in -10 V unregulated supply blown.
Dr. David Kirkby from Kirkby Microwave Ltd
Only the earlier 5370As used that ROM slot.? The ROM is on the CPU board in later 'A's and 'B's.
Cheers. Do you know anything about the memory expansion board? Is that another left-over from the older A version?
Dave
Dr David Kirkby Ph.D C.Eng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD, Essex, CM3 6DT, United Kingdom.
Registered in England and Wales as company number 08914892
Tel 01621-680100 / +44 1621-680100
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Re: 5370B problem. -5 V rail not working, and 7 A fuse in -10 V unregulated supply blown.
Only the earlier 5370As used that ROM slot.? The ROM is on the CPU board in later 'A's and 'B's.
On Tue, Oct 30, 2018 at 9:48 AM Dr. David Kirkby from Kirkby Microwave Ltd < drkirkby@...> wrote: I have a 5370B which I bought from eBay with supposedly error 02, which is an overflow and user error. However,? on opening it up I can see the problem is more than that, because one of the 7 A fuses in the power supply board has gone, and the -5.2 V supply is not present. The fuse looks like the cap is actually pulled off of it, so maybe its a physical problem rather than the element is blown.
I am going to order a replacement fuse as I have nothing like this, but while I am waiting for it to appear, is anyone aware of any common faults on this? Also, I have 4 sets of edge connectors with no boards in them. 1) XA14 service aid 2) XA13 memory option 3) XA12 ROM 4) XA12 Spare the third one in that list, XA12 ROM, sounds as though it should be present, but I have no idea if that's the case. I do have another 5370B here, so swapping/checking parts is in "theory" easy, but the thing is buried under so much other test equipment that getting it out is no easy task. Dave ? -- Dr David Kirkby Ph.D C.Eng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD, Essex, CM3 6DT, United Kingdom.
Registered in England and Wales as company number 08914892
Tel 01621-680100 / +44 1621-680100
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5370B problem. -5 V rail not working, and 7 A fuse in -10 V unregulated supply blown.
Dr. David Kirkby from Kirkby Microwave Ltd
I have a 5370B which I bought from eBay with supposedly error 02, which is an overflow and user error. However,? on opening it up I can see the problem is more than that, because one of the 7 A fuses in the power supply board has gone, and the -5.2 V supply is not present. The fuse looks like the cap is actually pulled off of it, so maybe its a physical problem rather than the element is blown.
I am going to order a replacement fuse as I have nothing like this, but while I am waiting for it to appear, is anyone aware of any common faults on this? Also, I have 4 sets of edge connectors with no boards in them. 1) XA14 service aid 2) XA13 memory option 3) XA12 ROM 4) XA12 Spare the third one in that list, XA12 ROM, sounds as though it should be present, but I have no idea if that's the case. I do have another 5370B here, so swapping/checking parts is in "theory" easy, but the thing is buried under so much other test equipment that getting it out is no easy task. Dave ? -- Dr David Kirkby Ph.D C.Eng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD, Essex, CM3 6DT, United Kingdom.
Registered in England and Wales as company number 08914892
Tel 01621-680100 / +44 1621-680100
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Re: HP85050A open standard 1250-1873 wanted
But I did test the same DUT by HP8753E and Advantest R3765BH or R3767C . They have the same results.R3765/7 are using Maury Cal. Kit. 從我的 iPhone 傳送 Dr. David Kirkby from Kirkby Microwave Ltd < drkirkby@...> 於 2018年10月30日 22:36 寫道：
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Please On Tue, 30 Oct 2018, 14:05 Yiu On Tony C via Groups.Io, <tonycheung_hk= [email protected]> wrote: Hi members :
Anyone still using HP85050A with 1250-1873? open standard ??
Any photos or extra can offer ??
You might want to consider asking on?
In my 8510A have the cal. standard file A1. when cal. with 85050B can see the actually reading have some error in value measurement value ?
I compare DUT measured with my 8753E VNA .
Any advise ?
