serial number prefixes for the two???
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On 10/10/2018 2:26 PM, Peter Gottlieb wrote: A while ago I bought a 8970B noise figure meter but never got it running due to a bad YTO. Recently, thinking it would be interesting to play with, I bought another for parts, figuring I would make one good one.
To my surprise, internally they are quite different! The YTO in the second one is completely different, with an entirely different frequency range. Hmmm, that¡¯s interesting...
It turns out that the second unit has option 20, meaning it can go to 2 GHz. I am amazed how different these units are internally!
In any case the initial problem in the second unit appears to be in the controller which usually doesn¡¯t run at all. Or maybe power supply, I haven¡¯t dug into it. The unit was dropped hard at one point in its life as the back panel where the transformer is mounted is bent so I¡¯m going to look for a mechanical cause for the problems and instead of looking to fix the first unit concentrate on the option 20 one. Hopefully the YTO wasn¡¯t damaged in the drop.
It is just interesting to me that the slight increase in the top end frequency required such massive RF system changes.
Peter
--
Dave
Manuals@...
www.ArtekManuals.com
|
A while ago I bought a 8970B noise figure meter but never got it running due to a bad YTO. Recently, thinking it would be interesting to play with, I bought another for parts, figuring I would make one good one.
To my surprise, internally they are quite different! The YTO in the second one is completely different, with an entirely different frequency range. Hmmm, that¡¯s interesting...
It turns out that the second unit has option 20, meaning it can go to 2 GHz. I am amazed how different these units are internally!
In any case the initial problem in the second unit appears to be in the controller which usually doesn¡¯t run at all. Or maybe power supply, I haven¡¯t dug into it. The unit was dropped hard at one point in its life as the back panel where the transformer is mounted is bent so I¡¯m going to look for a mechanical cause for the problems and instead of looking to fix the first unit concentrate on the option 20 one. Hopefully the YTO wasn¡¯t damaged in the drop.
It is just interesting to me that the slight increase in the top end frequency required such massive RF system changes.
Peter
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Bill
The jan 74 manual should cover the 1339A unit ( though I don't have a copy of it.) I have Mil Manual TM 9-4935-601-14-7&P
Which does have the details on the A4 board 08640-60032. as well as your serial number in general
For the 1943A unit you will need manual 08640-90187
Your 1991 Manual is of only limited use on your units which are 1973 and 1979 units
I have both manuals available on my web site for order but do some looking around first as I think there may be free downloads yet available
Dave
www.ArtekManuals.com
manuals@...
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On 10/9/2018 8:17 PM, Willie wrote: I checked the 8640B that is not zeroing for S/N.? Here is what I found:
1339A01128
The A2 board is 08640 60032
The working unit is 1943A12442 but that could be off as I was reading it backwards through a mirror!
The two manuals? have are Jan 74 and May 91.? The Jan 74 manual is not complete
Hope that helps someone track down what might be wrong..
Thanks,
Bill A
Artekmedia wrote:
Bill
The 8640B was in production for nearly 20 years in the 70's and 80's and went through many changes over the years. For starters what are the serial numbers for your two units. Knowing that you have a better chance of getting the right manual. Knowing the actual part number of any given board in question is also helpful ( 08640-60xxx) as many units in circulation? are recipients of "organ donor" boards from earlier and later units and the top level serial number is not always indicative of what is actually inside these days . Armed with the above information we can recommend the manual you should be looking for to best cover your unit
Dave
manuals@...
On 10/9/2018 1:34 PM, Willie wrote:
I just acquired a second 8640B and it works well except for one minor issue.? The level meter does not zero at minimum level setting (CCW).? The meter is different from my previous one in that it is auto ranging.? I thought that was the cause but when I toggle the output off, the meter stays a little over 1 on the 10 scale.? FM and AM zero OK.
In going through the manual, I found the drive offset pot (20K) on the A2 board.? My manual and that board do not agree.? My manual shows two IC's and 5 transistors.? The board has 4 IC's and two transistors.? Also I could not find TP4 as shown on the schematic SS13.? I tried adjusting the pot for a zero on the meter but ran out of adjustment.? Anyone have experience with this?
