From:[email protected] <[email protected]>
On Behalf Of Steve - Home Sent: Saturday, October 10, 2020 11:18 AM To:[email protected] Subject: Re: [HP-Agilent-Keysight-equipment] HP435 measuring head? kW's?
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At that price for the switch, my 11683A probably needs to be in the locked cabinet!
Steve
WB0DBS
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On Oct 10, 2020, at 12:46 PM, Dave Smith W6TE <w6te@...> wrote:
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Building a 11683A isn¡¯t as simple as using an old 8481A and a few precision resistors. The range switch in the HP 11683A is not your run-of-the-mill SP 10 pos rotary switch. HP used a very low resistance contacts in the switch. In fact,
there¡¯s a procedure in the 11683A¡¯s manual for checking the integrity of the switch. The switch has an in house part number and Keysight lists the switch at $3.000!
On Sat, Oct 10, 2020 at 7:07 AM Tom Holmes <tholmes@...> wrote:
By the way, what is involved in calibrating a power meter, not the sensor?
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An 11683A, 432A plus 478A-H75 sensor, a counter and a DMM.
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11683A is rare, but you can make one from a dead 8481A (and there are plenty of those around):
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Then you just need a stable voltage source in the range of a few hundred uV to 15.8 V.
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I made one and using a Fluke 343A as a voltage source and 34461A to measure the voltage, my 346A gave readings well within specs.
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Calibrating the power reference is difficult... it requires the H75 option for the 478A sensor (good luck finding that) and a somewhat complicated procedure involving measuring voltages from the 432A.