Move the antenna further away. then use correction factors to calculate
what it would have been at the original distance.
Magnetic fields decrease as the inverse cube of the distance. So just apply
a correction factor to "boost" the amplitude back up. For example, twice
the distance away means
Sorry to post here but am running into a brick wall at trying to find out
something as simple as the resistivity and dielectric constant for skin!
Does anybody have a source? Need quick, please.
- Robert -
---
This message is from
Chris,
Fluorescent tubes are noisy anyway, but the old passive ballasts are
starting to be replaced with active "electronic" ballasts. Those electronic
widgets actually run at frequencies down near what you're using.
Electrically they can be EXTREMELY noisy. The US has no real restrictions.
A
They will deliver less powerabour 50/60 of what you expect.
The power supplies in those ovens are quite inexpensive and use a single
rectifying diode. When the voltage gets high enough, the microwave bursts
on for a short time. Thus, if operated from 50 Hz instead of 60 Hz, the
power will d
Did you find out what you need?
Somewhere around here I have the equations that closely approximate twisted
pair for 26 Awg and 28 Awg wire from DC to 10MHz. They were derived from
empirical modeling. You can make various approximations to simplify their
use.
That includes impedance, loss per
The accurate volume is about 1/3 by 1/3 of the outside dimensions. At least
that's my "measured" experience.
Just means one has to make a rather large Helmholtz for a large sensing
coil. And my recollection of most sensing coils in that range are that
they're over 1/2 meter in diameter. I've s
Actually, most meters average the waveform, then apply a rote formula
converting that average to an rms reading which is more likely to err on the
side of too low a reading.
For a square wave it will read too high by 6% (actually worked this out, but
forgot the actual number, but you have the ide
We made a probe using rigid coax with its built in SMA connector. Solder a
pin to the side of the coax and file it diagonally to create a sharp point.
To increase the loading impedance we used an SMA "collar" that had been
filed out to place a series chip resistor of 470 ohms in series with the
c
Uh, isn't the national language of Argentina Spanish? Not Portuguese.
The web sites may still not be helpful, but at least aren't they in Spanish?
- Robert -
-Original Message-
From: George Sparacino
To: emc-p...@ieee.org
Date: Friday, Septem
Does anyone know labs set up to measure mobile phone ancillary equipment?
located in northern California area? Specifically Silicon Valley, San Jose
area.
Just need to test for radiated susceptibility at 3 V/m of a hands free
headset equipment when attached to a cell phone.
Yes, any chamber can
Guessing the best place to look would be in the "electronic detonator"
requirements. They must have some really stringent compliance requirements
to prevent mishaps.
- Robert -
-Original Message-
From: pgodf...@icomply.com
To: emc-p...@majordomo.ieee.org
List-Post:
Ron,
Interferernece? You need to find out about the specs for others then.
That frequency band is allocated for microwave ovens, which obviously have
lots of power.
Watch out in a metropolitan area around lunch time when all the restaruant
and office microwaves start operating, you'll see lots
The subject of short life of light bulbs appears often on the
alt.home.repairnewsgroup.
People come up with potential sources of problems like "on the same branch
with the sump pump(or well pump)", and "long lines to the light bulb".
Their solutions were to put in those dimmer switches that c
Many things to cover:
Mechanism for approval process over a distributed area.
Coordination of notification over a distributed area.
Is this a true ECN, or do you still need approvals? If you need approvals,
you might end up getting a change to your "ECN" Therefore, you'll need to
split the pro
Just my two cents worth with regard to temperature:
It is my understanding that for every 10C rise the life of the part is half
what it would have been.
- Robert -
Robert A. Macy, PEm...@california.com
408 286 3985 fx 408 297 9121
Not sure where to look.
But it is my understanding that the frequency of an impulse stimuli can
"lock" a person's alpha brain wave inducing trance-like states. Guess at
around the 5Hz to 10Hz range.
In particularly susceptible people, certain pulsating frequencies can induce
epileptic seizures.
I've got a copy of DimStrip which calculates their characteristics. Either
electrical properties from dimensions, or dimensions from required
electrical characteristics for stripline, or microstrip.
Runs under DOS and also has adjacent line capability.
Is there a place I can post it so people c
As long as language is an art form, having all of its nuances explored,
being legitimized by its users; it is highly unlikely that anyone will
successfully create a viable alternative.