The 8753 uses the 85031 (from memory) which is a fairly simple standard with a waveguide beyond cutoff. A fringing capacitance around 82 fF is defined, but that is not very accurate as the fringing capacitance depends on the protrusion of the centre contact which is not well defined. Measure a few APC7 connectors with connector guages from the 85050B. I am unsure if the 85050A has guages.?
The 85050B open pushes the centre contact to a defined position, so is more reproducible. The fringing capacitance is increased to around 100 fF.?
Obviously you need to have the cal kit set up properly.?
I do not have an open to sell.?
Regard
Tony Cheung
OCT 30 2018
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Re: HP85050A open standard 1250-1873 wanted
Dr. David Kirkby from Kirkby Microwave Ltd
Please On Tue, 30 Oct 2018, 14:05 Yiu On Tony C via Groups.Io, <tonycheung_hk= [email protected]> wrote: Hi members :
Anyone still using HP85050A with 1250-1873? open standard ??
Any photos or extra can offer ??
You might want to consider asking on?
In my 8510A have the cal. standard file A1. when cal. with 85050B can see the actually reading have some error in value measurement value ?
I compare DUT measured with my 8753E VNA .
Any advise ?
The 8753 uses the 85031 (from memory) which is a fairly simple standard with a waveguide beyond cutoff. A fringing capacitance around 82 fF is defined, but that is not very accurate as the fringing capacitance depends on the protrusion of the centre contact which is not well defined. Measure a few APC7 connectors with connector guages from the 85050B. I am unsure if the 85050A has guages.?
The 85050B open pushes the centre contact to a defined position, so is more reproducible. The fringing capacitance is increased to around 100 fF.?
Obviously you need to have the cal kit set up properly.?
I do not have an open to sell.?
Regard
Tony Cheung
OCT 30 2018
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Re: HP8405A - Uncommon component failure?
Ive seen those components fail before but usually with those failure tends to be mechanical rather than electrical.
Thermal cycling, mounting stress, defect in bonding leads etc. as they usually fail ‘open’ instead of short.
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
As to usenet i remember bang paths and telebit trailblazer modems
I.e. csiro!bigsite!foovax!barbox!me
As for google they get all my e-commerce mail as they do a reasonable job of keeping it spam free and making sure their MTA’s dont get blocked by spamhaus and other blacklist providers.
The tradeoff is some degree of privacy but since ecommerce vendors will sell your marketing data anyway not much of a loss.
And i have a separate private email system for the rest of my mail.
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HP85050A open standard 1250-1873 wanted
Hi members :
Anyone still using HP85050A with 1250-1873? open standard ??
Any photos or extra can offer ??
In my 8510A have the cal. standard file A1. when cal. with 85050B can see the actually reading have some error in value measurement value ?
I compare DUT measured with my 8753E VNA .
Any advise ?
Regard
Tony Cheung
OCT 30 2018
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
Dr. David Kirkby from Kirkby Microwave Ltd
Please note, at the bottom of each email is a link to "mute" a topic. For this thread, for example it is
for me. It might be a different link for others.?
Dave
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
All open source email clients support threading, including pine, many IMAP providers support it server-side, etc. Email has not been “designed” for many things because nobody had an idea what it may be useful for. Usenet’s downfall is that it’s a technology that doesn’t add much on top of email as currently implemented. And of course the mbox format is awesome, but that doesn’t preclude indices – a raw mbox file is a data-exchange medium, not access medium: I like being able to search my mail at a cost better than O(N*M), where M is some measure of the cost of a comparison – in most cases, you want it to be something more human-proof than a case-insensitive string or regex search. Mailbox indexing used to be poorly implemented, but that’s not the case anymore. Even the iOS’s built-in mail client handles it correctly, and does indexing in the background when plugged in, or incrementally, on a phone with 2G of RAM and a CPU that was hot tamales a decade ago, and is quite thermally constrained on top of that.