My HP435A agrees with full scale on the 8640B.? 5V and -20V and +20V are there.? I have not gone through all the manual changes. Maybe there is something there.
Thanks for any help.
Bill A
--
Dave
Manuals@...
www.ArtekManuals.com
|
I checked the 8640B that is not zeroing for S/N. Here is what I found:
1339A01128
The A2 board is 08640 60032
The working unit is 1943A12442 but that could be off as I was reading it backwards through a mirror!
The two manuals have are Jan 74 and May 91. The Jan 74 manual is not complete
Hope that helps someone track down what might be wrong..
Thanks,
Bill A
Artekmedia wrote:
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Bill
The 8640B was in production for nearly 20 years in the 70's and 80's and went through many changes over the years. For starters what are the serial numbers for your two units. Knowing that you have a better chance of getting the right manual. Knowing the actual part number of any given board in question is also helpful ( 08640-60xxx) as many units in circulation are recipients of "organ donor" boards from earlier and later units and the top level serial number is not always indicative of what is actually inside these days . Armed with the above information we can recommend the manual you should be looking for to best cover your unit
Dave
manuals@...
On 10/9/2018 1:34 PM, Willie wrote:
I just acquired a second 8640B and it works well except for one minor issue. The level meter does not zero at minimum level setting (CCW). The meter is different from my previous one in that it is auto ranging. I thought that was the cause but when I toggle the output off, the meter stays a little over 1 on the 10 scale. FM and AM zero OK.
In going through the manual, I found the drive offset pot (20K) on the A2 board. My manual and that board do not agree. My manual shows two IC's and 5 transistors. The board has 4 IC's and two transistors. Also I could not find TP4 as shown on the schematic SS13. I tried adjusting the pot for a zero on the meter but ran out of adjustment. Anyone have experience with this?
My HP435A agrees with full scale on the 8640B. 5V and -20V and +20V are there. I have not gone through all the manual changes. Maybe there is something there.
Thanks for any help.
Bill A
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Re: MATLAB GPIB Instrument Control Applications
Thank you very much !!?
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On Mon, Oct 1, 2018 at 05:13 PM, Dick Benson wrote:
https://www.mathworks.com/matlabcentral/fileexchange/68910-vna-impedance-measurement
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Bill
The 8640B was in production for nearly 20 years in the 70's and 80's and went through many changes over the years. For starters what are the serial numbers for your two units. Knowing that you have a better chance of getting the right manual. Knowing the actual part number of any given board in question is also helpful ( 08640-60xxx) as many units in circulation? are recipients of "organ donor" boards from earlier and later units and the top level serial number is not always indicative of what is actually inside these days . Armed with the above information we can recommend the manual you should be looking for to best cover your unit
Dave
manuals@...
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Show quoted text
On 10/9/2018 1:34 PM, Willie wrote: I just acquired a second 8640B and it works well except for one minor issue.? The level meter does not zero at minimum level setting (CCW).? The meter is different from my previous one in that it is auto ranging.? I thought that was the cause but when I toggle the output off, the meter stays a little over 1 on the 10 scale.? FM and AM zero OK.
In going through the manual, I found the drive offset pot (20K) on the A2 board.? My manual and that board do not agree.? My manual shows two IC's and 5 transistors.? The board has 4 IC's and two transistors.? Also I could not find TP4 as shown on the schematic SS13.? I tried adjusting the pot for a zero on the meter but ran out of adjustment.? Anyone have experience with this?
My HP435A agrees with full scale on the 8640B.? 5V and -20V and +20V are there.? I have not gone through all the manual changes. Maybe there is something there.
Thanks for any help.
Bill A
--
Dave
Manuals@...
www.ArtekManuals.com
|
I just acquired a second 8640B and it works well except for one minor issue. The level meter does not zero at minimum level setting (CCW). The meter is different from my previous one in that it is auto ranging. I thought that was the cause but when I toggle the output off, the meter stays a little over 1 on the 10 scale. FM and AM zero OK.