- Robert -
-Original Message-
From: Muriel Bittencourt de L
Of interest, so I forward this to the group:
- Robert -
Robert A. Macy, PEm...@california.com
408 286 3985 fx 408 297 9121
AJM International Electronics Consultants
619 North First St, San Jose, CA 95112
-Original Message--
Ditto,
robertm...@aol.com
-Original Message-
From: Davis, Mike
To: 'cdup...@cs.com' ; rl...@tectrol.com
; emc-p...@ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Monday, March 13, 2000 8:38 AM
Subject: RE: EMC and product safety split?
>
>I concur with the comments from K. Ric
Derek,
The horn antenna is an impedance matching device for getting between 50 ohm
lines and 377 ohm free space while launching TEM mode wave fronts.
You could use the commercially available one which has an awful antenna
factor. It's broadband as a result of the ribs placed in the horn.
Just
Keith,
Without looking at the specifics. Disruption from a discharge can be caused
by direct high voltage gradients, localized breakdown which then applies
direct high voltage, and the often forgotten current injection where the
discharge makes enough current flow that the flow induces a voltage
Wouldn't BABT have such a facility, too?
- Robert -
-Original Message-
From: Jim Bacher
To: emc-p...@ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thursday, March 02, 2000 3:51 PM
Subject: Fwd:Re: UL 891
>
>forwarded for Chris Dupres.. Jim
>
>
>__
Jose,
I've seen software go by on
sci.engr.electrical.compliance
newsgroup.
I think more depth is discussed here than there, though.
You might take a look at Douglas Smith's web site
www.dsmith.org
Or Charles Grasso's web site:
http://www.ewh.ieee.
ation in measurements in this range than one would
otherwise expect, especially if the peak is just starting near 30MHz.
-----Original Message-
From: Gert Gremmen
To: Robert Macy ; Muriel Bittencourt de Liz
; Lista de EMC da IEEE
List-Post: emc-pstc@listserv.ieee.org
Date: Wednesday, February 2
Gert,
The connection (Wire A) the ground connection from the EUT to the ground
plane is indeed quite long and inductive and "does not exist" However, the
three wires HOT, Neutral, and GND form a 3 winding transformer which has a
core impedance in the range of 7uH for a six foot length of Belden
Muriel,
Without a ground plane you will not have the necessary "parasitic"
capacitance to the body of your EUT. It is this third path that often
causes failures up passed 1 MHz.
Definitely if you do your test in a "proper" setup versus a chamber you will
see differences in the 20MHz to 30MHz ra
Do SDL modems need to meet all the part 68 specs? Or can they violate just
a little (and where) and obtain a waiver, but still be certified?
- Robert -
-
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ot;Quiet Room" specs to
be used for mapping electrical brain activity. And those specs are going to
make a chamber look like a sieve.
-Original Message-
From: Robert Tims (EMX)
To: 'Robert Macy'
List-Post: emc-pstc@listserv.ieee.org
Date: Tuesday, January 25, 2000 9:40 AM
S
Don't need SQUIDs to read earth's field. Fluxgates have enough accuracy.
And the earth's natural noise floor is well above the SQUID so you don't
need to pay for all that extra. Remember, SQUIDs can observe the current
flow as metal rusts.
Check out Geometrics. They use the decay of the electro
Are fields stronger there?
The geologic survey people should have those numbers.
In California the fields are about 50microT which is pretty insignificant.
If you took a loop of wire that was 1 sq meter area and "flopped" it over in
the earth's field you'd have to do it within half a second even
At first that looked like what is asked for is the ability to pass signals
with a bandwidth of 10Hz. Given what they're looking for, stating frequency
would make it easier to understand.
But isn't the risetime 1/2pi F??
Or, are they just saying that the readings pop out at least 10 times per
se
radiators.
- Robert -
-Original Message-
From: cetest
To: Robert Macy ; rehel...@mmm.com ;
emc-p...@majordomo.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Monday, January 24, 2000 12:34 PM
Subject: RE: EMC Circuit Board Design
>Very good contribution R
Here are a set of rules worth recommending:
Engineering design checks:
1 Avoid "spaghetti logic" block diagram. Make certain there's a good flow
of functionality across and around the PCB. This includes using the concept
of transferring INFORMATION not ENERGY (except where one must, like with
Just my $.02 worth
It seems the problem is that willy-nilly use of lead in products leads to
the undesirable effect of lead migrating into the environment.