I don’t particularly wish that Usenet became a thing again: it seems gratuitous, and was a “good deal” at times when servers were huge and clients were tiny (a Z80-based Usenet reader would be just fine). These days, servers are often smaller than the clients, as datacenter costs aren’t trivial and renting a server with the capacity of even my current phone would be more than beer money. Even big providers like google scale and distribute their services so that the individual instances can be small. But, given an always-on, say, M68k system, even it should be able to index huge mailboxes in a modern fashion and offer very fast lookups, threading, etc. Something like a raspberry pi has no trouble with any of it. A$35 system… So, I’d say that email as implemented and used today isn’t as big of a bear as we make it out to be, when talking non-emotional terms.
Cheers, Kuba
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30 okt. 2018 kl. 00:38 skrev Sergey Kubushyn <ksi@...>:
On Tue, 30 Oct 2018, Bryan Fields wrote:
On 10/30/18 12:12 AM, Michael A. Terrell wrote:
Why should I have to change my Email service, just to please others? Your MUA is broken per RFC 2822 "Internet Message Format":
3.6.4. Identification fields
Though optional, every message SHOULD have a "Message-ID:" field.
Furthermore, reply messages SHOULD have "In-Reply-To:" and
"References:" fields as appropriate, as described below. SHOULD != MUST. Both are used within RFCs and they have DIFFERENT meaning.
But that is secondary to the fact that email was never supposed to be a
discussion instrument so nobody cares threading mail messages. Especially
those stored in random order in MBOX format on local machine that is usually
the case for any sane person -- never ever store ANYTHING on third party
server and remember that Microsoft is not an answer, it is a question and
the answer is "NO!".
What should and IS threaded by any sane _NEWS_reader are NEWS messages e.g.
from usenet. But those are _NOT_ emails and not addressed to anybody so they
form discussion threads. This is what they had been designed for.
Threaded email discussions are oxymoron. Email is NOT designed for
discussion threads. Emails are ADDRESSED messages from particular
address[es] to another particular address[es] and their threading is a poor
man's hack for proper newsgroups.
Ever tried usenet?
---
*
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
*
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
Old internet saying:
If a company provides a service to you for free, then you
are their product.
Gmail is free because Google (Alphabet actually) reads all of your
emails for interesting information, and uses that information
to create a profile of who they think you are, and what they think
your sick little self might like. They then sell that profile to any
company that is willing to pay for a list of people with the same
perversions as you...
So, try a little experiment. If you are male, engage in a gmail
conversation with a friend about feminine hygiene products, plastic
surgery vacations in Thailand, and baby stuff, and see what ads
start to show up when you surf the web without adblocker.
You will suddenly find an endless supply of ads for these things
everywhere you go.
Similarly, if you have google assistant enabled for voice on your
cell phone, it is listening to you all the time, and is sending the
audio back to Alphabet for interpretation and logging into your
profile. You can even log onto your google account and download
their favorite overheard conversation tidbits and keywords from your
phone...
[Note, if you have android, and use your voice to make your phone
do anything, you have google assistant enabled, and it is listening
to you.]
But sure, by all means give gmail all of your email correspondence.
-Chuck Harris
Orin Eman wrote:
...
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FWIW, I have an account at drizzle.com. I have gmail import all my
incoming email at drizzle.com such that it shows up in my gmail inbox. I
see that there are instructions for gmail to suck down email from Earthlink
too... I usually access gmail through a web browser, but use the app on
the iphone occasionally. Obviously, there is an Android app. The email
stays in googles cloud. I'm not concerned about the security, email isn't
a secure medium anyway.
As for threading, gmail does it just fine as long as the headers are
there. It's relatively rare that threads get broken up. They also have
semi-reasonable filtering, so I can sort lists into their own folders
(though they call it labelling, the effect is the same though you can put
more than one label on a given email).
There's nothing stopping one getting a gmail account, never giving out the
address and using it to import from other accounts. They give me the
option of sending from my drizzle account as necessary. In fact, should I
need to access my drizzle account directly, I'm going to have to call them
as I've forgotten the password.
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
Kuba,
Threading is nice, and most every email reader has it, but the nice
easy read you get with threading (assuming you never delete any emails
from your inbox) is just a list of message subject headers:
Subject: My message
...Subject RE: My message
.....Subject RE: My message
.......Subject RE: RE: My message.
