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Hate to burst your bubble Dave, but the HP-3561A , in their
documentation, refers to the low frequency coverage (micro Hz) as
uHz, and how about kHz. So, yeah, mHz for "mili Hz" works for me
but hey I'm only a retired technician. BTW electron flow is from
(-) negative to (+) positive, but the engineers I worked with
called it "hole flow". ??? I guess they stand on an overhead
bridge and watch the spaces going the opposite way than the cars.
Clip from pdf of HP's 3561A:
Just sayin'
Mike C. Sand Mtn GA
On 5/16/2025 6:34 PM, W0LEV via
groups.io wrote:
toggle quoted message
Show quoted text
Yea, Don, get the newbies to
use proper abbreviations!? I've called it out many times, but
it seems to fall on deaf ears and clearly never reaches the
gray matter.? What really gets my goat is "mhz".? What is
mhz?? MilliHertz?? Nothing the typical amateur deals with
delves into the milliHertz range!? Further the proper
abbreviation for Hertz is Hz, not hz!? Should I give up?
Dave - W?LEV
On Fri, May 16, 2025 at
5:49?PM Donald S Brant Jr via <dsbrantjr= [email protected]>
wrote:
On Thu, Mar 20, 2025 at 04:17 PM, sdegroff wrote:
All references when not given are 0db = 1w
My observation is that very few people use units of dbW even
when working at high power, dbm (relative to 1 milliwatt)
being far more common.?
If a colleague started using dBW I would ask them why as
I see no good reason for it, it is likely to cause
confusion.? Like 1000X level confusion.
?
In the RF world, if something is written as "xdB" it is
NOT a power level, it is a power ratio, or actually 10log of
that ratio.?
?
The TinySA power specs all use dBm AFAIK.
73, Don N2VGU
--
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Yes, I have one generator that goes to ?Hz.? But I'm not a typical ham by any means!? If you build yourself a seismometer, you're in the mHz region.
Dave - W?LEV
Hate to burst your bubble Dave, but the HP-3561A , in their
documentation, refers to the low frequency coverage (micro Hz) as
uHz, and how about kHz. So, yeah, mHz for "mili Hz" works for me
but hey I'm only a retired technician. BTW electron flow is from
(-) negative to (+) positive, but the engineers I worked with
called it "hole flow". ??? I guess they stand on an overhead
bridge and watch the spaces going the opposite way than the cars.
Clip from pdf of HP's 3561A:
Just sayin'
Mike C. Sand Mtn GA
On 5/16/2025 6:34 PM, W0LEV via
wrote:
Yea, Don, get the newbies to
use proper abbreviations!? I've called it out many times, but
it seems to fall on deaf ears and clearly never reaches the
gray matter.? What really gets my goat is "mhz".? What is
mhz?? MilliHertz?? Nothing the typical amateur deals with
delves into the milliHertz range!? Further the proper
abbreviation for Hertz is Hz, not hz!? Should I give up?
Dave - W?LEV
On Fri, May 16, 2025 at
5:49?PM Donald S Brant Jr via <dsbrantjr= [email protected]>
wrote:
On Thu, Mar 20, 2025 at 04:17 PM, sdegroff wrote:
All references when not given are 0db = 1w
My observation is that very few people use units of dbW even
when working at high power, dbm (relative to 1 milliwatt)
being far more common.?
If a colleague started using dBW I would ask them why as
I see no good reason for it, it is likely to cause
confusion.? Like 1000X level confusion.
?
In the RF world, if something is written as "xdB" it is
NOT a power level, it is a power ratio, or actually 10log of
that ratio.?
?
The TinySA power specs all use dBm AFAIK.
73, Don N2VGU
--
|
Dave, W0LEV, is correct. The metric prefixes are well-defined. See?
for a list of them. One of the ones that people screw up is milli (m) vs. mega (M). When mHz (or mhz) is typed instead of MHz, most of us can infer the correct prefix and unit. But in actual scientific and engineering work, accuracy in notation is very important, so we strive to use the correct notation. The difference between milli (m) and mega (M) is *nine* (10E9) orders of magnitude.
