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Hi All,

I have been looking around the net for basic written document with illustrations on the handling, use and cleaning of coaxial RF N-type and SMA connectors for everyday use?

Has someone like HP ever written such a document?

Thank you in advance.

Regards

Gerald
VK3GJM

On Tue, Dec 18, 2012 at 11:21 PM, johncharlesgord <johngord@... <mailto:johngord%40verizon.net>>wrote:

**


Jeff,

You can still make the idea work by using multiple resistors of the same
value. You can make a 10:1 divider by using, say, 10 each 10K resistors;
all can be checked on the same resistance scale. You need to correct for
any loading by the meter input, of course, but the input impedance

of the

3478A is very high on the 3V and lower DC ranges.

Another way of doing a 10:1 divider:



You need to match three equal value resistors and a trimpot is used for
fine tuning by measuring two equal voltages so you would always be on the
same range of the meter you are using for tuning.

Orin.

Thanks. I didn't use an attenuator. I just set the oscilloscope on 50-ohm
input impedance and connected the function generator directly to it. I
couldn't figure out why they called for an attenuator, to be honest...

-Matthew

--- In hp_agilent_equipment@..., "J. Forster" <jfor@...>
wrote:

Are you terminating the attenuator? Most attenuators are designed to
operate with a 50 Ohm source and load.

-John

==============

Thanks for the response. I thought of the same thing so I tried three
different oscilloscopes:

1) Tektronix 2465 - 300MHz
2) Tektronix TDS3034B - 300MHz
3) HP 54502A - 400MHz

All produced roughly the same results. I even tried turning on the

150MHz

bandwidth limit on the TDS to see if it made any difference but it

didn't,

implying that there are not harmonics that high.

-Matthew


--- In hp_agilent_equipment@..., "Dave B" <dave@> wrote:

On 19 Dec 2012 at 13:52, hp_agilent_equipment@... wrote:

______________________________________________________________________
7. Triangle Wave Flatness HP 8116A
Posted by: "medasaro" medasaro@ medasaro
Date: Tue Dec 18, 2012 11:10 pm ((PST))

All -
I am trying to calibrate one of these generators and I can't

seem

to make it past step 29 in the calibration procedure. The
procedure reads:

Flatness
23. Set the HP 8116A frequency to 2.99 MHz.
24. Connect the HP 8116A's main output to the oscilloscope via a
6 dB attenuator and set the channel attenuation-factor to 2.
25. Connect the HP 8116A's trigger output to the oscilloscope's
trigger input via a 20 dB attenuator.
26. Set the oscilloscope to 160 mV/div and 100 ns/div.
27. Record the ampltude of the output signal.
28. Set the HP 8116A frequency to 9.99 MHz.
29. Check that the output amplitude has decreased by between 2%
and 4% of the amplitude at 2.99 MHz. If not, you must change
the values of both A1R220 and A1R223 (both must have the
same value). Refer to Table 9-1.


However, my amplitude decreases by more then 5%. I have tried three
different slope ICs (out of various generators I have) and some
produced better flatness then others, but none met spec. I also

tried

the same procedure on a different generator (also in need of
calibration) and it too failed, but not as badly. I have tried the
test on two oscilloscopes with the same results. Finally, I tried
increasing the value of R220 and R223, but that, too, didn't seem

to

help, at least not enough. Any other ideas?

As a final note, at these high-frequencies the triangle wave gets
rounded-off at the peaks. I have been measuring the amplitude to

the

actual peak of the waveform, not where the triangle wave would peak

if

it was not rounded. I assume this is correct...

Thanks in advance!
Matthew

Hi.

Cant' help but wonder, what 'scope are you using, and has it enough
realtime bandwidth to not distort (filter some harmonic content of)

the

Triangle wave, so that it begins to aproximate a sine shape.

You're (at a guess) going to need a truly flat response on your

'scope

out way past 50 or more MHz I suspect.

Just musing.

Dave B.

Are you terminating the attenuator? Most attenuators are designed to
operate with a 50 Ohm source and load.

-John

==============

Thanks for the response. I thought of the same thing so I tried three
different oscilloscopes:

1) Tektronix 2465 - 300MHz
2) Tektronix TDS3034B - 300MHz
3) HP 54502A - 400MHz

All produced roughly the same results. I even tried turning on the 150MHz
bandwidth limit on the TDS to see if it made any difference but it didn't,
implying that there are not harmonics that high.

