Re: Rad Lab was NOT in Tuxedo Park! MIT
Mixing two stories. Loomis tested first Maggie in Tuxedo Park.
Rad Lab was at MIT.
Please review your history!? I teach this stuff and it pains me to see it corrupted.
Jeff Kruth
Technical Historian
|
Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] Issue with homemade diode power sensor for HP meters
Regarding the TFT ?Marconi?
power meter ?they had 2? thermisters? at 100 ohm each
?And connected so that DC they added up
to 200 ohm but presented a 50? to an AC signal
?
The power sensor was easily tested as the
2 large pins on the convector should read 200 ohm
?
?
I have such an animal here a GM 460B with that TFT hermocouple. It is
an ancient beast. They got bought up by Marconi down the line.
https://patents.google.com/patent/US3384819
No virus found in this message.
Checked by AVG -
Version: 2016.0.8048 / Virus Database: 4793/15883 - Release Date: 08/14/18
Internal Virus Database is out of date.
|
Re: Warning to buy equipment on Ebay on auctions using GSP (global shipping programme)
This happens to me occasionally (I buy a lot of gear from the US). In one case they told me the item can't be exported (it was a standard RAID controller that is sold all across the world). Another time the item exceeded the allowed size and was 'destroyed' (i.e. sold off by Pittney Bowes) while I was refunded.
Overall, GSP is OK. From the side of an European buyer it means shipping costs are often very reasonable, and most of the time the item arrives on time. I also know what an item is going to cost me, including customs, which is an advantage.Occasionally however, Pittney Bowes (who operate GSP for ebay) screw up, and if one of their monkeys doesn't understand what a part is for they may select the wrong sitem category or believe it's something hyper-special secret gizmo no-one else than the US is allowed to own.
If they blocked that 8593E it appears the person who dealt with your package in Pittney Bowes was a moron. Unfortunately there's nothing you can do, but if you buy another 8593E then it very likely will just be sent to you as the first one should have been.
|
Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] Issue with homemade diode power sensor for HP meters
Thanks for the Rad Lab link. It appears that all the volumes are available in PDF format. I'm downloading them all now. Having read a history of the Rad Lab and a biography of the man responsible, Alfred Loomis, it should be a lot of fun to read.
For those not aware of it, the Rad Lab existed in Tuxedo Park, NY as a personal project of Alfred Loomis before WW II. Loomis was also involved in building the cyclotron at Berkeley. Lui Alvarez made an off hand comment to Loomis one evening that if they couldn't get copper they could use aluminum. Alvarez was blow away the next morning when Loomis told him it was not possible to build the magnets with aluminum wire for any of the designs being discussed. Loomis had stayed up all night making the calculations.
Loomis invented LORAN in the shower after a conversation with a Brit who was visiting. They wanted to name it after him, but he declined so they came up with a phrase to match the acronym.
Loomis closed the Rad Lab at the end of the war because he didn't think the government should be involved in research except in exigent circumstances such as war.
|
Re: Warning to buy equipment on Ebay on auctions using GSP (global shipping programme)
Battery fitted inside equipment is exempt ? David ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Robert G8RPI via Groups.Io
Sent: 22 November 2018 12:58
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] Warning to buy equipment on Ebay on auctions using GSP (global shipping programme) ? Ahh the GSP "police"
There are two main reasons why GSP may say something is restricted
1/ it's hazardous to ship e.g. batteries chemicals. The rules on batteries are complex, but a internally installed memory back-up lithium is NOT grounds to classify as hazardous.?The 8593E does have?a battery?marking on them which may have triggered?the stop?However the "safe" option for the GSP is not to ship if in doubt. Obviously shipping back to seller is impossible.
The second reason is "military" or other classified equipment i.e. items controlled by ITAR or EAR (google them)
There is no reason why these should not be returned to the seller.
Robert G8RPI.
|
Re: Warning to buy equipment on Ebay on auctions using GSP (global shipping programme)
Ahh the GSP "police" There are two main reasons why GSP may say something is restricted 1/ it's hazardous to ship e.g. batteries chemicals. The rules on batteries are complex, but a internally installed memory back-up lithium is NOT grounds to classify as hazardous.?The 8593E does have?a battery?marking on them which may have triggered?the stop?However the "safe" option for the GSP is not to ship if in doubt. Obviously shipping back to seller is impossible. The second reason is "military" or other classified equipment i.e. items controlled by ITAR or EAR (google them) There is no reason why these should not be returned to the seller. Robert G8RPI.
|
Re: Warning to buy equipment on Ebay on auctions using GSP (global shipping programme)
Dr. David Kirkby from Kirkby Microwave Ltd
On Thu, 22 Nov 2018 at 09:27, Peter Hansen < oz1lpr@...> wrote:
I just bought a HP 8593E on ebay. It was going through the Global Shipping Programme (GSP). For no good reason they said it is restricted unit and it cannot be exported to Denmark.
