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For those of you who possess the older (hopefully working and accurate) 478A coaxial thermistor mount it might come as a surprise that the price of the present replacement ¨C the Keysight 8478B mount ¨C has again risen a few hundred $$ to $14,100.
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That is a real incentive to treat your present mount with kindness and respect and not let it roll off of the bench.
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Greg
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OMG, who would have thought......................
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It is directed at a captive audience. This piece is used as the transfer standard for making power measurement calibrations and is required for certain procedures. If you want to play in a certain arena, ou hve to have one. Obviously, HP does not sell too many of them which also leads to the huge cost.
Cheers!
bruce
Quoting Ken Eckert <eckertkp@...>:
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OMG, who would have thought......................
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first of you have to consider that the 8478B just as the older 478 series requires a lot of manual assembly steps as it was designed in a time when there was no such thing as surface mount parts or automated assembly . one also has to consider that the QTY of those sold by keysight now is by far less than it was 10 or 20 years back ,? as bruce already pointed out those sensors nowadays are not mainstream anymore but rather used in calibration labs?
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i wouldnt call it a transfer standard , weinschel/tegam makes sensors that use the same principle that are heated (1109/1111)? that are used with system 2 units to calibrate sensors , they are outrageously expensive?
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On 5/26/22 16:10, Lothar baier wrote: i wouldnt call it a transfer standard , weinschel/tegam makes sensors that use the same principle that are heated (1109/1111)? that are used with system 2 units to calibrate sensors , they are outrageously expensive They certainly can be, and certainly are, used as transfer standards. Further, NIST will calibrate them. (they won't calibrate any other type of RF power sensor, unless something has changed very recently) -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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I certainly would call $14K outrageously expensive.
Cheers!
Bruce
Quoting Lothar baier <Lothar@...>:
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i wouldnt call it a transfer standard , weinschel/tegam makes sensors that use the same principle that are heated (1109/1111)? that are used with system 2 units to calibrate sensors , they are outrageously expensive
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I actually have one of these and treat it VERY carefully whenever I use it - which is infrequently
Cheers!
Bruce
Quoting Lothar baier <Lothar@...>:
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first of you have to consider that the 8478B just as the older 478 series requires a lot of manual assembly steps as it was designed in a time when there was no such thing as surface mount parts or automated assembly . one also has to consider that the QTY of those sold by keysight now is by far less than it was 10 or 20 years back ,? as bruce already pointed out those sensors nowadays are not mainstream anymore but rather used in calibration labs
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I haven¡¯t seen any 8478B used as transfer standard , we used them with some special option to calibrate the 50MHz reference on 43x series meters , for sensor calibration we used a weinschel system2 , Yes NIST - if you can afford it - will calibrate any sensors that are using a self nulling bridge circuit which certainly includes the 8478B as well as the weinschel sensors
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Dave McGuire via groups.io Sent: Thursday, May 26, 2022 3:31 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] HP/Agilent/Keysight 8478B thermistor mount On 5/26/22 16:10, Lothar baier wrote: i wouldnt call it a transfer standard , weinschel/tegam makes sensors
that use the same principle that are heated (1109/1111)? that are used
with system 2 units to calibrate sensors , they are outrageously
expensive They certainly can be, and certainly are, used as transfer standards. Further, NIST will calibrate them. (they won't calibrate any other type of RF power sensor, unless something has changed very recently) -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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This one came from an auction at McDonnell Douglas plant in St. Louis - It was in their standards lab - a long time ago.
AFIK the "B" version is the only one available from HP
Cheers!