-Matthew


--- In hp_agilent_equipment@..., "Dave B" <dave@> wrote:

On 19 Dec 2012 at 13:52, hp_agilent_equipment@... wrote:

______________________________________________________________________
7. Triangle Wave Flatness HP 8116A
Posted by: "medasaro" medasaro@ medasaro
Date: Tue Dec 18, 2012 11:10 pm ((PST))

All -
I am trying to calibrate one of these generators and I can't seem
to make it past step 29 in the calibration procedure. The
procedure reads:

Flatness
23. Set the HP 8116A frequency to 2.99 MHz.
24. Connect the HP 8116A's main output to the oscilloscope via a
6 dB attenuator and set the channel attenuation-factor to 2.
25. Connect the HP 8116A's trigger output to the oscilloscope's
trigger input via a 20 dB attenuator.
26. Set the oscilloscope to 160 mV/div and 100 ns/div.
27. Record the ampltude of the output signal.
28. Set the HP 8116A frequency to 9.99 MHz.
29. Check that the output amplitude has decreased by between 2%
and 4% of the amplitude at 2.99 MHz. If not, you must change
the values of both A1R220 and A1R223 (both must have the
same value). Refer to Table 9-1.


However, my amplitude decreases by more then 5%. I have tried three
different slope ICs (out of various generators I have) and some
produced better flatness then others, but none met spec. I also tried
the same procedure on a different generator (also in need of
calibration) and it too failed, but not as badly. I have tried the
test on two oscilloscopes with the same results. Finally, I tried
increasing the value of R220 and R223, but that, too, didn't seem to
help, at least not enough. Any other ideas?

As a final note, at these high-frequencies the triangle wave gets
rounded-off at the peaks. I have been measuring the amplitude to the
actual peak of the waveform, not where the triangle wave would peak if
it was not rounded. I assume this is correct...

Thanks in advance!
Matthew

Hi.

Cant' help but wonder, what 'scope are you using, and has it enough
realtime bandwidth to not distort (filter some harmonic content of) the
Triangle wave, so that it begins to aproximate a sine shape.

You're (at a guess) going to need a truly flat response on your 'scope
out way past 50 or more MHz I suspect.

Just musing.

Dave B.

Thanks for the response. I thought of the same thing so I tried three
different oscilloscopes:

1) Tektronix 2465 - 300MHz
2) Tektronix TDS3034B - 300MHz
3) HP 54502A - 400MHz

All produced roughly the same results. I even tried turning on the 150MHz
bandwidth limit on the TDS to see if it made any difference but it didn't,
implying that there are not harmonics that high.

-Matthew


--- In hp_agilent_equipment@..., "Dave B" <dave@...> wrote:

On 19 Dec 2012 at 13:52, hp_agilent_equipment@... wrote:

______________________________________________________________________
7. Triangle Wave Flatness HP 8116A
Posted by: "medasaro" medasaro@... medasaro
Date: Tue Dec 18, 2012 11:10 pm ((PST))

All -
I am trying to calibrate one of these generators and I can't seem
to make it past step 29 in the calibration procedure. The
procedure reads:

Flatness
23. Set the HP 8116A frequency to 2.99 MHz.
24. Connect the HP 8116A's main output to the oscilloscope via a
6 dB attenuator and set the channel attenuation-factor to 2.
25. Connect the HP 8116A's trigger output to the oscilloscope's
trigger input via a 20 dB attenuator.
26. Set the oscilloscope to 160 mV/div and 100 ns/div.
27. Record the ampltude of the output signal.
28. Set the HP 8116A frequency to 9.99 MHz.
29. Check that the output amplitude has decreased by between 2%
and 4% of the amplitude at 2.99 MHz. If not, you must change
the values of both A1R220 and A1R223 (both must have the
same value). Refer to Table 9-1.


However, my amplitude decreases by more then 5%. I have tried three
different slope ICs (out of various generators I have) and some
produced better flatness then others, but none met spec. I also tried
the same procedure on a different generator (also in need of
calibration) and it too failed, but not as badly. I have tried the
test on two oscilloscopes with the same results. Finally, I tried
increasing the value of R220 and R223, but that, too, didn't seem to
help, at least not enough. Any other ideas?

As a final note, at these high-frequencies the triangle wave gets
rounded-off at the peaks. I have been measuring the amplitude to the
actual peak of the waveform, not where the triangle wave would peak if
it was not rounded. I assume this is correct...

Thanks in advance!
Matthew

Hi.

Cant' help but wonder, what 'scope are you using, and has it enough
realtime bandwidth to not distort (filter some harmonic content of) the
Triangle wave, so that it begins to aproximate a sine shape.

You're (at a guess) going to need a truly flat response on your 'scope
out way past 50 or more MHz I suspect.

Just musing.

Dave B.