The unit abbreviation is also screwed up by many people. The unit "Hertz" is properly abbreviated as "Hz" and not "hz" and named after Heinrich Hertz, who was the first physicist to prove the existence of electromagnetic waves after Maxwell predicted them mathematically. We pay tribute to Hertz's pioneering work by capitalizing the abbreviation Hz. Other examples are J for Joule, W for Watt, O for Oersted, T for Telsa (the physicist, not the vehicle), V for volt, etc., etc., all named after the scientists who first discovered or identified the quantity in question. While many users of the tinysa are not engineers by vocation, they have to know or learn the technical principles involved with using spec ans and it behooves us (at least IMHO) to get the notation correct when communicating technical information.
There are other units the abbreviations for which people routinely mistype. The difference between "S" (Siemens) and "s" (seconds) comes to mind.
One of the basic techniques for solving mathematical equations in scientific work is to perform unit analysis as well as the mathematical calculation. Unit analysis involves ignoring the numbers and looking at the units to make sure that the units agree on both sides of the equation. If one starts with something such as "Volts/meter" on the LH side of the equation and unit analysis results in "meters/second" on the RH side of the calculation, one knows that one has miscalculated. Using the correct abbreviations for the units involved is key to accomplishing that effort.
The above is just my take on this stuff after working for 30+ years as an embedded systems design engineer in the IBM computer world of engineering. Worth 25 cents, taking into account inflation.
Hate to burst your bubble Dave, but the HP-3561A , in their
documentation, refers to the low frequency coverage (micro Hz) as
uHz, and how about kHz. So, yeah, mHz for "mili Hz" works for me
but hey I'm only a retired technician. BTW electron flow is from
(-) negative to (+) positive, but the engineers I worked with
called it "hole flow". ??? I guess they stand on an overhead
bridge and watch the spaces going the opposite way than the cars.
Clip from pdf of HP's 3561A:
Just sayin'
Mike C. Sand Mtn GA
On 5/16/2025 6:34 PM, W0LEV via
wrote:
Yea, Don, get the newbies to
use proper abbreviations!? I've called it out many times, but
it seems to fall on deaf ears and clearly never reaches the
gray matter.? What really gets my goat is "mhz".? What is
mhz?? MilliHertz?? Nothing the typical amateur deals with
delves into the milliHertz range!? Further the proper
abbreviation for Hertz is Hz, not hz!? Should I give up?
Dave - W?LEV
On Fri, May 16, 2025 at
5:49?PM Donald S Brant Jr via <dsbrantjr= [email protected]>
wrote:
On Thu, Mar 20, 2025 at 04:17 PM, sdegroff wrote:
All references when not given are 0db = 1w
My observation is that very few people use units of dbW even
when working at high power, dbm (relative to 1 milliwatt)
being far more common.?
If a colleague started using dBW I would ask them why as
I see no good reason for it, it is likely to cause
confusion.? Like 1000X level confusion.
?
In the RF world, if something is written as "xdB" it is
NOT a power level, it is a power ratio, or actually 10log of
that ratio.?
?
The TinySA power specs all use dBm AFAIK.
73, Don N2VGU
--
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Add to this list people who routinely mix up "B" for bytes and "b" for bits, especially in the networking part of the computer world.
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On Fri, May 16, 2025 at 11:04 AM, Adam Coate wrote:
Anyway, what can I do to discharge the voltage built up in my 3 foot SMA cable and HTOOL HT8 log periodic antenna? Grounding rod?
Short the SMA central pin with the outside of the SMA plug.
No ground needed.
--
Designer of the tinySA
For more info go to
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A GOOD PRACTICE:? Whenever I pick up the end of a coaxial cable, I always hold a finger across the end "shorting" the center conductor to the backshell before connecting it to anything.? Doesn't matter if the coax is connected to an outside antenna or laying on the bench.?
Most of the time I don't get any response.? But occasionally I get just a "bit" (***) of a surprise.? You just might get more of a surprise if the coax is connected to an outside antenna in a windstorm, rain, or snow!?? In either case, I've just saved the piece of equipment I was going to connect the coax to.
Dave - W?LEV?
On Fri, May 16, 2025 at 11:04 AM, Adam Coate wrote:
Anyway, what can I do to discharge the voltage built up in my 3 foot SMA cable and HTOOL HT8 log periodic antenna? Grounding rod?
Short the SMA central pin with the outside of the SMA plug.
No ground needed.
--
Designer of the tinySA
For more info go to
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Mike C.