Quoting Lothar baier <Lothar@...>:
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I haven¡¯t seen any 8478B used as transfer standard , we used them with some special option to calibrate the 50MHz reference on 43x series meters , for sensor calibration we used a weinschel system2 , Yes NIST - if you can afford it - will calibrate any sensors that are using a self nulling bridge circuit which certainly includes the 8478B as well as the weinschel sensors
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Dave McGuire via groups.io
Sent: Thursday, May 26, 2022 3:31 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP/Agilent/Keysight 8478B thermistor mount
On 5/26/22 16:10, Lothar baier wrote:
i wouldnt call it a transfer standard , weinschel/tegam makes sensors
that use the same principle that are heated (1109/1111)? that are used
with system 2 units to calibrate sensors , they are outrageously
expensive They certainly can be, and certainly are, used as transfer standards.
Further, NIST will calibrate them. (they won't calibrate any other type of RF power sensor, unless something has changed very recently)
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
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If it was used in a standards lab it more than likely has option H01 which guarantees a VSWR < 1.05 at 50MHz , usually either the 8478B-H01 or 478A-H75 or H76 are used for the power level accuracy test for the 50MHz calibrator on HP Power meters
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Bruce via groups.io Sent: Thursday, May 26, 2022 5:32 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] HP/Agilent/Keysight 8478B thermistor mount This one came from an auction at McDonnell Douglas plant in St. Louis - It was in their standards lab - a long time ago. AFIK the "B" version is the only one available from HP Cheers! Quoting Lothar baier <Lothar@...>: I haven¡¯t seen any 8478B used as transfer standard , we used them
with some special option to calibrate the 50MHz reference on 43x
series meters , for sensor calibration we used a weinschel system2 ,
Yes NIST - if you can afford it - will calibrate any sensors that are
using a self nulling bridge circuit which certainly includes the 8478B
as well as the weinschel sensors
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of Dave McGuire
via groups.io
Sent: Thursday, May 26, 2022 3:31 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP/Agilent/Keysight 8478B
thermistor mount
On 5/26/22 16:10, Lothar baier wrote:
i wouldnt call it a transfer standard , weinschel/tegam makes sensors
that use the same principle that are heated (1109/1111)? that are
used with system 2 units to calibrate sensors , they are outrageously
expensive They certainly can be, and certainly are, used as transfer standards.
Further, NIST will calibrate them. (they won't calibrate any other
type of RF power sensor, unless something has changed very recently)
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
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Yes 8478B is a transfer power standard for 7mm connectors . It¡¯s very stable , the matching is not the best but with a good VNA are used as transfer standard on most national lab. The efficiency are measured on microcalorimeter with extreme accuracy close to as remember .1% Ing. Patricio A. GrecoTaller Aeron¨¢utico de Reparaci¨®n 1B-349Organizaci¨®n de Mantenimiento Aeron¨¢utico de la Defensa OMAD-001Gral. Mart¨ªn Rodr¨ªguez 2159San Miguel (1663)Buenos AiresT:?+5411-4455-2557F:?+5411-4032-0072
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On 26 May 2022, at 18:54, Lothar baier <Lothar@...> wrote:
? I haven¡¯t seen any 8478B used as transfer standard ?, we used them with some special option to calibrate the 50MHz reference on 43x series meters , for sensor calibration we used a weinschel system2 , Yes NIST - if you can afford it - ?will calibrate any sensors that are using a self nulling bridge circuit which certainly includes the 8478B as well as the weinschel sensors -----Original Message-----From: [email protected] <[email protected]> On Behalf Of Dave McGuire via groups.ioSent: Thursday, May 26, 2022 3:31 PMTo: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] HP/Agilent/Keysight 8478B thermistor mountOn 5/26/22 16:10, Lothar baier wrote:i wouldnt call it a transfer standard , weinschel/tegam makes sensors
that use the same principle that are heated (1109/1111)? that are used
with system 2 units to calibrate sensors , they are outrageously
expensive
??They certainly can be, and certainly are, used as transfer standards. ?Further, NIST will calibrate them. (they won't calibrate any other type of RF power sensor, unless something has changed very recently) ???????????-Dave--Dave McGuire, AK4HZNew Kensington, PA
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Dave McGuire
Patricio A. Greco