On 19 Dec 2012 at 13:52, hp_agilent_equipment@... wrote:

______________________________________________________________________
7. Triangle Wave Flatness HP 8116A
Posted by: "medasaro" medasaro@... medasaro
Date: Tue Dec 18, 2012 11:10 pm ((PST))

All -
I am trying to calibrate one of these generators and I can't seem
to make it past step 29 in the calibration procedure. The
procedure reads:

Flatness
23. Set the HP 8116A frequency to 2.99 MHz.
24. Connect the HP 8116A's main output to the oscilloscope via a
6 dB attenuator and set the channel attenuation-factor to 2.
25. Connect the HP 8116A's trigger output to the oscilloscope's
trigger input via a 20 dB attenuator.
26. Set the oscilloscope to 160 mV/div and 100 ns/div.
27. Record the ampltude of the output signal.
28. Set the HP 8116A frequency to 9.99 MHz.
29. Check that the output amplitude has decreased by between 2%
and 4% of the amplitude at 2.99 MHz. If not, you must change
the values of both A1R220 and A1R223 (both must have the
same value). Refer to Table 9-1.


However, my amplitude decreases by more then 5%. I have tried three
different slope ICs (out of various generators I have) and some
produced better flatness then others, but none met spec. I also tried
the same procedure on a different generator (also in need of
calibration) and it too failed, but not as badly. I have tried the
test on two oscilloscopes with the same results. Finally, I tried
increasing the value of R220 and R223, but that, too, didn't seem to
help, at least not enough. Any other ideas?

As a final note, at these high-frequencies the triangle wave gets
rounded-off at the peaks. I have been measuring the amplitude to the
actual peak of the waveform, not where the triangle wave would peak if
it was not rounded. I assume this is correct...

Thanks in advance!
Matthew

Hi.

Cant' help but wonder, what 'scope are you using, and has it enough
realtime bandwidth to not distort (filter some harmonic content of) the
Triangle wave, so that it begins to aproximate a sine shape.

You're (at a guess) going to need a truly flat response on your 'scope
out way past 50 or more MHz I suspect.

Just musing.

Dave B.

HP was not the only one who did this. I have seen at least two Tek 453
scopes
on e-bay with blue front panels for the Air Force. When I worked at
Philips
they would also custom color - at an additional cost.


On Wednesday, December 19, 2012 13:56:17 you wrote:

I won't say exactly who the company was, but that color was officially
named "Raytheon Blue" and was option A27. :-)

I agree, a complete waste of money.

--- In hp_agilent_equipment@..., "W2HX" <w2hx@...> wrote:

Check out the color.

not mine, no connection, action figures sold separately.


73 Eugene W2HX

--
Mike McGinn KD2CNU
Ex Uno Plurima
No electrons were harmed in sending this message, some were
inconvenienced.
** Registered Linux User 377849

I won't say exactly who the company was, but that color was officially
named "Raytheon Blue" and was option A27. :-)

I agree, a complete waste of money.

--- In hp_agilent_equipment@..., "W2HX" <w2hx@...> wrote:

Check out the color.

not mine, no connection, action figures sold separately.


73 Eugene W2HX

Check out the color.

not mine, no connection, action figures sold separately.


73 Eugene W2HX

John, awesome idea. So just build the higher resistance side of the divider with resistors that were all measured from the same range that the low side will be on. That's a great idea. The sum of that would then just plug in to the normal divider formulas to compute the other missing resistor. Once the computed value is known a resistor would be trimmed until the reading on the meter equals the value of the missing resistor. In the end you would have a divider with a ratio that has precision as good as the highest resolution of the meter you used to build it. The meter loading could be added to the formula during computation for the resistor the voltage reading will be taken from. I've made up an excel sheet that I can just plug in my precision reference voltage, the needed test voltage,the value of one resistor and the meter load. It then gives me the missing resistor value. A second part of the same sheet lets me plug in the values I'm getting to see how far off in percentage it'll be.

I think this idea would work really well for what it is. I suspect with a little patience 0.01% could be achieved. Beyond that would require a higher resolution meter and a lot more time. Perhaps with a 6 1/2 digit meter 0.001% could be done. At the very least it's a nice sanity check exercise. Of course any results are only as good as the precision of the reference used. I think for my needs getting even 0.01% would be just fine. It would be better then most of what I would buy brand new in the price range of the used gear.

Thanks,

Jeff

On 12/19/2012 12:21 AM, johncharlesgord wrote:

Jeff,

You can still make the idea work by using multiple resistors of the same value. You can make a 10:1 divider by using, say, 10 each 10K resistors; all can be checked on the same resistance scale. You need to correct for any loading by the meter input, of course, but the input impedance of the 3478A is very high on the 3V and lower DC ranges.