In going through the manual, I found the drive offset pot (20K) on the A2 board. My manual and that board do not agree. My manual shows two IC's and 5 transistors. The board has 4 IC's and two transistors. Also I could not find TP4 as shown on the schematic SS13. I tried adjusting the pot for a zero on the meter but ran out of adjustment. Anyone have experience with this?
My HP435A agrees with full scale on the 8640B. 5V and -20V and +20V are there. I have not gone through all the manual changes. Maybe there is something there.
Thanks for any help.
Bill A
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Re: HP Manuals & Catalogs
Hi!
How much for postage to USA for 5350A & 83592A manuals?? My German is not so good.
73
Jeff
WA3ZKR
In a message dated 10/9/2018 5:35:27 AM Eastern Standard Time, df6na@... writes:
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Re: Some suspiciously cheap RF test kit on eBay UK
At 10:11 AM 10/9/2018, Scott McGrath wrote: The problem with using an alternative DNS provider is some slimy ISP's disallow use of alternative DNS under the guise of "protecting" you. There are also wifi networks that disallow use of alternate DNS providers - my local library is an example. Of course, I do very little there - I access some online resources that can only be accessed when I am on the library network, and the only other thing I do there is check my email. My laptop has a utility to automatically configure wifi connections, so when I connect at the library it automatically uses the library network for DNS resolution. Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
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Re: Some suspiciously cheap RF test kit on eBay UK
The problem with using an alternative DNS provider is some slimy ISP¡¯s disallow use of alternative DNS under the guise of ¡®protecting¡¯ you.
In reality it¡¯s all about monetizing your internet activity and redirecting you to ¡®preferred¡¯ partners. Use of alternative providers makes that much harder for an ISP to do those things. Not impossible mind you just much more expensive.
Whoever controls the DNS controls what you see on the internet and what you don¡¯t.
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Re: Some suspiciously cheap RF test kit on eBay UK
On 09/10/18 09:38, Dr. David Kirkby
from Kirkby Microwave Ltd wrote:
On Tue, 9 Oct 2018 at 07:53, Tom Gardner < tggzzz@...>
wrote:
A wouldn't have thought the
"ownership" carries any useful information. I presume it
can be easily forged. As a colleague of mine, Stefek
Zaba, used to tell everybody in the mid-late 90s, "my
name is Donald Duck, and I have a digital certificate to
prove it".
The only important part of a digital certificate is that
it is vouched for by the chain of certificates to a
trusted root certificate. If you trust the chain then
you have (some) trust in the site.
Of course it isn't necessary to have a certificate that
has a chain to a trusted root certificate. One system I
worked on had a "self-signed" certificate, and that was
completely sufficient for our purposes.
I too have created self-signed
certificates, but they would be flagged by any modern
browser as being self-signed, so should be a warning to
someone that something is amiss.
Agreed.
Just as a causual user of eBay, I'm
finding hacked accounts all the time by accident. There
seems to be something wrong with their security system that
is permitting these accounts to be hyjacked.
It could well be outside ebay's ability to control. Classic example
would be a password used in multiple places, and one of the other
places losing the info.
I don't know how many people get
tricked by the eBay scammers and pay by bank transfer.
Sufficient, I presume :(
Even solicitors have been duped with their client's money for a
house purchase: all it takes is a simple "our bank account has
changed" email, and some dozy admins.
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Re: Some suspiciously cheap RF test kit on eBay UK
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 9 Oct 2018 at 07:53, Tom Gardner < tggzzz@...> wrote:
A wouldn't have thought the "ownership" carries any useful
information. I presume it can be easily forged. As a colleague of
mine, Stefek Zaba, used to tell everybody in the mid-late 90s, "my
name is Donald Duck, and I have a digital certificate to prove it".
The only important part of a digital certificate is that it is
vouched for by the chain of certificates to a trusted root
certificate. If you trust the chain then you have (some) trust in
the site.
Of course it isn't necessary to have a certificate that has a chain
to a trusted root certificate. One system I worked on had a
"self-signed" certificate, and that was completely sufficient for
our purposes.
I too have created self-signed certificates, but they would be flagged by any modern browser as being self-signed, so should be a warning to someone that something is amiss.