The seller will also not get it back. The message to was unit must be destroyed.
Both me and the seller was refunded but what is going on.
I heard many of?that type of equipement is restriced and will be destroyed if exported.
Does anyone else have had same?problems ?. ??
Or is it the Global shipping programme that has gotten something wrong ?
regards Peter??
Someone I know had a lithium ion battery distroyed. The seller should never have shipped such an item in the first place, and the seller lost his money.
It seems the GSP was kind to the seller in this case, but there are some items that can't be shipped. There are severe restions on Lithium ion batteries, especially if they need to go on a plane. Some thing are also covered by ITAR (International Traffic in Arms Regulations).?
The GSP has ****ed up with me, but both me and the seller got a refund. But that was because they sent a tiger figurine rather than a cal kit. Items do get mixed up. I would suggest sticking the name and address of the sender and recipricant on the actual item, which will reduce the chances of a screwup.
--
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
|
Warning to buy equipment on Ebay on auctions using GSP (global shipping programme)
I just bought a HP 8593E on ebay. It was going through the Global Shipping Programme (GSP). For no good reason they said it is restricted unit and it cannot be exported to Denmark.
The seller will also not get it back. The message to was unit must be destroyed.
Both me and the seller was refunded but what is going on.
I heard many of?that type of equipement is restriced and will be destroyed if exported.
Does anyone else have had same?problems ?. ??
Or is it the Global shipping programme that has gotten something wrong ?
regards Peter??
|
Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] Issue with homemade diode power sensor for HP meters
The GM / Marconi TfT deivces are thermocouple arrays. Bismuth /nichrome couples bad as a electrical generation device but can be made to match 50R. The resistor thermocouple types were common in RF ammeters and some power meters. The early?Marconi TF144 signal generator models used them for the output meter. The classic thermistor detector is the HP 478A that was first used?with the 431A power meter around 1961 and still made today at $5000 a pop. The analogue ?432B power meter was discontinued a few years ago with a final price of over $10,000 but the pair can be picked up for a few hundred dollars used. They built a new digital meter for the 478A the N432A at $10,000. but none if these appear in the Keysight power meter guide tables. So why is this "old tech" still made? the answer is in the guide: "Not discussed is the Keysight family of thermistor sensors and the associated Keysight 432A power meter. This venerable technology now is used almost exclusively for the standardization and traceability of power measurements from the U.S. National Institute of Standards and Technology and other international standards agencies. Because the Keysight 432A power meter and thermistor sensor technology is based on the highly precise DC-substitution method, the sensors are used as transfer standards, traveling between the user’s primary lab and the NIST measurement services laboratory. Users interested in such metrology power-transfer processes may request Keysight’s AN 64-1, 5965-6630E and AN 64-4, 5965-8167E application notes." Basically you can use a head with any 431/432/N432 meter and a accurate DC?DVM to get transfer accuracy to?a national standard. The "meter" is just a servo to balance the bridge and the accuracy is at the DC voltage. They do special variants of the head?with larger blocking capacitors for low frequency work. ? Robert G8RPI.
?
|
Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] Issue with homemade diode power sensor for HP meters
(It appears that my list of the RadLab books came from:
This link no longer works but:
Does and I did get volume 11 from there.
At MIT, I find a page about the series, but not the texts of the volumes:
)
In the second above, page 81 mention is made of “bolometers”, being
implemented with thermistors and bolometer, these having negative and
positive temperature coefficients. It goes on to describe bridge circuits and
the characteristics of the measurement elements. There's a copy of the Rad Lab series on ko4bb.com: -- john, KE5FX
|
Re: Tips on repairing the stick attenuator in the HP86603A
Part number would be 86603- 60074  Never had to fix on so can't help further Robert G8RPI.
|
Re: Tips on repairing the stick attenuator in the HP86603A
Perhaps a picture would be useful too.
Daun
Daun E. Yeagley II, N8ASB
On 11/21/2018 12:19 PM, Glenn Little
wrote:
toggle quoted message
Show quoted text
I guess a part number for the attenuator in question would help.
Everyone does not have 86603A manuals to check the part number.
The o-ring failures are quite common.
The attenuators with o-rings are used in a number of instruments.
Without the attenuator part number, who would know that your
attenuator is of a different design.