--John Gord

--- In hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com>, Jeff Machesky <jeff@...> wrote:

Found the hole in my own idea so I thought I would post it just in case
someone attempts it.

The problem is the "uncalibrated" meter is going to have different
amounts of error in different resistance ranges. So measuring the
divider resistors will result in an error percentage not less then the
differential between two ranges used to measure the resistors. That's
not to say a calibrated meter wouldn't work to create the references

but

at that point you may as well just measure the voltages. Ohhh well.
Sorry for the wasted posts.

Jeff

On 12/18/2012 8:14 PM, Jeff Machesky wrote:

Just some food for thought and criticism. Let's say all you can get is
a 2.5 or 5.0 volt precision reference. You could in theory use the
high resolution of your 5 1/2 or 6 1/2 + digit meter to trim resistors
to get precision divider ratios. Even if your meter was not in cal the
ratio would still be accurate. So for each calibration range you could
divide down your reference or source as needed to match your precision
reference. I think this method would get most of us well in the
ballpark. It would require a whole lot of patience however and I'm
sure would become less accurate at the higher voltages. Perhaps even
use a very low offset op-amp to buffer your readings. Once voltage is
accurate you could check resistance ranges with a small amount of
precision resistors and again trim the other half of a voltage divider
until your voltage equates to a value that matches your desired
resistance.

So one uncalibrated meter plus one high precision voltage

reference and

a bit of patience and a good calculator and you can get a fairly close
cal. Well in theory at least.

Any thoughts ?

Jeff

On 12/18/2012 8:54 AM, Chuck Harris wrote:

The 3478A is a nice meter, but bear in mind that it is 300V max.
It is accurate, stable, and works smoothly. It is easily controlled
over HPIB.

In its deficiency corner, is the 300V max,and a non back lit LCD

that

tends to get lost in the shadows.

I have never needed to calibrate mine, but I am pretty sure that you
need to complete the calibration of all steps before you leave a
particular function, say DCV, or ACV, or Ohms....

The calibration procedure takes a measurement of a known standard
on a particular range, and creates an offset that it used when it
calculates the voltage to display. The 30mv standard only calibrates
the offset for the 30mv range. The 3V standard, the 3V range...

You shouldn't have to pay more than about $100 for a working

calibrated

3478A. Tucker has them for sale periodically.

9 times out of 10, a voltage measured by a scope's trace is good

enough.

Did I mention that the 3478A only measures up to 300V?

-Chuck Harris

Jeff Machesky wrote:

So it's about the time of year where I'm allowed to buy one

piece of

test gear and I'm thinking I want a bench meter with higher
resolution. The best I've got so far is the Tek 2465BDM which

has a

20,000 count 0.03% accuracy DMM. It's however a little out of

cal and

I just don't want to spend the cash to get it back in perfect

spec.

It's also a bit crazy to have a scope running just to use the DMM.
This brings me to the 3478A. While I could technically afford

to buy a

new 120,000 count DMM I just can't justify the cost for the

hobby type

work that I do. Plus I love working with the older gear and saving

money.

Couple quick questions about the 3478A:

Can one range be calibrated at a time? This is not highly

clear in the

service manual. Can I calibrate just the 3V range for example?
Are they reliable, or will I have to fix up most of what I

would buy

on say ebay?

The problem I have with the meter on my Tek is that you have to

run the

entire cal for each measurement type, If you start with DC you

have to

go all the way up the range from millivolts up to several hundred
volts. As we all know it's easy to get a precision calibrated low
voltage references such as a DMM check board, it's another thing

to get

500 volts or higher reference at the spec of the meter.

So is this really a meter to buy if your willing to send it

off to be

calibrated or have a calibration transfer standard meter

that's above

the specs of the 3478A? In other words if all you have is just

a few

standards are you wasting your time?

Has anyone had any luck using a precision reference, some

precision

resistors and an op-amp to generate other reference voltages

with any

degree of accuracy? Also has anyone found a good source of say 500
volts 60 Hz AC? The right audio amp and a sig gen can get you

some of

the other odd cal standards. High voltage DC is just so much

easier to

obtain then a nice high voltage sine wave.

Sorry for the random questions, and thanks for any replies. The
54111D is still running great. My thanks again for everyone

who helped

me fix the ROM's.

Jeff



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Aha! The proper colour for test equipment (says he, ducking, weaving and
running for cover).

D.
-----Original Message-----
From: hp_agilent_equipment@...
[mailto:hp_agilent_equipment@...] On Behalf Of W2HX
Sent: 19 December 2012 05:08
To: hp_agilent_equipment@...
Subject: [hp_agilent_equipment] neat color for an 8566!

Check out the color.

not mine, no connection, action figures sold separately.


73 Eugene W2HX





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