Lets not forget deci.
Sent from K5JLR
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-------- 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
?
?
On Fri, 24 Aug 2018, 06:38 Kuba
Ober, <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.?
|
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:
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Show quoted text
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
?
?
On Fri, 24 Aug 2018, 06:38 Kuba
Ober, <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.?
|
A 'mil' is also used in US money. It is 1/1000 of a dollar and used for tax rates along with other special transactions.
Michael A. Terrell
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-----Original Message----- From: Adrian <Adrian@...>
Sent: Aug 25, 2018 4:22 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 8656B
So I am of an age that I grew up using Imperial measures and pre-decimal money. I have also lived and worked both sides of the Atlantic and in most things I am almost bi-lingual!
The one thing that still trips me up (if I'm not careful) is that in the States, in an engineering shop, a request to "take a couple of mil off that face" means they would take off two thousandths of an inch but in a UK shop they would take a couple of millimetres off!
In the UK 1/1000 of an inch is a 'thou', so I guess the use of 'mil' is a hangover from the Roman occupation of North America?
Adrian
|
So I am of an age that I grew up using Imperial measures and pre-decimal money. I have also lived and worked both sides of the Atlantic and in most things I am almost bi-lingual! The one thing that still trips me up (if I'm not careful) is that in the States, in an engineering shop, a request to "take a couple of mil off that face" means they would take off two thousandths of an inch but in a UK shop they would take a couple of millimetres off! In the UK 1/1000 of an inch is a 'thou', so I guess the use of 'mil' is a hangover from the Roman occupation of North America? Adrian On 8/25/2018 12:56 AM, Dave McGuire wrote: ...'cause THAT'S practical in the 20th century..
-Dave M is the Roman numeral for 1000. Dave Wise
|
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
?
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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@...> 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.?
|
Dr. David Kirkby from Kirkby Microwave Ltd
On Fri, 24 Aug 2018, 06:38 Kuba Ober, < 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.?
|
On 08/24/2018 08:34 PM, Harvey White wrote: I never did understand the point of the 0F13 notation and have never
particular cared for it. Arbitrarily moving the units into the decimal
position seems like a very random thing to do. one of the difficulties with the 0.xxx notation is leaving off the
zero, or watching the decimal point go away under a bit of use.
Sure, I can't disagree with that. The advantage is that the decimal separator is kinda obvious. It's
actually easier to look at an SMD resistor and read it if it were
using the #R# notation. Yebbut...moving the unit there? Why not just replace the period with something more visible? Even 'X' would do. Even '/'. But don't move the unit...that belongs to the right of the number. On the other hand, a lot of it is what you're used to. Yes, mostly. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
|
On Fri, 24 Aug 2018 16:25:05 -0400, you wrote: On 08/24/2018 09:13 AM, Kuba Ober wrote:
I somehow didn’t run into the xxxF notation, where the first digit is 10^-1. Writing 13mF as 013F would be be IMHO crazy. I’d understand 0F13. But of course I didn’t notice the decimal point in front of the zero in Chuck McC’s post — he seemingly was aware that it was not 13F, perhaps. Only one mention had the correct scaling. I think that in this day and age, all electrolytics can afford to have the capacity written in SI units with international standard scale suffixes. With a zero leading the decimal point, if applicable. It’s extremely easy to misread, say .200F as 200F :) Especially after a long day. I imagine over the years some lives and/or lots of money must have been lost to mishaps of that kind. A space probe, even :) I never did understand the point of the 0F13 notation and have never
particular cared for it. Arbitrarily moving the units into the decimal
position seems like a very random thing to do. one of the difficulties with the 0.xxx notation is leaving off the zero, or watching the decimal point go away under a bit of use. The advantage is that the decimal separator is kinda obvious. It's actually easier to look at an SMD resistor and read it if it were using the #R# notation. On the other hand, a lot of it is what you're used to. Harvey
But a leading zero makes 0.013F pretty readable, IMO.
