I downloaded the Service Support Software package so I may
try my hand at checking out my somewhat new 8648C Sig Gen.
Upon opening the SW package up pops a window asking for a
name and password. No matter what I enter it says NG ??
Is there a magic name and PW to get into the files ?
Thanks for your help,
73, Dick, W1KSZ
ps: I am using it on a WIN 7 machine.
|
Re: Application Note 122: EMI Measurement Procedure
Sean,
If you are interested in the reference to MIL-STD-826A as referenced in the HP Memory Project page AN index, try
?
Greg
|
Re: 5335A keyboard LED interesting thing
Ha! Wouldn't be the first time a hardware engineer didn't trust the software engineer(s) not to f-up! Been there, done that! Said the hardcore hardware guy who can't resist a potshot at the software weenies!
Jim Ford
toggle quoted message
Show quoted text
------ Original Message ------ From: "Szabolcs Szigeti" <szigiszabolcs@...> To: [email protected]Sent: 4/14/2020 7:05:36 AM Subject: [HP-Agilent-Keysight-equipment] 5335A keyboard LED interesting thing Hi,
Sorry if it is know, but it is new to me. While fixing the LED in one
of the keys of my 5335A, I have stumbled upon some interesting thing.
All keys have LEDs in them, even those where the keycap does not have
the transparent insert. So far this is not unusual, as manufacturing
could probably be simpler if one has to deal with only one type of
keys, although I found no particular reason why the actual LED had to
be populated as it is not part of the key mechanism. I was able to
replace it with some fiddling and without removing the switch.
However, what I found is that the Gate Cycle Norm key is supposed to
have no light, but the LED there is actually controlled by the CPU and
it lights up if pressed. I saw it light up when the keyboard was
removed from the instrument front panel for testing and then tried it
with the cap removed to verify.
So likely at the late stages of development sometime, someone decided
that this button should not light, and it was accomplished by
replacing the keycap but not modifying the firmware.
I find this quite amusing.
Szabolcs
|
Re: hp8350b/hp83595a front panel mod
? I¡¯ve got a few of those original cable assemblies.? If someone needs one contact me offline. ? Tom ?
|
Re: hp8350b/hp83595a front panel mod
Good thing you put in the lower torque spec for 3.5 mm to SMA connection, Steve.? I was about to recommend that the stainless steel SMA connectors be torqued to 8 in-lbs or 0.9 N-m (not N/m).? I read somewhere that brass SMAs should be torqued to 5 in-lbs (0.57 N-m) and stainless steel SMAs should be torqued to 8 in-lbs (0.9 N-m), as determined by the male connector.? I suppose you don't want to overtorque an SMA male mating with a 3.5 mm female to avoid overpenetration and damage to the female (sounds painful!).? I understand a connector gauge is in order here because of the poor control over center pin protrusion in SMA males and the fragility of 3.5 mm and 2.92 mm (K connectors) female coaxial connectors.
Thanks.
Jim Ford
------ Original Message ------
Sent: 4/14/2020 6:18:49 AM
Subject: Re: [HP-Agilent-Keysight-equipment] hp8350b/hp83595a front panel mod
Hi Jan,
The semi-rigid is standard .141 with precision stainless steel
SMA connectors. It is L-shaped with a bit of an offset in the leg
that goes to the front panel connector:
Please note that the front panel connector is not just a
feedthrough, it has a DC block built into it. If you substitute a
straight bulkhead connector you lose that DC protection. I would
recommend removing the rear panel connector and using it instead.
You can always revert to rear panel output if you need to. There's
precious little room in the plug in to add a relay to allow
switching back and forth. If you use your 3.5mm bulkhead connector
I'd recommend a connector saver and an external DC block. Better
yet go to an SMA bulkhead connector instead of the 3.5mm as I'd
bet you'll be using SMA for everything else as 3.5mm connectors
are expensive and fragile.
Since you will be mating 3.5mm to SMA do be aware that those
connections should be torqued to 5 in/lb, .57 N/m, not the usual
SMA to SMA or 3.5 to 3.5 value of 8 in/lb, .9 N/m
If amplitude accuracy needs to be within specs you'll need to do
an RF amplitude calibration once everything is in place as you've
made changes to the RF output path.
Good luck with the project and let us know how it goes. I've
switched an 8340B from rear to front panel output but my 83595A's
came with front panel output so I've not needed to modify them.