.........Subject RE: RE: My message
...Subject RE: My message
... on and on till it scrolls off the right edge of the screen.
Then after seeing the above enlightening list of headers you see:
Subject: My message
Me too!
How does that help?
If I want to know what "Me too!" relates to, I have to go back to a
previous message in the thread, open it, and read it.
That's the theory...
But I can't because I have deleted the previous messages in order to
keep my Inbox manageable. That means they end up in my Trash folder,
unavailable to the thread handler in my email program. I don't even
see the threading for messages I have already read and deleted.
Periodically, I sift through my trash with a couple of scripts and put
the messages into an archive for each group, but the archive is
compressed, packed away in another folder, and unavailable to the
threading of the incoming messages in the inbox.
Frankly I have never found a "Me too!" to be compelling enough to
bother going back and searching for the message it applies to.
I just delete them unread. I delete all messages that have no quoted
text. If I reply to them at all, it is to complain about such messages
and to try to educate the sender about polite behavior on the group.
If you want your messages to be read, quote some of the previous
message.
-Chuck Harris
Kuba Ober wrote:
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I had threading and filtering into folders in ancient Eudora and pine over a decade ago… I don’t understand how one can manage without it, and how obsolete of an email client it would take not to have that functionality (perhaps off by default, but still easily enable-able). Every modern email reader, whether stand-alone or web-based, threads and filters messages into folders. I really wonder what sort of an antique client it takes not to have that functionality. I don’t see the need to delete any messages either, it seems like useless busywork and a waste of time, since we won’t ever run out of space. The time spent deleting the messages or manually organizing them is more expensive than the storage thus “saved”. They compress well, too.
Cheers, Kuba
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
DELETE
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On 10/30/2018 5:42 AM, David C. Partridge wrote: Enough already - this horse is already dead. <deliberately NOT quoting the endless discussion>
David
--
Dave
Manuals@...
www.ArtekManuals.com
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
Enough already - this horse is already dead. <deliberately NOT quoting the endless discussion>
David
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HP8405A - Uncommon component failure?
I guess we all have a mental hit-list of the components we all expect to find failed in the equipment we fix? - Tant caps & Carbon comp resistors anyone?
However when I decided to finally get round to fixing my 8405A in the space of a couple of hours found two that would not have put top of the list by a long way - an open-circuit 1k1 metal film resistor (on A16) and a 4n7 resin dipped silver mica cap (on A8) that had 'self-identified' as a 2k6 resistor. Both were running miles within their ratings in terms of voltage and power.
I don't think I've ever seen either of those types fail before so have I just been lucky up to now?
Adrian
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
On Oct 30, 2018, at 09:21, Tom Gardner <tggzzz@...> wrote:
SHOULD != MUST. Both are used within RFCs and they have DIFFERENT meaning. True.
“SHOULD” (upper case) is actually defined in RFC 2119, which says: 3. SHOULD This word [… means] that there may exist valid reasons in particular circumstances to ignore a particular item, but the full implications must be understood and carefully weighed before choosing a different course. So you have to have a good reason to violate a SHOULD. I bet that particular MUA doesn’t have a good reason (laziness of implementers is *not* a “valid reason”). But that is secondary to the fact that email was never supposed to be a
discussion instrument so nobody cares threading mail messages. […] False.
Indeed, it doesn’t get much falser than that. Discussion lists have been around for more than a third of a century. There is a proper way to participate in a discussion mailing list, and it probably is even written up somewhere — unfortunately, I don’t have time to pull that reference up right now, but maybe somebody else could. (This message is mainly intended as an example of how to reply to a message on a discussion list.) Grü?e, Carsten
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
On 30/10/18 04:38, Sergey Kubushyn wrote: On Tue, 30 Oct 2018, Bryan Fields wrote:
On 10/30/18 12:12 AM, Michael A. Terrell wrote:
Why should I have to change my Email service, just? to please others? Your MUA is broken per RFC 2822 "Internet Message Format":
3.6.4. Identification fields
? Though optional, every message SHOULD have a "Message-ID:" field.
