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  1. HP-Agilent-Keysight-Equipment
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Expanded Topics Messages
Date
Re: VNA Reference Impedance Renormalization

 

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Hi.

Just me, or is there a bit of an inconsistency on page one of that PDF?

Between the text descriptions and the illustration below, regarding how to measure Low, Medium and High impedance DUT's.?? I think the order of the text descriptions and the illustrations are different.

Also, the first illustration surely is a S11 measurement, not S21.

Yes, No??? If no, why, in detail please.

73.

Dave 'KBV.
Re: HP8648A - attenuator glitches

 

Digging a little deeper into the Service Manual, the output attenuator assy (& Reverse Power Protection- RPP) are quite different between the 1GHz -A and the -B, -C & -D higher frequency models.
For the -A 1GHz model, the attenuator & RPP module is A7 with p/n 08647-61803.
For the -B, C, & D models, the attenuator is A11 with p/n 33222-60011 while the separate RPP module has p/n? 08648-60025.
?
Both the -A (1GHz) and B,C,D (2, 3 & 4 GHz) models are shown in the Service Manual drawings as "130dB attenuators in 10dB steps".
The B,C,D models use the 33222 attenuator which uses plungers & O-rings but the -A version possibly uses a simpler attenuator construction (ie no O-rings or plungers) and incorporates the RPP circuitry, so it has a different p/n.?
?
UPDATE: it seems the 10dB increments also 'glitch' at the 50 & 60dB settings. I can't hear any mechanical clicks when the attenuator encoder is changed (with the covers on), so do I have a dicky/dirty/ encoder ?? (I'd still like to know how the sub-decade attenuator levels are achieved !? ?The plot thickens.
?
Kit
?
?
Re: VNA Fixtures

 

I suspect what you have there are RF/IF transformer(s)?with tuned primary and untuned secondary.?
?
If there is a tap on the primary, the center pin of the three pin side, it is used to feed supply voltage to
the active device.?
?
I would remove one side of the primary dog bone cap and take a low frequency?
measure of the primary and secondary inductance values. Get this from a S11 shunt measurement.
?
Then while taking? a measurement of the primary inductance (S11), place a short circuit on the secondary side
and re measure the shift in the primary L value, again from S11. The primary L value should decrease and this?
shift in L provides the coupling coefficient. This value obtained from SQRT [(1-L_primary_sc/L_primary_oc)]. Again,
primary L is the measurement, shunt mode, S11.... while the secondary is OC and then SC.?
?
Given all this one can ascertain the frequency response analytically with the dog bone C value provided and?
an assumption on the secondary termination Z.?
Re: Looking for 54300A operating and service manual

 

Thanks, but that is the operating and programming manual which, as I stated, does not have the information I seek.

Peter

On 2/20/2025 8:40 PM, scm325 via groups.io wrote:


--------------------------------------------------------------------------------
*From:* [email protected] <[email protected]> on behalf of Peter Gottlieb via groups.io <hpnpilot@...>
*Sent:* Thursday, February 20, 2025 2:17 PM
*To:* [email protected] <[email protected]>
*Subject:* [HP-Agilent-Keysight-equipment] Looking for 54300A operating and service manual
Nothing on Keysight, no luck with a web search.? I have the operating
and programming manual but it doesn't help.

What I'm really after is the pinout for the plug in modules as I would
like to use them stand-alone.

Peter
Re: Looking for 54300A operating and service manual

 

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Sorry about that didn't read Peters entire post.

From: [email protected] <[email protected]> on behalf of scm325 <Highpwr@...>
Sent: Thursday, February 20, 2025 5:40 PM
To: [email protected] <[email protected]>
Subject: Re: [HP-Agilent-Keysight-equipment] Looking for 54300A operating and service manual
?

From: [email protected] <[email protected]> on behalf of Peter Gottlieb via groups.io <hpnpilot@...>
Sent: Thursday, February 20, 2025 2:17 PM
To: [email protected] <[email protected]>
Subject: [HP-Agilent-Keysight-equipment] Looking for 54300A operating and service manual
?
Nothing on Keysight, no luck with a web search.? I have the operating
and programming manual but it doesn't help.