The real problems come in, as Chuck pointed out, when the industry
does things like "MFD". Gads am I glad those days are over!
-Dave
|
...'cause THAT'S practical in the 20th century..
-Dave
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On 08/24/2018 07:46 PM, Dave Wise wrote: M is the Roman numeral for 1000.
Dave Wise
On Aug 24, 2018, at 4:29 PM, Peter Gottlieb <hpnpilot@...> wrote:
This is also done in finance where M is 1000 and MM is million. Really odd!
On 8/24/2018 7:19 PM, Brad Thompson wrote:
On 8/24/2018 4:25 PM, Dave McGuire wrote:
<snip>
I never did understand the point of the 0F13 notation and have never
particular cared for it. Arbitrarily moving the units into the decimal
position seems like a very random thing to do.
But a leading zero makes 0.013F pretty readable, IMO.
The real problems come in, as Chuck pointed out, when the industry
does things like "MFD". Gads am I glad those days are over! Hello--
Another pitfall from the "good old days" awaits the beginning
restorer or repairer who examines the schematics of certain
older (tubed) radios. Some manufacturers used "M" as a
multiplier of 1,000 in resistor values.
For example, I'm looking at a schematic for a 1930s Grunow
model 1291 receiver in which various resistors sport labels of
"ohms", "M" and "megohms".
Fortunately, a little knowledge of circuit design would tell you
that using a 47M (megohm) plate resistor in an audio-amplifier
stage would be highly unlikely.
73--
Brad AA1IP
--
Dave McGuire, AK4HZ
New Kensington, PA
|
M is the Roman numeral for 1000.
Dave Wise
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On Aug 24, 2018, at 4:29 PM, Peter Gottlieb <hpnpilot@...> wrote:
This is also done in finance where M is 1000 and MM is million. Really odd!
On 8/24/2018 7:19 PM, Brad Thompson wrote:
On 8/24/2018 4:25 PM, Dave McGuire wrote:
<snip>
I never did understand the point of the 0F13 notation and have never
particular cared for it. Arbitrarily moving the units into the decimal
position seems like a very random thing to do.
But a leading zero makes 0.013F pretty readable, IMO.
The real problems come in, as Chuck pointed out, when the industry
does things like "MFD". Gads am I glad those days are over! Hello--
Another pitfall from the "good old days" awaits the beginning
restorer or repairer who examines the schematics of certain
older (tubed) radios. Some manufacturers used "M" as a
multiplier of 1,000 in resistor values.
For example, I'm looking at a schematic for a 1930s Grunow
model 1291 receiver in which various resistors sport labels of
"ohms", "M" and "megohms".
Fortunately, a little knowledge of circuit design would tell you
that using a 47M (megohm) plate resistor in an audio-amplifier
stage would be highly unlikely.
73--
Brad AA1IP
|
This is also done in finance where M is 1000 and MM is million. Really odd!
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On 8/24/2018 7:19 PM, Brad Thompson wrote: On 8/24/2018 4:25 PM, Dave McGuire wrote:
<snip>
?? I never did understand the point of the 0F13 notation and have never
particular cared for it.? Arbitrarily moving the units into the decimal
position seems like a very random thing to do.
?? But a leading zero makes 0.013F pretty readable, IMO.
?? The real problems come in, as Chuck pointed out, when the industry
does things like "MFD".? Gads am I glad those days are over! Hello--
Another pitfall from the "good old days" awaits the beginning
restorer or repairer who examines the schematics of certain
older (tubed) radios. Some manufacturers used "M" as a
multiplier of 1,000 in resistor values.
For example, I'm looking at a schematic for a 1930s Grunow
model 1291 receiver in which various resistors sport labels of
"ohms", "M" and "megohms".
Fortunately, a little knowledge of circuit design would tell you
that using a 47M (megohm) plate resistor in an audio-amplifier
stage would be highly unlikely.
73--
Brad? AA1IP
|
On 8/24/2018 4:25 PM, Dave McGuire wrote: <snip> I never did understand the point of the 0F13 notation and have never
particular cared for it. Arbitrarily moving the units into the decimal
position seems like a very random thing to do.