Glenn
On 11/21/2018 10:13 AM, Jeff Kruth
via Groups.Io wrote:
I had asked if anyone
was familiar with this type of atten. NOT the 8495
style, but a long stick. I guess no one reads. NO O
rings.
Jeff
In a message dated 11/20/2018 7:02:42 PM Eastern Standard
Time, glennmaillist@...
writes:
Here is a video on repairing one of these
attenuators:
The O-Rings are 2mm od x 1 mm id x 0.5mm thick.
Theses are used in watch making.
Hope this helps
Glenn
On 11/20/2018 6:31 PM, g lowrey wrote:
> Hey Jeff. Have you measured one to check the size? I
have several
> sources that might be able to supply them -
> 73,
> Bo L.
>
> On 11/20/18, Jeff Kruth via Groups.Io <kmec= [email protected]>
wrote:
>> Hi All!
>> Dont ask why, but I am resurrecting several HP
8660D generators with the
>> HP86603A plugin. The attenuators are "sticky", get
stuck in a certain
>> position. If you have experience with this exact
type of stick attenuator
>> (long silver block) with the 3 - 40 dB, 20 dB,
& 10 dB sections and can
>> advise how to make a reliable repair, I would love
to hear about it. Several
>> that I cleaned the solenoid shafts on seemed to be
working only to stick
>> again. I do not know how to search the archives as
well, can someone
>> advise?Thanks!73Jeff Kruth
>>
>>
>>
>>
>
>
>
--
-----------------------------------------------------------------------
Glenn Little? ? ? ? ? ? ? ? ARRL Technical Specialist? QCWA?
LM 28417
Amateur Callsign:? WB4UIV? ? ? ? ? ? wb4uiv@...? ?
AMSAT LM 2178
QTH:? Goose Creek, SC USA (EM92xx)? USSVI LM? NRA LM? SBE
ARRL TAPR
"It is not the class of license that the Amateur holds but
the class
of the Amateur that holds the license"
--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"
|
Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] Issue with homemade diode power sensor for HP meters
Ham Radio magazine (Dec. '77) had an article on building a "bolo-meter" type rf power meter ...Used small light bulbs in the sensor . I found a few pilot lights from old cb's that had the right resistance curve ... Also in April '86 an article using a "zero bias hot carrier diode"? chopper stabilized (with relays)
Jim
On Wednesday, November 21, 2018, 7:18:10 AM PST, Roy Morgan <k1lky68@...> wrote:
Chuck and others,
No doubt you are right about the small light bulb been used:? Here is my memory from EE school:
In ancient times, the 1960’s (if I remember right) a bolometer system was implemented with a common low current fuse.? It was arranged in a bridge circuit of sorts: It’s resistance was adjusted with DC current by a “zero setting” arrangement to get zero indication on a meter.? Then when RF power was applied, the bridge/feedback circuit automatically rebalanced the thing back to the resistance set earlier - the reduction in (dc?) power drove the indicator to show the RF power that was being applied.
One advantage of this scheme is that the unavoidable non-linearities in the bolometer fuse did not affect the measurement, since the bolometer was returned to its initial resistance/dissipation condition.? This basic scheme of “first set null balance, and then return the bridge to null when the unknown is introduced” was used throughout General Radio bridges of all sorts.? I would expect the GR instruments to include a bloomer-based power indicator, though I am not familiar with it/them.
One (or more) of the MIT Radiation Lab series of books covers this topic, and quite thoroughly.? I have a small group of those books “in storage” here and can look among them before the temperature goes too far below freezing.? But see below for an online example of Volume 11.
Likely one of these covers the topic:
8. Principles of microwave circuits - Montgomery, C. G.; Purcell, E. M. and Dicke, R. H. (1948)
11. Technique of microwave measurements - Montgomery, C. G. (1947)
(It appears that my list of the RadLab books came from:
This link no longer works but:
Does and I did get volume 11 from there.
At MIT, I find a page about the series, but not the texts of the volumes:
)
In the second above, page 81 mention is made of “bolometers”, being implemented with thermistors and bolometer, these having negative and positive temperature coefficients.? It goes on to describe bridge circuits and the characteristics of the measurement elements.
Roy
> On Nov 20, 2018, at 10:20 AM, Chuck Harris < cfharris@...> wrote: >
> A bolometer is not a thermocouple sensor.? What it is is a
> small lightbulb filament in a vacuum that is exposed to the
> RF power. ...
> If I recall correctly, Bolometers were used in a bridge circuit,
> where you applied AC power, and the bridge measured the resistance
> of the filament.? Next, you applied DC power, increasing the
> level until the resistance measured by the bridge matched that of
> the unknown RF power source.? At that point, the DC power was equal
> to the unknown RF power source's power.