? Furthermore, reply messages SHOULD have "In-Reply-To:" and
? "References:" fields as appropriate, as described below. SHOULD != MUST. Both are used within RFCs and they have DIFFERENT meaning. True. But that is secondary to the fact that email was never supposed to be a
discussion instrument so nobody cares threading mail messages. Especially
those stored in random order in MBOX format on local machine that is usually
the case for any sane person -- never ever store ANYTHING on third party
server and remember that Microsoft is not an answer, it is a question and
the answer is "NO!". False. I and other people and do care about it. ALL MUAs I've used since the 1980s (on Unix, Linux and Windows) have had that capability. You may not care, but you aren't the whole world. In particular you don't get to dictate how other people use the net. Sorry about that. Sorry to appear belligerent, but that's how you come across. What should and IS threaded by any sane _NEWS_reader are NEWS messages e.g.
from usenet. But those are _NOT_ emails and not addressed to anybody so they
form discussion threads. This is what they had been designed for.
Threaded email discussions are oxymoron. Email is NOT designed for
discussion threads. Emails are ADDRESSED messages from particular
address[es] to another particular address[es] and their threading is a poor man's hack for proper newsgroups. Emails are designed to communicate information. There are many ways of communicating information. Ever tried usenet? Yes, since the mid 80s.
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
On Mon, Oct 29, 2018 at 10:00 PM Michael A. Terrell < mike.terrell@...> wrote:
? ?How do I change the way an Android app lets me read my email? There is only one for Earthlink's web mail. I only download what I haven't deleted, when the 300 MB inbox is close to full. Other times I have to use another computer to access it, like while in a hurricane shelter. Those computers wiped out anything you download, when you log out. Other times, I use the Android app on a KODI TV set top box, which doesn't let me download any messages.
I have an archive of downloaded email going back over 20 years, but I can't always read email on my dedicated Email computer. I also have saved Usenet messages going back 21 years.
FWIW, I have an account at .? I have gmail import all my incoming email at such that it shows up in my gmail inbox.? I see that there are instructions for gmail to suck down email from Earthlink too...? I usually access gmail through a web browser, but use the app on the iphone occasionally.? Obviously, there is an Android app.? The email stays in googles cloud.? I'm not concerned about the security, email isn't a secure medium anyway.
As for threading, gmail does it just fine as long as the headers are there.? It's relatively rare that threads get broken up.? They also have semi-reasonable filtering, so I can sort lists into their own folders (though they call it labelling, the effect is the same though you can put more than one label on a given email).
There's nothing stopping one getting a gmail account, never giving out the address and using it to import from other accounts.? They give me the option of sending from my drizzle account as necessary.? In fact, should I need to access my drizzle account directly, I'm going to have to call them as I've forgotten the password.
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Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
Michael A. Terrell
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-----Original Message----- From: Dave McGuire <mcguire@...>
Sent: Oct 30, 2018 12:44 AM
To: [email protected]
Subject: Re: Quoting Prior Messages (Re: [HP-Agilent-Keysight-equipment] Transistors for the A17 voltage regulator 8642B)
On 10/30/2018 12:25 AM, Michael A. Terrell wrote:
There is nothing I an do about that, other than change providers and try to update my information on over 100 business websites. Frankly, I think that 99% of the internet is broken due to the low grade programmers who keep screwing with the software to add unwanted 'features', and who gut what you really need. Changing your mail program (MUAs, Mail User Agent) has NOTHING AT ALL
to do with changing mail *providers* or your email address! How do I change the way an Android app lets me read my email? There is only one for Earthlink's web mail. I only download what I haven't deleted, when the 300 MB inbox is close to full. Other times I have to use another computer to access it, like while in a hurricane shelter. Those computers wiped out anything you download, when you log out. Other times, I use the Android app on a KODI TV set top box, which doesn't let me download any messages. I have an archive of downloaded email going back over 20 years, but I can't always read email on my dedicated Email computer. I also have saved Usenet messages going back 21 years.
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Michael A. Terrell
Yiu On Tony C
David C. Partridge