However, lead acid batteries are not banned, because there is strict
recycling.
Hmmm put those two together and the problem is solved.
Yes, we were applying the discharges too rapidly. Faster than 1 per 10
seconds did not allow adequate discharge. faster than 1 per 60 seconds
still did not allow adequate discharge.
So that's 10 minutes a discharge pointand still the test was not
adequate for the intent of the test.
True.
Same experience.
To "legitimize" the test we had to "discharge" the case/structure between
discharges.
Or, to really aggravate the test, we went from - to + to - to + which often
caused a failure.
But the point to test at all voltage levels is well made. The discharge
wavefront (and att
My opinion based upon working with 20KV, 200KV:
You need to have the outer shroud rated for 4KV also.
First, suppose the lamp doesn't strike? Then the 4KV is there a long time.
Second, insulation is a "tricky" thing. Its ability to hold off voltage
doesn't add, unless the materials are *very*
In my notes from university (when cps was prevalent) I see that originally
kcps was written and even mcps (handwriting was terrible hard to tell
whether the m was capital or not, the m for millivolts was always written
mV), then when the change to Hertz came about (that probably should be
hertz) a
Ken,
Rule of thumb which hopefully is accurate:
MOV's have a discrete lifetime (like 10 cycles at full rating) before
they're gone.
In order of joules absorbed versus package size:
Glass tubes, MOV's, silicon (from huskiest to weakest)
For turn on time:
silicon, MOV's, glass tubes (from fastes
David,
Measured 3 to 7 V/m around and inside a building that is within 200-300 feet
of the 10KW AM station's three towers. The towers are phased and the
amplitude you measure will change based upon time of day as the station
changes that phasing.
Amplitude is greatly affected by materials, meta
Heard of this high speed interface?
Anybody know about it?
Need information, please.
Something about IEEE1394
Is the cable defined *very* well? like CAT-5?
- Robert -
-
This message is coming from the emc-pstc discussion list.
To cancel your subscription, send
Generally, low frequency is dominated by differential mode caused by the
current demand of the switcher being imprinted across the impedances of the
components; then in the midrange its anybody's guess, but usually common
mode, because the capacitors and series impedance elements start to take
eff
There is a way to do this. *IF* you really want quantitative answers, you
can go through a laborious process (but kinda fun, too) of characterizing
each step of your system's block diagram and the impact you find along the
signal path.
You have to start "microscopic" then get to the "macroscopic
Well, in no particular order there's
Elliott Labs in Mtn View
Compliance Certification Services in Morgan Hill (possibly Sunnyvale, too)
I'm pretty sure that these can do it too:
Intertek in Redwood City
Electronic Compliance Labs in Sunol (or is that Sunnyvale)
EMCE in Fremont
I'll ask our county supervisors (they occupy this building, too)
- Robert -
-Original Message-
From: Bailin Ma
To: 'Robert Macy' ; Edward Fitzgerald
List-Post: emc-pstc@listserv.ieee.org
Date: Wednesday, December 08, 1999 9:01 AM
Subject: RE: Cell Phone Ha
Also, filling liquid to very close to the top prevents the bottle from
storing as much energy.
- Robert -
Coca Cola used to lose glass bottles until they reduced the air at the top.
-Original Message-
From: Mark
To: emc-p...@ieee.org
List-Post: emc-pstc@listserv.ieee.o
You were then extremely lucky that pieces of the wire did not lacerate your
eye.
- Robert -
-Original Message-
From: Antonio Sarolic
To: emc-p...@majordomo.ieee.org ; Robert Macy
Cc: Antonio
List-Post: emc-pstc@listserv.ieee.org
Date: Monday, December 06, 1999 12
Isn't there a little wire basket that keeps the cork in? Once that's
removed, it's essentially an armed explosive device.
I've been at parties where people removed the wire retainers and left the
bottles sitting in the ice, supposedly to make it easier to have their corks
removed later. Our hos
Has anybody calculated the skin depth that 900MHz has in the human body?
Is it shallow enough to make it impossible to do anything at the depth the
tumors reportedly occur?