But a leading zero makes 0.013F pretty readable, IMO.
The real problems come in, as Chuck pointed out, when the industry
does things like "MFD". Gads am I glad those days are over! Hello-- Another pitfall from the "good old days" awaits the beginning restorer or repairer who examines the schematics of certain older (tubed) radios. Some manufacturers used "M" as a multiplier of 1,000 in resistor values. For example, I'm looking at a schematic for a 1930s Grunow model 1291 receiver in which various resistors sport labels of "ohms", "M" and "megohms". Fortunately, a little knowledge of circuit design would tell you that using a 47M (megohm) plate resistor in an audio-amplifier stage would be highly unlikely. 73-- Brad AA1IP
|
I'm having some problems with some oscillations in the low noise
amplifier of my 11729C with serial prefix 2329A.
The frequency is around 27MHz, and I beleve it is from the pre-amp
section of the low noise section. Mixing products of this are also
appearing as low frequency modulations on the detected noise.
Since my testset is older than the available manuals (2509A), I was
hoping someone had one for the earlier version, either for sale or
available for scan?
As far as I can determine, all the ferrite beads are in place, as well
as the decoupling capacitor, although I question the usage of only
electrolytics as decoupling in a amplifier with response 10Hz-25MHz.
The transistors used has a Ft of 2.4GHz so I guess a next test may be
to parallel the electrolytics with some smaller ceramic capacitors.
Have anyone seen this problem before? any hint on where to go forward
is appreciated.
BR.
Thomas.
--
With Best regards, Thomas S. Knutsen.
Please avoid sending me Word or PowerPoint attachments.
|
On Fri, Aug 24, 2018 at 1:25 PM Dave McGuire < mcguire@...> wrote: ? I never did understand the point of the 0F13 notation and have never
particular cared for it.? Arbitrarily moving the units into the decimal
position seems like a very random thing to do.
? But a leading zero makes 0.013F pretty readable, IMO.
It was almost certainly done because decimal points would disappear, or a spec of dust would turn into a decimal point, especially on those parts lists that came from micro-fiche.? It's pretty hard to mess up 0F013.? I remember the change with resistors where 2.2K became 2K2.? It was annoying at first, but I got used to it.? It's perhaps debatable that the current practice of using the final digit as the number of zeros to add is better or worse.? So now we have 2.2K resistors marked 222... and back in capacitor land, 0.1uF marked 104.? Now which three digit number on this capacitor is its value... or is it the date code?
|
On 08/24/2018 09:13 AM, Kuba Ober wrote: I somehow didn’t run into the xxxF notation, where the first digit is 10^-1. Writing 13mF as 013F would be be IMHO crazy. I’d understand 0F13. But of course I didn’t notice the decimal point in front of the zero in Chuck McC’s post — he seemingly was aware that it was not 13F, perhaps. Only one mention had the correct scaling. I think that in this day and age, all electrolytics can afford to have the capacity written in SI units with international standard scale suffixes. With a zero leading the decimal point, if applicable. It’s extremely easy to misread, say .200F as 200F :) Especially after a long day. I imagine over the years some lives and/or lots of money must have been lost to mishaps of that kind. A space probe, even :) I never did understand the point of the 0F13 notation and have never particular cared for it. Arbitrarily moving the units into the decimal position seems like a very random thing to do. But a leading zero makes 0.013F pretty readable, IMO. The real problems come in, as Chuck pointed out, when the industry does things like "MFD". Gads am I glad those days are over! -Dave -- Dave McGuire, AK4HZ New Kensington, PA
|
Re: 8970B Noise figure unit
No, sorry, it was over a year ago.?
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On Aug 24, 2018, at 1:01 PM, kevin kearns < kkyahoo@...> wrote:
Peter, Any recall of the physical size?
?