Cheers,
Steve K.
WB?DBS
On 4/13/2020 11:27 AM, Jan de Jongh
wrote:
Hi all,
I'm trying to get my RF output on the front panel instead of at
the rear on an hp83595a (26.5 GHz), while leaving the rear-panel
option intact. I already have the front-panel connector from ebay
and need to make a semi-rigid with 3.5mm connectors to (I guess,
need to verify) the 55 dB attenuator.
Does anyone know what type of semi-rigid is used by HP in the
hp83595a for the RF output and/or has suggestions for sourcing the
connectors? (Sorry, complete semi-rigid noob here...) BTW, the
front-panel connector I have is an APC3.5 feed through.
Thanks,
Jan
|
Re: GPSDO connected to external ref inputs
<shameless plug>
The TAPR TADD-1
() is a
well-proven 6 channel RF distribution amp with low phase noise and good
output isolation. The input and output are transformer coupled and the
grounds can be isolated if desired. It's designed for just this sort of
application.
</shameless plug>
John
----
toggle quoted message
Show quoted text
On 4/13/20 4:51 PM, Jim Ford wrote: Thanks, Greg.
I will put the 5087A on my wishlist!? Nice that it allows individual
output amplitudes to be set (how, though?) and that it has a large
number of outputs.? Although I couldn't find a picture of the rear panel
on ebay; I expect a forest of BNC jacks.
Downside is the size; I have my?BG7TBL distribution amp suspended from
the bottom of my equipment shelf over my bench, so it takes up zero
bench or shelf space.? Right next to it is the GPSDO, also tucked under.
Mini-Circuits I'm quite familiar with, as the guy running the show
there, Ted Heil, and the local rep at Coastal RF Systems, Frank Edwards,
and I all worked together at Powerwave Technologies back in the late
1990's to early 2000's.? Yeah, I've been amazed for 30 or so years at
how their prices are so much more reasonable than anybody else's.
Nice collection you have!? Although I hate to use the term collection,
as it violates the "Love people and use things, not the other way
around" principle.? Collecting implies not using because it devalues the
items, and I've never understood why people would have say, HotWheels
cars they couldn't play with, or guitars nobody could play ("Don' even
look a' it!" to quote Nigel Tufnel in This Is Spinal Tap!).? OK, I'll
get off the soapbox now!
Jim
------ Original Message ------
From: "Greg Muir via groups.io" <big_sky_explorer@...
<mailto:big_sky_explorer@...>>
To: [email protected]
<mailto:[email protected]>
Sent: 4/13/2020 10:47:35 AM
Subject: Re: [HP-Agilent-Keysight-equipment] GPSDO connected to external
ref inputs
Jim,
?
I have a HP 5087A distribution amp feeding output from an older HP
Z3816 GPSDO to several pieces of equipment.? These include:
?
Agilent E4425B signal generator
Agilent 8714ET network analyzer
EIP 548A microwave frequency counter
HP 3575A gain/phase meter
HP 5335A counter
HP 8920A RF communication test set
HP 53310A modulation domain analyzer
HP K34-9991A phase comparator
PTS 250 frequency synthesizer
Tracor 527E frequency difference meter
Tracor 895A linear phase/time comparator
Wayne Kerr PSG2400L signal generator
?
Except for the Z3816/5087 units most of the driven equipment is in a
power-down state unless needed.? The port on the 527E is switchable to
an external connector on the bench for other test applications.? In
all, I feed one volt p-p or less to all of the equipment and it stays
happy.? The advantage with the 5087A is that each output is
individually adjustable to suit the needs of the attached hardware.
?
If any of your units cannot tolerate a 4V amplitude I suggest that you
pick up an in-line 50 ohm attenuator either from your favorite auction
site or from Mini-Circuits (no affiliation however I rely on them for
their low-cost high-quality products).? 4 volts does seem a little
excessive for most external reference inputs since I am assuming you
are referring to RMS amplitude and not peak-to-peak value
?
Greg
|
Re: GPSDO connected to external ref inputs
Thanks, Greg.
I will put the 5087A on my wishlist!? Nice that it allows individual output amplitudes to be set (how, though?) and that it has a large number of outputs.? Although I couldn't find a picture of the rear panel on ebay; I expect a forest of BNC jacks.
Downside is the size; I have my?BG7TBL distribution amp suspended from the bottom of my equipment shelf over my bench, so it takes up zero bench or shelf space.? Right next to it is the GPSDO, also tucked under.