- Robert -
-Original Message-
From: Patrick, Al
To: 'Martin Green' ; Patrick, Al
;
Near our building near downtown San Jose, in what are called "the county
buildings", one county building wing had 15 cases of very rare form of brain
tumors. The incidence of a single case is very rare but to have so many in
one building and only in one wing of that building is statistically
incr
The timing of the article seems to coincide with tests done on a major
automotive maker's products. What better way to discount the negative
publicity this will cause than to discredit the source?
Just food for thought. Especially, as many claim the article was more
emotional than factual.
The tricky part is making sure that the conversion is the right direction.
1 A/m = 0.01 A/cm
If you have oersteds and want amperes per meter, multiply by 79.577
If you have amperes per meter and want oersteds, multiply by 0.01257
- Robert -
Is this article in *.pdf format for any to pick up?
- Robert -
-Original Message-
From: John Juhasz
To: emc-p...@majordomo.ieee.org ;
'ri...@ieee.org'
Date: Thursday, November 18, 1999 12:09 PM
Subject: Floating Circuits - Protection Against Electric Shock
Good question.
Have you posted tosci.electronics.cad group to see what their
answers were?
- Robert -
-Original Message-
From: Rains,Mike
To: 'emc-p...@ieee.org'
List-Post: emc-pstc@listserv.ieee.org
Date: Wednesday, November 17, 1999 2:07 PM
Subject:
BE CAREFUL ! ! ! If this PS does not have Power Factor Correction
Many switching power supplies comply with the conducted emissions limits
BECAUSE of the conducting angle of the AC diodes.
Simply said, the AC rectifying diodes only come on for 15--18% of the duty
cycle. therefore the noise de
Don't know about a formal spec for this one, but the general "rule of thumb"
for low frequency conducted is less than 1% of the regulated value. For
example, less than 5mV peak to peak from the 5 Vdc, less than 12mVpp from
the 12Vdc, etc. Typically, the supplies put out half those values.
If yo
re can one do, but install it oneself?)
- Robert -
-Original Message-
From: Matthew Meehan
To: Robert Macy ; emc-p...@ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Tuesday, November 16, 1999 10:49 PM
Subject: Re: Grounding Questions
>Robert,
>I don&
Great, now all you need are some holes poked in the chamber.
- Robert -
-Original Message-
From: Price, Ed
To: 'emc-p...@ieee.org'
List-Post: emc-pstc@listserv.ieee.org
Date: Tuesday, November 16, 1999 7:36 PM
Subject: Shielded Enclosure Fire Hazard
>
>Hi Listmembers!
>
>
s in advance.
>
>Bob Martin, PE, NCE
>
>Sr. Technical Manager
>Intertek Testing Services
>(978)263-2662
>fax(978)263-7086
>r...@itsqs.com
>
>The opinions expressed are my own and not necessarily those of my
>employer.
>
>
>-Original Message-
>From
Why has no one mentioned using a GFI detector as a "failsafe" way to make
certain the installation is done per spec?
After all, in the US the manufacturer still comes out liable for any
damages.
- Robert -
-Original Message-
From: Crabb, John
To: '
For our building we used a 1500W glowing (resistive impedance load) heater.
Measure before, then turn on measure after and calculate the impedance.
Also measure adjacent branches to get a feel for how much impedance was in
the branch and how much was at the transformer and drop.
This is more accu
Hi, Hans,
Are you thinking of Four Phase ??
Weren't they a competitor to Tandem Computers?
Don't know who did the first "hot swap" disk drives. Patent search tell
you? Remember at one time it was really important to be able to pull out a
hard drive and secure it away in a safe someplace. Boy
Take a look at Radio Technical Commission for Aeronautics (RTCA) Document
No. DO-160B, "Environmental Conditions and Test Procedures for Airborne
Equipment"
The copy I have is dated July 20, 1984 Wow time flies!
The cover page is ISO 7137 if that's any help.
Basically, RTCA/DO-160 is ab
A small pedantic point here:
Coatings are usually rated in "ohms per square" which is dimensionless.
Looking at the resistance formula:
R = rho * length / Area = rho * length / ( width * thickness )
Given fixed rho and fixed thickness (of the coating) you can see that you're
left
Insertion loss measured in a 50 ohm system could give you misleading
performance expectations in your real world applications.
For example, free space impedance is 377 ohms, knowing the impedance of the
bead will tell you how much attenuation to expect.Or, many sources, like
those from the PC
>>Anaconda Sealtite is 12.6mm I/D, 17.8mm O/D;
Mark, thanks for the details, but are you certain about that 17.8mm diam?