>
> -Chuck Harris
Roy Morgan
K1LKY since 1958
|
Re: Readings from 436A power meter using 82357B USB-GPIB?
Hello,
Addressing another device using interactive IO doesn't seem to release the 436. What I did find out though was that viRead - wich is what interactive IO actually does - gets 14 characters back, but it expected 1024... I guess I IO doesn't get an end of line from the 436 and decides it never returned enough characters... Reading the 436 manual, it's clearly stated that it returns exactly 14 characters for each read. So, a response is given, but asking in the wrong way gives an error, not due to the instrument, but due to the setup of I IO...
I found a couple of nice functions in the VISA? library - there is a way to deassert the REN line for example. I know now that it isn't needed.
Nevertheless, this exercise was good for learning a bit more about Keysight (Agilent/HP) Connection Expert, Interactive IO and, most importantly, how to get the communication working the the VISA library!
Regards,
? Staffan
|
Re: Tips on repairing the stick attenuator in the HP86603A
I guess a part number for the attenuator in question would help.
Everyone does not have 86603A manuals to check the part number.
The o-ring failures are quite common.
The attenuators with o-rings are used in a number of instruments.
Without the attenuator part number, who would know that your
attenuator is of a different design.
Glenn
On 11/21/2018 10:13 AM, Jeff Kruth via
Groups.Io wrote:
I had asked if anyone was familiar with this
type of atten. NOT the 8495 style, but a long stick. I
guess no one reads. NO O rings.
Jeff
In a message dated 11/20/2018 7:02:42 PM Eastern Standard Time,
glennmaillist@... writes:
Here is a video on repairing one of these
attenuators:
The O-Rings are 2mm od x 1 mm id x 0.5mm thick.
Theses are used in watch making.
Hope this helps
Glenn
On 11/20/2018 6:31 PM, g lowrey wrote:
> Hey Jeff. Have you measured one to check the size? I have
several
> sources that might be able to supply them -
> 73,
> Bo L.
>
> On 11/20/18, Jeff Kruth via Groups.Io <kmec= [email protected]>
wrote:
>> Hi All!
>> Dont ask why, but I am resurrecting several HP 8660D
generators with the
>> HP86603A plugin. The attenuators are "sticky", get
stuck in a certain
>> position. If you have experience with this exact type
of stick attenuator
>> (long silver block) with the 3 - 40 dB, 20 dB, &
10 dB sections and can
>> advise how to make a reliable repair, I would love to
hear about it. Several
>> that I cleaned the solenoid shafts on seemed to be
working only to stick
>> again. I do not know how to search the archives as
well, can someone
>> advise?Thanks!73Jeff Kruth
>>
>>
>>
>>
>
>
>
--
-----------------------------------------------------------------------
Glenn Little? ? ? ? ? ? ? ? ARRL Technical Specialist? QCWA?
LM 28417
Amateur Callsign:? WB4UIV? ? ? ? ? ? wb4uiv@...? ?
AMSAT LM 2178
QTH:? Goose Creek, SC USA (EM92xx)? USSVI LM? NRA LM? SBE ARRL
TAPR
"It is not the class of license that the Amateur holds but the
class
of the Amateur that holds the license"
--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"
|
Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] Issue with homemade diode power sensor for HP meters
Chuck and others, No doubt you are right about the small light bulb been used: Here is my memory from EE school: In ancient times, the 1960’s (if I remember right) a bolometer system was implemented with a common low current fuse. It was arranged in a bridge circuit of sorts: It’s resistance was adjusted with DC current by a “zero setting” arrangement to get zero indication on a meter. Then when RF power was applied, the bridge/feedback circuit automatically rebalanced the thing back to the resistance set earlier - the reduction in (dc?) power drove the indicator to show the RF power that was being applied. One advantage of this scheme is that the unavoidable non-linearities in the bolometer fuse did not affect the measurement, since the bolometer was returned to its initial resistance/dissipation condition. This basic scheme of “first set null balance, and then return the bridge to null when the unknown is introduced” was used throughout General Radio bridges of all sorts. I would expect the GR instruments to include a bloomer-based power indicator, though I am not familiar with it/them. One (or more) of the MIT Radiation Lab series of books covers this topic, and quite thoroughly. I have a small group of those books “in storage” here and can look among them before the temperature goes too far below freezing. But see below for an online example of Volume 11. Likely one of these covers the topic: 8. Principles of microwave circuits - Montgomery, C. G.; Purcell, E. M. and Dicke, R. H. (1948) 11. Technique of microwave measurements - Montgomery, C. G. (1947) (It appears that my list of the RadLab books came from: This link no longer works but: Does and I did get volume 11 from there. At MIT, I find a page about the series, but not the texts of the volumes: ) In the second above, page 81 mention is made of “bolometers”, being implemented with thermistors and bolometer, these having negative and positive temperature coefficients. It goes on to describe bridge circuits and the characteristics of the measurement elements. Roy On Nov 20, 2018, at 10:20 AM, Chuck Harris <cfharris@...> wrote:
A bolometer is not a thermocouple sensor. What it is is a
small lightbulb filament in a vacuum that is exposed to the
RF power. ...