Mini-Circuits I'm quite familiar with, as the guy running the show there, Ted Heil, and the local rep at Coastal RF Systems, Frank Edwards, and I all worked together at Powerwave Technologies back in the late 1990's to early 2000's.? Yeah, I've been amazed for 30 or so years at how their prices are so much more reasonable than anybody else's.
Nice collection you have!? Although I hate to use the term collection, as it violates the "Love people and use things, not the other way around" principle.? Collecting implies not using because it devalues the items, and I've never understood why people would have say, HotWheels cars they couldn't play with, or guitars nobody could play ("Don' even look a' it!" to quote Nigel Tufnel in This Is Spinal Tap!).? OK, I'll get off the soapbox now!
Jim
------ Original Message ------
Sent: 4/13/2020 10:47:35 AM
Subject: Re: [HP-Agilent-Keysight-equipment] GPSDO connected to external ref inputs
Jim,
?
I have a HP 5087A distribution amp feeding output from an older HP Z3816 GPSDO to several pieces of equipment.? These include:
?
Agilent E4425B signal generator
Agilent 8714ET network analyzer
EIP 548A microwave frequency counter
HP 3575A gain/phase meter
HP 5335A counter
HP 8920A RF communication test set
HP 53310A modulation domain analyzer
HP K34-9991A phase comparator
PTS 250 frequency synthesizer
Tracor 527E frequency difference meter
Tracor 895A linear phase/time comparator
Wayne Kerr PSG2400L signal generator
?
Except for the Z3816/5087 units most of the driven equipment is in a power-down state unless needed.? The port on the 527E is switchable to an external connector on the bench for other test applications.? In all, I feed one volt p-p or less to all of the equipment and it stays happy.? The advantage with the 5087A is that each output is individually adjustable to suit the needs of the attached hardware.
?
If any of your units cannot tolerate a 4V amplitude I suggest that you pick up an in-line 50 ohm attenuator either from your favorite auction site or from Mini-Circuits (no affiliation however I rely on them for their low-cost high-quality products).? 4 volts does seem a little excessive for most external reference inputs since I am assuming you are referring to RMS amplitude and not peak-to-peak value
?
Greg
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
Yeah, the PTS generators are really, really good for PN, particularly at
HF frequencies.
toggle quoted message
Show quoted text
On 4/14/20 11:38 AM, Mike Feher wrote: I agree. However, I do put the PTS stuff in a much higher category than
the 3325A. Thanks ¨C Mike
?
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115
?
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of John Ackermann N8UR
Sent: Tuesday, April 14, 2020 11:31 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 3325A Phase noise (and
reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
?
Trying to compare generators with all the variables that affect PN can
drive you crazy, but would be worthwhile.? I did tests on a bunch of PTS
synthesizers and one of them included a comparison of 10.000000 MHz vs.
9.999999 MHz:
?
?
73,
John
----
On 4/14/20 11:22 AM, Mike Feher wrote:
Very interesting John. Actually, I am surprised as to how good it is. Although, since the OCXO is also at 10 MHz, it would be more interesting to see it at some random frequency. Maybe as compared to an 8662A. 73 ¨C Mike -=-=-=-=-=-
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
I agree. However, I do put the PTS stuff in a much higher category than the 3325A. Thanks ¨C Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ?
toggle quoted message
Show quoted text
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of John Ackermann N8UR
Sent: Tuesday, April 14, 2020 11:31 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6 ? Trying to compare generators with all the variables that affect PN can drive you crazy, but would be worthwhile.? I did tests on a bunch of PTS synthesizers and one of them included a comparison of 10.000000 MHz vs. 9.999999 MHz: ? ? 73, John ---- On 4/14/20 11:22 AM, Mike Feher wrote: > Very interesting John. Actually, I am surprised as to how good it is. > Although, since the OCXO is also at 10 MHz, it would be more > interesting to see it at some random frequency. Maybe as compared to > an 8662A. 73 ¨C Mike -=-=-=-=-=-
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
Trying to compare generators with all the variables that affect PN can
drive you crazy, but would be worthwhile. I did tests on a bunch of PTS
synthesizers and one of them included a comparison of 10.000000 MHz vs.
9.999999 MHz:
73,
John
----
toggle quoted message
Show quoted text
On 4/14/20 11:22 AM, Mike Feher wrote: Very interesting John. Actually, I am surprised as to how good it is.