Seems like that would really interfere with most holes.
- Robert -
-Original Message-
From: Mark
To: emc-p...@ieee.org
List-Post: emc-pstc@list
First, look at voltages induced by the magnetic fields:
The magnetic field from a single infinite long cable is:
u * I whereu = 4pi10-7
B = S is in meters
2 * pi * S
I know you don't have
Thanks for the details.
Just in case you "accidentally" permanently affect your monitor ( like I did
after playing with one of those really strong space magnets); use a cheap
electric pencil sharpener to degauss your screen's metal mask when the
power-on degausser isn't strong enough.
You're rig
I've got some toroids sitting on the bench (about 2 inches in diameter) that
would accomodate that with around 20 turns of doubled up 12 Awg wire.
You need them?
- Robert -
-Original Message-
From: Derek Walton
To: emc-p...@ieee.
Light colored, self adhesive shelf liner?
- Robert -
-Original Message-
From: WOODS, RICHARD
To: 'emc-p...@ieee.org'
List-Post: emc-pstc@listserv.ieee.org
Date: Friday, October 01, 1999 3:44 PM
Subject: RE: Coatings for Ferrite Tiles?
>
>We have been consi
Deflect 2 degrees?
Hmmm. The earth's magnetic field is around 50uT. To deflect the compass 2
degrees would take 1.7uT at a right angle, right? Therefore, you could set
a level of 1 uT "residual" magnetism for your testing requirement and have
some margin.
With that quantized number, you could
That pretty much takes a four point measurement.
However, if you're after only reading "about" the right value, or side by
side comparisons of the esr of a cap, try Dick Smith's esr meter.
Less than $60 in kit form from Australia. Is easy to put together and
extremely functional for measuring t
You can use the HP 141T (storage scope mainframe) and the analyzer plugins:
The 8552 IF section, 8553 (low frequency analyzer), 8554 (up to 1GHz),
and/or 8555 (way up there)
Some of these systems have been floating around for less than $1500, can't
get much cheaper if you want "qantitative" data.
Hmm... 5 mA 3000V that's a small 15 Watts.
Ethernet coax uses a high voltage cap in parallel with multiple resistors.
- Robert -
-Original Message-
From: Jim Eichner
To: 'EMC-PSTC - forum'
Cc: Tom Unger
List-Post: emc-pstc@listserv.ieee.org
Date:
sound card (also have a Turtle Beach Fiji with
>better S/N ratio) to generate a sweep and track/display the response.
>The
>only down-side to this is that you need to pad the output and input
>ports
>with 50 ohms (to duplicate the way OTHER filters are almost always
>tested
I use that HP Network analyzer that goes to 500MHz. On a component by
component basis. Then shove that all into a PSpice circuit which allows me
to add parasitics, etc.
Then I can play games with waveforms, risetimes, components, etc and pretty
much predict what the filter will do.
Sometimes a
My experience with the HP spectrum anaylyzers is that it has about 35dB NF.
You can calculate this from observation *and* from their data sheets.
So if you want the analyzer to not contribute, you need a lot of gain in
front. I'd recommend two stage amplifiers.
Plus, you really have to make cer
Not sure, but check into Light Rail. They use 600Vac (I believe) and use
the natural insulating qualities of concrete (where the rails are placed) to
give fairly good isolation from ground.
>From memory - the rails are the return terminal.
- Robert -
-
>
>Hello
Try Digital Power Corp in Fremont, CA
510 657 2635 or their VP Mktg: bh...@digipwr.com
- Robert -
>
>We are looking for a supplier of 300 Watt PS2, PC power supplies that have
PFC
>(Power Correction Factor).
>Here is the spec:
>
>It mus
Have you checked the resonance size of your ground plane? Or, multiple
resonance size?
Perhaps, the area where the turntable sits just aggravates all this.
- Robert -
On Thu, 29 Jul 1999, WOODS, RICHARD wrote:
>
> Thanks for all the comments. Some ha
Wow. Load the City Council meeting with as many people as you can get.
Even if they're only mildly interested in the issue. Have them look like
all the people are of like mind.
Unfortunately, the parallel here is like a person with a very nice view of
the ocean (beach valley river etc) and has
Absolutely, *PLUS* you pick up the advantage of natural shielding (the
ground plane) between you and the R&D going on down below.