Kevin
----- Original Message -----
Sent: Friday, August 24, 2018 5:27
PM
Subject: Re:
[HP-Agilent-Keysight-equipment] 8970B Noise figure unit
I have, but it was one I had already so don’t remember the
number. These kinds of fans are readily available, and the newer ones have a
reduced noise level for the same CFM and backpressure.?
On Aug 24, 2018, at 11:41 AM, kevin kearns < kkyahoo@...>
wrote:
Has anyone changed their fan on the 8970? Mine is very noisy and likely
to fail soon. Original is a Dryco 411M-11, 30CFM, 115V.
Kevin
|
Re: 8970B Noise figure unit
?
Peter, Any recall of the physical size?
?
Kevin
----- Original Message -----
Sent: Friday, August 24, 2018 5:27
PM
Subject: Re:
[HP-Agilent-Keysight-equipment] 8970B Noise figure unit
I have, but it was one I had already so don’t remember the
number. These kinds of fans are readily available, and the newer ones have a
reduced noise level for the same CFM and backpressure.?
On Aug 24, 2018, at 11:41 AM, kevin kearns < kkyahoo@...>
wrote:
Has anyone changed their fan on the 8970? Mine is very noisy and likely
to fail soon. Original is a Dryco 411M-11, 30CFM, 115V.
Kevin
|
Late into this thread, may be misunderstanding the issue.
Reads like you need a 20V 24,000uF axial cap to fit in a 104 x
28mm space on a pcb?
Digi and Mouser both have a 15,000 uF axial 25V part with a
3700mA ripple that is 50x22mm - would not look 'elegant' but two
of those could be fitted in parallel fairly easily in the space.
If it is actually on the 5V line then Digi have a 22,000uF 16V
part with 3.7A ripple that would probably work fine on it's own,
that one is also small at 51x22mm.
Adrian
On 8/24/2018 5:47 PM, Chuck wrote:
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Ok. thanks for the info...........BUT
?
I removed the Cap and have it in front of me as I type:
?
It says on the can:
?
Sprague
0180-3209
53D190
24000UF20VDC
-10+75%
+85C 9050H
Made in USA
?
The ONLY difference is on the Schemaitc and part list it says
.013F. (ie: 13000) so there must have been a up-grade I have not
found.
?
The size is:
?
4.12-in long (104.6mm)
1.128-in diam. (28.66mm)
with Axial leads
?
All the ones I have found are for screw mount and are WAY to
large to fit on the A10 board.
?
Thanks,
?
Chuck McClurg
Communications, Ltd
Carson City, NV
N7UVZ
?
|
Re: 8970B Noise figure unit
I have, but it was one I had already so don’t remember the number. These kinds of fans are readily available, and the newer ones have a reduced noise level for the same CFM and backpressure.?
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On Aug 24, 2018, at 11:41 AM, kevin kearns < kkyahoo@...> wrote: Has anyone changed their fan on the 8970? Mine is very noisy and likely to fail soon. Original is a Dryco 411M-11, 30CFM, 115V.
Kevin
|
Change to P/N 0180-3209 starting w/ s/n prefix 2425A, 24000uF, 20VDC, Service Manual p/n 08656-90214- April 1986, rev 20 Oct 87.
Dave
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On Fri, Aug 24, 2018 at 08:49 AM, Chuck wrote:
Ok. thanks for the info...........BUT
?
I removed the Cap and have it in front of me as I type:
?
It says on the can:
?
Sprague
0180-3209
53D190
24000UF20VDC
-10+75%
+85C 9050H
Made in USA
?
The ONLY difference is on the Schemaitc and part list it says .013F. (ie: 13000) so there must have been a up-grade I have not found.
?
The size is:
?
4.12-in long (104.6mm)
1.128-in diam. (28.66mm)
with Axial leads
?
All the ones I have found are for screw mount and are WAY to large to fit on the A10 board.
?
Thanks,
?
Chuck McClurg
Communications, Ltd
Carson City, NV
N7UVZ
|
Michael A. Terrell
Brian
Dave McGuire