Yes. I (and everyone else here) uses decibels every day, but isn't it
odd that we use 1/10th of a Bel as a "base unit" of sorts? We talk
about 0.1dB or 0.01dB all the time, but why not a centiBel or a milliBel?
The common use of 1/10th probably has its roots in telephony (as the
unit itself does) for some very real-world reason, but it still seems
odd that it took hold.
-Dave
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On 08/25/2018 10:58 AM, Leon Robinson wrote:
Lets not forget deci.
Sent from K5JLR
-------- Original message --------
From: Gedas <w8bya@...>
Date: 08/25/2018 9:03 AM (GMT-06:00)
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 8656B
Hi Brian, do you remember from a long time ago when a 8pF cap would be
labeled as a 8 mmF on the schematic.
Gedas, W8BYA
Gallery at
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 8/25/2018 2:54 AM, Brian wrote:
Hello Dave,
?
I think that avoiding use of mF is for the reason that a long time
ago, ie, when I was young, a capacitor marked 8 mF was known to be 8
microFarad. The use of uF is a Johnny come lately, with the emergence
of SI multipliers. Easy to write the Greek mu, but not so easy to type
on the early QWERTY keyboards with early versions of word-processing
software. So, rather than confuse older people, the multiplier m for
capacitance is generally avoided.
?
73 de Brian, VK2GCE
?
*From:*[email protected]
[mailto:[email protected]] *On Behalf Of *Dr.
David Kirkby from Kirkby Microwave Ltd
*Sent:* Saturday, 25 August 2018 3:40 PM
*To:* [email protected]
*Subject:* Re: [HP-Agilent-Keysight-equipment] HP 8656B
?
On Fri, 24 Aug 2018, 06:38 Kuba Ober, <kuba@...
<mailto:kuba@...>> wrote:
How big is that cap, size-wise? It¡¯s unlikely to be a
supercapacitor for such voltage in anything older than a few years
or so, I¡¯d bet. It¡¯s a typo in the PL, and a common use of M for
micro. Happens all the time. You¡¯re looking at 24,000uF @ 40V.?
?
It is strange why mF? are rarely used. We use mV, mA, m ohm, mH, mm,
but when it comes to capacitors one uses? fF, pF, nF, uF and farads,
but rarely mF.?
?
A capacitor of 0.022? F is rarely called 22 mF, but usually 22,000 uF.?
?
When I use my HP 4284A LCR meter, I have to stop and think when it
shows a result in mF.?
?
I can only guess at one time capacitors usually had values of less
than 1000 uF, so people used uF, and never changed
?
We don't tend to use Mm either. A distance would normally be quoted as
4000 km rather than 4 Mm.?
?
Dave.?
--
Dave McGuire, AK4HZ
New Kensington, PA
Dave McGuire