Author Topic: Is this the proper way to calibrate a new rig expert?  (Read 1775 times)

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Offline steeleTopic starter

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Is this the proper way to calibrate a new rig expert?
« on: October 19, 2021, 06:38:56 pm »
Is this the proper way to calibrate a new rig expert? I have an older aa30 and have never tired this route

https://youtu.be/PYi_4-BYKFQ
 

Offline mendip_discovery

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #1 on: October 19, 2021, 08:55:25 pm »
 :palm: Cor he is a little full of himself.

I would say no. Yes, it does work but its not as good as having a set of connectors made up with an open, short and 50Ω load.

The Fluke already has a spec of 1% + 5 digits so at 50Ω it could be 49.0Ω or 51.0Ω so that could cause the readings to be off its not a good sign.
« Last Edit: October 19, 2021, 09:02:54 pm by mendip_discovery »
Motorcyclist, Nerd, and I work in a Calibration Lab :-)
--
So everyone is clear, Calibration = Taking Measurement against a known source, Verification = Checking Calibration against Specification, Adjustment = Adjusting the unit to be within specifications.
 

Offline Mark19960

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #2 on: October 22, 2021, 07:02:17 am »
 :palm:
No way.

Squeezing the connector with a pair of needle nose pliers to get a short?  :palm:
Keeping in mind that you are performing a calibration to set the measurement plane of the instrument.
That means all three measurements have to be done wherever that is.

You have the open...  it's just open. It's not capped but .. ok. it will work in a pinch.
The short is a pair of needle nose pliers being used to squeeze the connector and scarring it up. But is it a real short?
The load... well its coax running off to who knows where.

So.. where does the measurement plane end up being?
Well... somewhere?

Calibrations don't matter much when you either cannot perform them or abuse the equipment.
That is not how you do things "in the real world" as the video is titled....
 :palm:
 

Offline Denny Wa

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #3 on: October 22, 2021, 08:06:06 am »
First thing I would say is, this guy should not have any, "customers".  In the correct users hands, these antenna analyzer (all the brands) are very powerful RF Network Analyzers.  I use one professionally to test RF Matching Units from semiconductor processing tools, but I also have a VNA with known good SLOT (short, open, load, thru) calibration loads to compare to, my SARK-110 gives good results.  Back to the posted question, this guy does not have a clue, knows nothing about transmission line theory, and thinks Mr. Smith (and his chart) are Tik Tok posters.

You can do a very good calibration with home made calibration loads for very little money, or no money.  But not what this guy is doing.  Do search for DIY VNA loads, or buy some from China.  You don't need to spend USD $1000 or much much more.  Then enter your turner schematic into one of the many RF Network simulators and have fun, you will be impressed with how powerful these devices are.  Also, make a 3:1 mismatch load and watch how different lengths of coax cable will walk the measurement point around the smith chart.
« Last Edit: October 22, 2021, 08:13:17 am by Denny Wa »
 

Offline mendip_discovery

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #4 on: October 24, 2021, 05:20:40 pm »
:palm:
No way.

Squeezing the connector with a pair of needle nose pliers to get a short?  :palm:
Keeping in mind that you are performing a calibration to set the measurement plane of the instrument.
That means all three measurements have to be done wherever that is.

You have the open...  it's just open. It's not capped but .. ok. it will work in a pinch.
The short is a pair of needle nose pliers being used to squeeze the connector and scarring it up. But is it a real short?
The load... well its coax running off to who knows where.

So.. where does the measurement plane end up being?
Well... somewhere?

Calibrations don't matter much when you either cannot perform them or abuse the equipment.
That is not how you do things "in the real world" as the video is titled....
 :palm:

I have been asked to calibrate short, open, load connectors before but shied away from it as I did do some YT watching and if I wasn't careful I could end up in muddy waters. I have a plan to get a VNC thing for checking my antennas I have here and I will look at making some loads for it. There are plenty of good YT videos out there but also a lot of rubbish ones, much like advice found on forums. ;-)
Motorcyclist, Nerd, and I work in a Calibration Lab :-)
--
So everyone is clear, Calibration = Taking Measurement against a known source, Verification = Checking Calibration against Specification, Adjustment = Adjusting the unit to be within specifications.
 

Offline Bud

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #5 on: October 24, 2021, 06:28:00 pm »
The name of the channel is "Fine tune CB shop". Is anything else you guys need explained?  >:D
Facebook-free life and Rigol-free shack.
 

Online bdunham7

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #6 on: October 24, 2021, 06:37:09 pm »
So easy a cave man can do it. 
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Offline Mark19960

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #7 on: October 25, 2021, 03:05:27 am »
This guy is worth a post in the metrology section all of it's own on how not to do things. but I don't want the real metrologists in here to laugh literally to death.
But alas, it's just rubbish wasting space on the server  ;D

There are people in the states that flock to him and think of him as an authoritive source. Such is life in the American radio communities.
He portrays himself as the jesus of radio. He has a totalitarian attitude that certain people clearly gravitate towards.
There was a lost post in the ham radio section I think entitled "what ever happened to ham radio" and it's people like this that happened to it.
I have links to videos that I keep on how not to do something, and his videos are an excellent source of "ignorance on fire" material.

The lack of using decent open/short/load for someone that waves a dubious calibration paper around screaming "I HAVE NIST CABLIBRATIONS!" and "I AM NIST CERTIFIED"!
 :palm: It's the antithesis.....

He has a NIST certified BG7TBL GPSDO!
WOW! When did NIST start to "certify" those?
It's in this video:


I have to admit the number of laughs I have gotten out of this cheeky chappy are quite numerous.

I him a "nothing to see here, move along" type of person.
He has been featured more than a few times mostly for peddling snake oil transistors or making outlandish claims like the "one one thousandth of one microvolt" CB radio receiver.

He says that NIST certified his "bench" and when asked what the "bench" is... yes.... the wooden table is "NIST Certified" according to this fella.

 :palm:
 

Offline Bud

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Re: Is this the proper way to calibrate a new rig expert?
« Reply #8 on: October 25, 2021, 04:24:29 am »
In CB land anything is possible  :-+
Facebook-free life and Rigol-free shack.
 


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