Although, since the OCXO is also at 10 MHz, it would be more interesting
to see it at some random frequency. Maybe as compared to an 8662A. 73 ¨C
Mike
?
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115
?
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of John Ackermann N8UR
Sent: Tuesday, April 14, 2020 11:10 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 3325A Phase noise (and
reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
?
Several years ago I did phase noise measurements on a 3325B.? The
results are here:
?
?
The unit had the standard (not high-stability) oscillator and my
measurements showed a dramatic PN improvement using a high-quality
external reference.
?
John
?
-=-=-=-=-=-
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
Very interesting John. Actually, I am surprised as to how good it is. Although, since the OCXO is also at 10 MHz, it would be more interesting to see it at some random frequency. Maybe as compared to an 8662A. 73 ¨C Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ?
toggle quoted message
Show quoted text
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of John Ackermann N8UR
Sent: Tuesday, April 14, 2020 11:10 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6 ? Several years ago I did phase noise measurements on a 3325B.? The results are here: ? ? The unit had the standard (not high-stability) oscillator and my measurements showed a dramatic PN improvement using a high-quality external reference. ? John ? -=-=-=-=-=-
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
On Tue, Apr 14, 2020 at 05:10 PM, John Ackermann N8UR wrote:
Several years ago I did phase noise measurements on a 3325B. The
results are here:
The unit had the standard (not high-stability) oscillator and my
measurements showed a dramatic PN improvement using a high-quality
external reference.
John
Hi John, Thanks for that, very enlightening! Raymond
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
I should qualify that -- dramatic improvement at low offsets. More than
about 10 Hz from the carrier, the results were the same with either
reference.
toggle quoted message
Show quoted text
On 4/14/20 11:10 AM, John Ackermann N8UR via groups.io wrote: Several years ago I did phase noise measurements on a 3325B. The
results are here:
The unit had the standard (not high-stability) oscillator and my
measurements showed a dramatic PN improvement using a high-quality
external reference.
John
On 4/14/20 8:50 AM, Raymond Domp Frank wrote:
Hi Szabolcs,
Thanks for your reaction and pointer.
I have been able to download the 3325B service manual you refer to, from
the Agilent website, no problem...
At least now I've got some numbers re. the phase noise. The qualitative
part is well known of course but as Lord Kelvin said...
Apparently, one needed to buy the option 1 version to get phase noise
specified.
Re. Marc: It seems so much out of character (as far as we outsiders know).
It's annoying and spoils my fun watching his videos. Just banning and no
reaction whatsoever to two polite requests for explanation c.q.
restoration to his known email addresses is rude but apparently
in-character.
It's possible that he saw (/youtube shows?) each iteration of the main
message (I edited it maybe five times in quick succession) as a separate
reaction, much like the individual mail messages that we sometimes get
in a digest with each editing change by a poster but resulting in one
changed online post. Online, I only saw just the most recent version.
OTOH, I'm sure he would have recognized it and could have admonished me
to better prepare and not edit my reactions if he wanted.
I've been thinking about contacting Ken but I'd dislike going behind
Marc's back and Ken does not decide what Marc says in his videos. I
can't imagine Ken not seeing (upfront) what I saw, it's not rocket
science (pun intended). In that respect, it's enough for me that I had
the thought and was able to verify it.
Anyway, I've got some quantitative info on the phase noise subject for
the 3325(B, option 1)...
Raymond
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
Several years ago I did phase noise measurements on a 3325B. The
results are here:
The unit had the standard (not high-stability) oscillator and my
measurements showed a dramatic PN improvement using a high-quality
external reference.
John
toggle quoted message
Show quoted text
On 4/14/20 8:50 AM, Raymond Domp Frank wrote: Hi Szabolcs,
Thanks for your reaction and pointer.
I have been able to download the 3325B service manual you refer to, from
the Agilent website, no problem...
At least now I've got some numbers re. the phase noise. The qualitative
part is well known of course but as Lord Kelvin said...
Apparently, one needed to buy the option 1 version to get phase noise
specified.
Re. Marc: It seems so much out of character (as far as we outsiders know).
It's annoying and spoils my fun watching his videos. Just banning and no
reaction whatsoever to two polite requests for explanation c.q.
restoration to his known email addresses is rude but apparently
in-character.