Just as a causual user of eBay, I'm finding hacked accounts all the time by accident. There seems to be something wrong with their security system that is permitting these accounts to be hyjacked. I don't know how many people get tricked by the eBay scammers and pay by bank transfer.
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: Some suspiciously cheap RF test kit on eBay UK
In this instance, the "clue" (other than the dodgey deal itself) was
that the "Daily Deals" fake ebay site was not TLS secured.? It was
plain old http:
If you try to go to ebay (.com or .co.uk for example) using http,
you will automatically get redirected to the https secured pages.
Doing a traceroute on the daily deals link address, and then trying
to reverse DNS the resulting endpoint IP address, also flagged up
suspicions.
Any site that isn't using TLS these days, that purports to be ebay
is instantly suspicious.??? (Another good reason not to hide details
in the URL bar.? Google, are you listening?? Of course they are, but
only 'bots.)
As to DNS settings, not sure which Dave the comment was targeted at,
but I already use Quad9 and their secondary address (that, without
poking at the settings I can't remember) in both my home router and
travelling PC.?? Sure, it stops a lot, but stuff like that due to
being hosted on Digital Ocean's systems (a valid hosting company)
still get through.
Take care.
73.
Dave G0WBX
(Too many "Dave's" on here...)
Re: Some suspiciously cheap RF test kit
on eBay UK
From: Dave
McGuire
Date: Mon, 08 Oct 2018 09:54:08 PDT
...which is an excellent argument in support of "encryption
everywhere". The scumbags will find a way around that (like simply
registering and installing SSL certificates) but the trick is to
stay
one step ahead of them.
The point, though, is that there's no way to tell what domains are
"fake". After all, what constitutes "fake" in this context? The
fraudulent listing is a fully legitimate domain name, there is
nothing
"fake" about it other than the fact that, as a substring, it
includes
the same sequence of characters as that of a well-known web site.
That is actually an extraordinarily difficult problem to solve
without
creating lots of false positives.
-Dave
--
Created on and sent from a Unix like PC running and using free and open source software.
::
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Re: Some suspiciously cheap RF test kit on eBay UK
On 08/10/18 23:00, Dr. David Kirkby
from Kirkby Microwave Ltd wrote:
Looking at the SSL certificates of , and
shows something odd.
For ?
"Owner: This website does not supply ownership
information."
For
"Owner: This website does not supply ownership
information."
For
"Owner: Kirkby Microwave Ltd"
(see attached screen
shots)
So why the %?$ don't eBay
at least have their SSL certificates with their
ownership in? I think the EV SSL certificate
cost me $80 for a year, so hardly a fortune.
A wouldn't have thought the "ownership" carries any useful
information. I presume it can be easily forged. As a colleague of
mine, Stefek Zaba, used to tell everybody in the mid-late 90s, "my
name is Donald Duck, and I have a digital certificate to prove it".
The only important part of a digital certificate is that it is
vouched for by the chain of certificates to a trusted root
certificate. If you trust the chain then you have (some) trust in
the site.
Of course it isn't necessary to have a certificate that has a chain
to a trusted root certificate. One system I worked on had a
"self-signed" certificate, and that was completely sufficient for
our purposes.
"If you think encryption will solve your problem, you don't
understand encryption and you don't understand your problem".
Then s/encryption/identity/ (as the UK government has spent a lot of
money finding out with its plans for digital identity certificates
for all the Queens's subjects)
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Re: Some suspiciously cheap RF test kit on eBay UK
My apologies. I was not completely up to speed with public DNS providers and just assumed the worst. :^)
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On 9/10/18 12:49 PM, bownes wrote: 9.9.9.9 isn¡¯t Google. It¡¯s a friend, former co-worker, and person of great trust.
8.8.8.8 is google.
On Oct 8, 2018, at 18:11, Andy ZL3AG via Groups.Io <zl3ag@...> wrote:
On 9/10/18 5:50 AM, bownes wrote:
Well said Dave.
But you and I are attentive to domain names due to our rather DNS centric backgrounds. Other folks might want to think about using 9.9.9.9 as their DNS server (as opposed to the one your ISP hands you) as it has a number of features to knock down the spam and scams.