If I recall correctly, Bolometers were used in a bridge circuit,
where you applied AC power, and the bridge measured the resistance
of the filament. Next, you applied DC power, increasing the
level until the resistance measured by the bridge matched that of
the unknown RF power source. At that point, the DC power was equal
to the unknown RF power source's power.
-Chuck Harris Roy Morgan K1LKY since 1958 k1lky68@...
|
Re: Tips on repairing the stick attenuator in the HP86603A
I had asked if anyone was familiar with this type of atten. NOT the 8495 style, but a long stick. I guess no one reads. NO O rings.
Jeff
In a message dated 11/20/2018 7:02:42 PM Eastern Standard Time, glennmaillist@... writes:
Here is a video on repairing one of these attenuators:
The O-Rings are 2mm od x 1 mm id x 0.5mm thick.
Theses are used in watch making.
Hope this helps
Glenn
On 11/20/2018 6:31 PM, g lowrey wrote: > Hey Jeff. Have you measured one to check the size? I have several > sources that might be able to supply them - > 73, > Bo L. > > On 11/20/18, Jeff Kruth via Groups.Io <kmec= [email protected]> wrote: >> Hi All! >> Dont ask why, but I am resurrecting several HP 8660D generators with the >> HP86603A plugin. The attenuators are "sticky", get stuck in a certain >> position. If you have experience with this exact type of stick attenuator >> (long silver block) with the 3 - 40 dB, 20 dB, & 10 dB sections and can >> advise how to make a reliable repair, I would love to hear about it. Several >> that I cleaned the solenoid shafts on seemed to be working only to stick >> again. I do not know how to search the archives as well, can someone >> advise?Thanks!73Jeff Kruth >> >> >> >> > > > -- ----------------------------------------------------------------------- Glenn Little? ? ? ? ? ? ? ? ARRL Technical Specialist? QCWA? LM 28417 Amateur Callsign:? WB4UIV? ? ? ? ? ? wb4uiv@...? ? AMSAT LM 2178 QTH:? Goose Creek, SC USA (EM92xx)? USSVI LM? NRA LM? SBE ARRL TAPR "It is not the class of license that the Amateur holds but the class of the Amateur that holds the license"
|
Re: Tips on repairing the stick attenuator in the HP86603A
NOT O Rings. Different design than the small flat guys.
In a message dated 11/20/2018 5:32:51 PM Eastern Standard Time, danrae@... writes:
On 11/20/2018 1:48 PM, Jeff Kruth via Groups.Io wrote:
Hi All!
Dont ask why, but I am resurrecting several HP 8660D generators with the HP86603A plugin. The attenuators are "sticky", get stuck in a certain position. If you have experience with this exact type of stick attenuator (long silver block) with the 3 - 40 dB, 20 dB, & 10 dB sections and can advise how to make a reliable repair, I would love to hear about it. Several that I cleaned the solenoid shafts on seemed to be working only to stick again. I do not know how to search the archives as well, can someone advise?
Sounds like the universal problem of decaying O-rings Jeff.? They are easier to replace than source. Dan
|
Re: Readings from 436A power meter using 82357B USB-GPIB?
Try addressing another device?? (Even one that doesn’t exist...)
Dave B (G0WBX)
Re: Readings from 436A power meter
using 82357B USB-GPIB?
From: Staffan
Date: Tue, 20 Nov 2018 10:26:07 PST
Hello,
Absolutely - just how to do this on the 82357B? Hopefully very
simple, but seems not to be available on the interactive IO. Any
hints would be very much appreciated!
Regards,
? Staffan
--
Created on and sent from a Unix like PC running and using free and open source software.
::
|
Re: HP8555A attenuator switching characteristics - notes and questions
Hi Ed, The output pulse is inhibited while the switch is rotating by?the pulse from?contact 4F on S1 (attenuator level) this feeds an RC network R18/C4 and Q2 on A7. If you turn the switch too fast the pulse is not generated. The pulse signal is narrower than the?coil circuit connection time due to differing contact widths.?Its explained in the service manual  Robert G8RPI.
|
Paul Bicknell
David C. Partridge
jim