It's possible that he saw (/youtube shows?) each iteration of the main
message (I edited it maybe five times in quick succession) as a separate
reaction, much like the individual mail messages that we sometimes get
in a digest with each editing change by a poster but resulting in one
changed online post. Online, I only saw just the most recent version.
OTOH, I'm sure he would have recognized it and could have admonished me
to better prepare and not edit my reactions if he wanted.
I've been thinking about contacting Ken but I'd dislike going behind
Marc's back and Ken does not decide what Marc says in his videos. I
can't imagine Ken not seeing (upfront) what I saw, it's not rocket
science (pun intended). In that respect, it's enough for me that I had
the thought and was able to verify it.
Anyway, I've got some quantitative info on the phase noise subject for
the 3325(B, option 1)...
Raymond
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
Hi Szabolcs,
Only now it occurs to me that Option 001 is only exactly like the Options 001 in so many HP instruments: High Stability Oscillator (OCXO)! Until now I thought that it (also) contained some special (PLL-) circuitry, tuning or performing whatever trick to be able to spec. the phase noise. I hadn't even looked it up in the catalog...
I'd think the lower phase noise from an OCXO source only applies at higher frequencies, not at frequencies like a few Hz, where apparently, PLL influence drowns out the OCXO's good phase noise specs. At jitter amounts in the tens of ppm's at LF, the only good the OCXO could do is less phase jitter into the PLL (control) circuitry. Is the incoming (reference) phase jitter the main/only component? IOW, is the frequency reference source the main/only cause of the huge phase noise at LF?
Raymond
|
Just as a slight follow-up, it occurred to me that if this pot does go bad, I can replace the plastic resistive component as well as the wiper with parts from a NEW or NOS pot from the same series (they're Clarostat pots). Those parts are interchangeable between standard and concentric pots.
Thanks,
Barry - N4BUQ
toggle quoted message
Show quoted text
----- Original Message ----- From: "Barry" <n4buq@...>
To: [email protected]
Sent: Monday, April 13, 2020 11:09:15 AM
Subject: Re: [HP-Agilent-Keysight-equipment] HP 334A Balance Pots
Understood. It turned out that disassembling the pot wasn't all that
difficult. Maybe I can remember to report back next year... ;)
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "Dave Wise" <david_wise@...>
To: [email protected]
Sent: Monday, April 13, 2020 11:01:03 AM
Subject: Re: [HP-Agilent-Keysight-equipment] HP 334A Balance Pots
That's good news, Barry. I didn't mean to advocate drilling except as a
last
resort. In my case the track was bad, with high end-to-end resistance.
Please report in a year; I'd like to know how well the cleaning persists.
Dave Wise
________________________________________
From: [email protected]
<[email protected]> on behalf of n4buq via groups.io
<n4buq@...>
Sent: Sunday, April 12, 2020 3:03 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 334A Balance Pots
I'm happy to report that I was able to disassemble the noisy pot, clean out
the carbon dust, put a couple of drops of DeoxiT on the moving parts (wish
I
had FaderLub but...) and reassembled it. It works so well now! Glad I
decided to do that.
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "Barry" <n4buq@...>
To: [email protected]
Sent: Friday, April 10, 2020 2:22:53 PM
Subject: Re: [HP-Agilent-Keysight-equipment] HP 334A Balance Pots
I may try prying them open as well so as to be a bit more careful about
how
I'm cleaning things in there.
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "Richard Knoppow" <dickburk@...>
To: [email protected]
Sent: Friday, April 10, 2020 1:45:25 PM
Subject: Re: [HP-Agilent-Keysight-equipment] HP 334A Balance Pots
I have had some luck by prying the covers off for cleaning
and then crimping the tabs back. Can't be done where the pots are
stacked. AB were the best of the bunch are a pain to clean.
Ohmite sold these same pots under their own name. Same for fixed
composition resistors, Ohmite and AB are actually all AB. Ohmite
actually says this in some of its early advertising. I have no
idea what the story behind this was.
On 4/10/2020 11:30 AM, ebrucehunter via groups.io wrote:
Barry,
I have one of these instruments, but it is too buried to easily
allow inspection to determine what type of pots were used.
If the values are above 1k, they are probably not wire-wound.
If they happen to be Allen-Bradley (AB) pots, an age old remedy
is to take a 1/16-inch drill bit and drill a hole in the cover
- in the outer crevice - at the bottom of the pot away from the
terminals. The snout of a can of contact cleaner can then be
inserted in the drilled hole to blast the interior of the pot.