- Robert -
On Mon, 3 May 1999, Gary McInturff wrote:
> I'll agree with Brent, and others, the headaches of a metal room or the
t two different sides of the same elephant?
>
> Ed
>
>
>
> From: Jeff Chambers
> Subject: Re: Harmonics
> Date: Fri, 23 Apr 1999 19:41:52 +0100
> To: Gary McInturff , "'ed.pr...@cubic.com'"
> , Robert Macy , Scott Do
s non-repeating
> signal. In Robert Macy example of a 25% duty cycle perfect square wave not
> containing a fourth harmonic is just a twice the fundamental square wave. If
> you apply the Fourier series math are a Fast Fourier Transform, FFT, on his
> illustration, the fundamental frequ
OOPS!
On Wed, 21 Apr 1999, Robert Macy wrote:
> Can't make a general statement. A "perfect" square wave of 50% duty
> cycle is missing all the even harmonics. A "perfect" 25% duty cycle is
> missing every harmonic that's a m
>The amount of harmonic content in a waveform is weather it is an even or
odd or somewhere in between function. A triangle waveform has all
harmonics decreasing in a 1/N function. A square waveform has harmonics
decreasing in a 1/(N*N) function. A perfect square wave (centered around
zero value
>The question is numbering of harmonics.
>One side says that given a fundamental frequency of 200 MHz, the first
harmonic is 400 MHz, the second harmonic is 600 MHz and the third harmonic
is 800 MHz.
>The other side says that given a fundamental frequency of 200 MHz, the
first harmonic is 200 MHz
Anybody know what it takes to use a 15 year old chamber and whip it into
shape for maximum certification capability (3 m range only)?
We're talking modular chamber with glued on cones to be dismantled and
reassembled (no doubt all the old cones will be lost)
Has anyone done this?
>I am trying to determine the maximum noise figure that I can have for my
1-16.5 GHz EMC receiver system which includes the horn, mixer for above 18
GHz, preamp, cable and spectrum analyzer. I know the following:
* Signal level received by the horn
* Gain through the system
* No
Anybody out there have a chamber for sale?
Need at least 3m testing of a small refrigerator size.
- Robert -
-
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IMHO the magnetic fields go right through the watch case and either
disrupt what's going on or can even magnetize the parts. Either way, the
parts are like "stuck" together and the watch won't run well.
Also, my father could never wear a watch, a great gift watch always would
stop. The same watch
Two issues of emc will hit you.
1) the trigger for the arc
This one is a pulse that is used to "fire" the arc. Usually, 20-30KV spikes
that hit once a second until an arc generation is detected.
The noise from these can be quite impressive, but at least they're not that
broadband.
2) the stan
If you have time, you can make the turntable (assuming light load) from a
drain pipe pvc (large diameter) which is attached to an antenna rotor
(those used in people's homes who live in fringe area).
The thing was all strapped and glued which had to be inexpensive.
Although uncalibrated position
I've got copies of the MPRII rules. They'd have to be out of date by now,
(circa 1990) but at least it's good reading. I should have the origin of
the MPRII printouts somewhere, but not off the top of my head.
If you strike out, give me a call:
Robert Macy
What is equivalent to :
a 4 inch long wire excited at one end with 3 Vpp at 100MHz
a 4 inch long slot with swirling current of how much
to be equivalent radiators?
- Robert -
PS My guess was 10-100mA, but I would like to get a true qualitative
answer.
The ferrites "remove" the cable from the fields to some degree. No matter
how perfect the baluns are the cable still represents a conductor out in
the middle fo the fields you're working with.
- Robert -
On Thu, 12 Nov 1998, WOODS, RICHARD wrote:
> Hans,
If this temperature is the absolute value, not much of a problem. But if
this is the "rise above ambient", big problem.
That means you get about 24C rise and if that's operated in a hot office
space like at 35C then thee base plate gets *very* hot.
Once in our non-airconditioned office on a
Sorry, to not get this in before your summary.
When Sony (video div) was my client, they had an internal spec margin
requirement of 8 dB.
That's right! 8 dB below Class B limits.
After going though that I'm convinced to use Sony equipment as support
electronics.
It is my understanding that this margin is a carryover from VDE
requirements where for statistical reasons you need 2.2 (?) dB margin in
order to infer that from a single unit test, your other units will also
comply. It is also my understanding that that margin was waived when 3-8
units were test
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