Bob
I trust my ISP more than I trust Google.
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Re: Some suspiciously cheap RF test kit on eBay UK
9.9.9.9 isn¡¯t Google. It¡¯s a friend, former co-worker, and person of great trust.
8.8.8.8 is google.
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On Oct 8, 2018, at 18:11, Andy ZL3AG via Groups.Io <zl3ag@...> wrote:
On 9/10/18 5:50 AM, bownes wrote:
Well said Dave.
But you and I are attentive to domain names due to our rather DNS centric backgrounds. Other folks might want to think about using 9.9.9.9 as their DNS server (as opposed to the one your ISP hands you) as it has a number of features to knock down the spam and scams.
Bob
I trust my ISP more than I trust Google.
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Re: Some suspiciously cheap RF test kit on eBay UK
On 9/10/18 5:50 AM, bownes wrote: Well said Dave.
But you and I are attentive to domain names due to our rather DNS centric backgrounds. Other folks might want to think about using 9.9.9.9 as their DNS server (as opposed to the one your ISP hands you) as it has a number of features to knock down the spam and scams.
Bob
I trust my ISP more than I trust Google.
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Re: Some suspiciously cheap RF test kit on eBay UK
Dr. David Kirkby from Kirkby Microwave Ltd
On Mon, 8 Oct 2018 at 17:54, Dave McGuire < mcguire@...> wrote:
? ...which is an excellent argument in support of "encryption
everywhere".? The scumbags will find a way around that (like simply
registering and installing SSL certificates) but the trick is to stay
one step ahead of them.
? The point, though, is that there's no way to tell what domains are
"fake".? After all, what constitutes "fake" in this context?? The
fraudulent listing is a fully legitimate domain name, there is nothing
"fake" about it other than the fact that, as a substring, it includes
the same sequence of characters as that of a well-known web site.
? That is actually an extraordinarily difficult problem to solve without
creating lots of false positives.
? ? ? ? ? ? ?-Dave
Do you think EV SSL certificates, along with public education, could play any role? So when someone clicks on a greed padlock in their browser bar, then can determine the owner of a domain?
Looking at the SSL certificates of , and shows something odd.
For ? "Owner: This website does not supply ownership information."
For "Owner: This website does not supply ownership information."
For "Owner: Kirkby Microwave Ltd"
(see attached screen shots)
So why the %?$ don't eBay at least have their SSL certificates with their ownership in? I think the EV SSL certificate cost me $80 for a year, so hardly a fortune.
Neither Keysight nor Anritsu have EV SSL certicates, although Rohde and Schwarz do. But eBay is a prime target for these sort of attacks, so I'm amazed that like almost any bank, PayPal etc, eBay don't get EV SSL certificates - and eductate people on what to look for.?
Anyway, I won my auction for the 3 GHz impedance analyzer for ?310 - see picture attached. I will see how long it takes eBay to tell me not to pay for it. Of course I have not paid, as I knew it was a scam, but it does not stop me bidding on scams.
-- 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: Some suspiciously cheap RF test kit on eBay UK
Aside from the ¡®_¡¯, both are technically valid. There are no special reserved words like ¡®www¡¯, ¡®mail¡¯, etc, but some have become popular conventions.
Bob
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On Oct 8, 2018, at 15:59, Adrian <Adrian@...> wrote:
Am I right that the format for the sub domain is that it must precede the main thus:
()whatever.sub.domain.main_domain.com/
I realise that won't help much with an all numbers domain but does help with most legitimate sites
so 'mail.your_bank.com/' is ok but 'your_bank.mail.com/' is not?
Adrian
On 10/8/2018 7:41 PM, PAUL NICKALLS via Groups.Io wrote:
Always look for the last full stop before the "/". It gives a very good clue as to what is going on.
Paul.
On 08/10/2018 17:09, pianovt via Groups.Io wrote:
Aside from the obvious weekend ebay scam, there is something very disturbing here. I am talking about how well they disguised their web site URL.
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Patricio A. Greco
bownes