This cleaning will typically last for two or three years and
then you might have to do it again. The access hole remains
available. In drilling the hole, metal chips seem to be pulled
outward and are unlikely to enter the pot. But be careful so
that when the drill bit breaks through, that it does not enter
and damage the pot.
Often these pots can be cleaned by pulling outward on the shaft
-- it will move about 1/16-inch -- while quickly turning the
knob from end to end.
Bruce, KG6OJI
|
5335A keyboard LED interesting thing
Hi,
Sorry if it is know, but it is new to me. While fixing the LED in one
of the keys of my 5335A, I have stumbled upon some interesting thing.
All keys have LEDs in them, even those where the keycap does not have
the transparent insert. So far this is not unusual, as manufacturing
could probably be simpler if one has to deal with only one type of
keys, although I found no particular reason why the actual LED had to
be populated as it is not part of the key mechanism. I was able to
replace it with some fiddling and without removing the switch.
However, what I found is that the Gate Cycle Norm key is supposed to
have no light, but the LED there is actually controlled by the CPU and
it lights up if pressed. I saw it light up when the keyboard was
removed from the instrument front panel for testing and then tried it
with the cap removed to verify.
So likely at the late stages of development sometime, someone decided
that this button should not light, and it was accomplished by
replacing the keycap but not modifying the firmware.
I find this quite amusing.
Szabolcs
|
Re: Application Note 122: EMI Measurement Procedure
They are both ¡°EMI Measurement Procedure¡±, but have different subtitles. See
DaveD
toggle quoted message
Show quoted text
On Apr 14, 2020, at 09:33, Richard Katezansky < rk@...> wrote: Hi,
I have AN142 which goes by the same name.
Are you sure about the number?
Richard
|
Re: HP 3325A Phase noise (and reference clock) as discussed in CuriousMarc's video of Soyuz Clock, Part 6
Hi,
Yes, I somehow expected that without the OCXO option there isn't much
point in specifying phase noise. At least it wouldn't be any stellar
value anyway. The good news is that you can feed it any good quality
10MHz reference and I would assume one could still rely on the phase
noise specification. Since option 001 is nothing than a separate OCXO
which you loop back into the ext ref input on the back panel of the
instrument, I would find it hard to believe that with any other equal
or better reference the 3325A/B would not meet the specification.
Btw if you are still planning to upgrade your instrument, opt 001 is
the same for A and B model and usually you can find a -broken- 3325A
with opt 001 cheaper that the quite rare opt 001 oscillator by itself.
Go figure!
But yeah, I know the feeling when you have an instrument without some
option and the test equipment OCD kicks is to desperately obtain that
missing option, even if there is no other rational reason for it :-)
Szabolcs
Raymond Domp Frank <hewpatek@...> ezt ¨ªrta (id?pont: 2020. ¨¢pr.
14., K, 14:50):
toggle quoted message
Show quoted text
Hi Szabolcs,
Thanks for your reaction and pointer.
I have been able to download the 3325B service manual you refer to, from the Agilent website, no problem...
At least now I've got some numbers re. the phase noise. The qualitative part is well known of course but as Lord Kelvin said...
Apparently, one needed to buy the option 1 version to get phase noise specified.
Re. Marc: It seems so much out of character (as far as we outsiders know).
It's annoying and spoils my fun watching his videos. Just banning and no reaction whatsoever to two polite requests for explanation c.q. restoration to his known email addresses is rude but apparently in-character.
It's possible that he saw (/youtube shows?) each iteration of the main message (I edited it maybe five times in quick succession) as a separate reaction, much like the individual mail messages that we sometimes get in a digest with each editing change by a poster but resulting in one changed online post. Online, I only saw just the most recent version. OTOH, I'm sure he would have recognized it and could have admonished me to better prepare and not edit my reactions if he wanted.
I've been thinking about contacting Ken but I'd dislike going behind Marc's back and Ken does not decide what Marc says in his videos. I can't imagine Ken not seeing (upfront) what I saw, it's not rocket science (pun intended). In that respect, it's enough for me that I had the thought and was able to verify it.
Anyway, I've got some quantitative info on the phase noise subject for the 3325(B, option 1)...
Raymond
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Re: Application Note 122: EMI Measurement Procedure
Hi,
I have AN142 which goes by the same name.
Are you sure about the number?
Richard
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