What I'm really after is the pinout for the plug in modules as I would
like to use them stand-alone.

Peter
Re: Looking for 54300A operating and service manual

 

开云体育


From: [email protected] <[email protected]> on behalf of Peter Gottlieb via groups.io <hpnpilot@...>
Sent: Thursday, February 20, 2025 2:17 PM
To: [email protected] <[email protected]>
Subject: [HP-Agilent-Keysight-equipment] Looking for 54300A operating and service manual
?
Nothing on Keysight, no luck with a web search.? I have the operating
and programming manual but it doesn't help.

What I'm really after is the pinout for the plug in modules as I would
like to use them stand-alone.

Peter
Looking for 54300A operating and service manual

 

Nothing on Keysight, no luck with a web search.? I have the operating and programming manual but it doesn't help.

What I'm really after is the pinout for the plug in modules as I would like to use them stand-alone.

Peter
Re: Test Set Program Development Tool DEV_PL on 3.5" floppy

 

USB floppy drives do not implement a full floppy controller. I’ve never seen one that can handle other than 512 byte sectors, and or sector counts other than those used on MS-DOS 720K and 1.44MB formats. Even there, there is an issue with coercivity on media and head width that create problems with actually using 720K formats.
?
As such, you’re going to need a laptop or desktop with an actual internal floppy. (A laptop that uses an external floppy with a 26+ pin cable rather than USB will likely work as well).
HP 3403C True RMS Voltmeter display fault

 

Hello,
This is my first post here, thanks for allowing me in. I've had the chance to pick up an HP3403C True RMS voltmeter, serial 1452A03359, with options 0011 (Autoranging) and 006 (dB display).
I bought it with its condition unknown. I know some of the parts inside are absolutely not replaceable but for the price it was a bet I wanted to make.
?
So it came in the mail. It must have spent the last few years of its existence in a cellar as it had some slight facia corrosion damage, and absolute STINKS of mold. I have cleaned it thoroughly but it still smells a bit inside.??
The display is stuck on displaying +1V, blinking. If I set the speed to fast it blinks a bit faster. Sometimes it'll display rubbish until the next power off/on again. It seems to react to the switches as the comma moves with the ranges and the dB display also lights up. I have checked the power supply lines (following the procedure), they're good and I can't see much ripple on my oscillo. I'll replace the capacitors of the power supply but only when I know it works as to avoid unnecessary spending.
I have removed all the boards in it (converter and options) only leaving the motherboard, PSU and the display unit and it is still stuck. I therefore believe the issue is not converter related but display related. The display is basically a 3.1/2 digit DVM built around a LD110 (digital processor), LD111 (analog processor) and an SN74LS47N decoder for the displays. , and
?
I'm quite the beginner and lack some diagnostics knowledge. The display is also a rather convoluted assembly. Considering the high humidity storage it went through I suppose solder corrosion is not out of the question. I have already cleaned what I could (the boards were all perfect thought) and the gold plated connectors (also perfect) with isoprop.?

What would be your recommendations on what to try next?
Thanks everyone,
Arnaud.
?
Re: VNA Fixtures

 

It runs fine under Fedora linux using WINE.
--
T. Gerbic
Central California
Re: Service manual scan post processing

 

I pretty much just follow this guide:


Which can be confusing at times (wording is not totally clear at some points). Especially after you create the control points, you have to do this strange zoom, move, and crop, and hope everything turns out OK. And the preview it creates durng the process will look like crap- you have to remember to click "Calculate Optimal Size" at the end.

I have definitely had Hugin not connect some schematic lines before, and some schematics have been completely unsuccessful using it, but have had successes elsewhere. To my knowledge, it hasn't connected any lines incorrectly, that could be a control points issue.

-Michael


On Thu, Feb 20, 2025 at 02:59 Tom Gardner via <tggzzz=[email protected]> wrote:
On Thu, 20 Feb 2025 at 07:14, Michael Bierlein via <bierl008=[email protected]> wrote:
I use software called Hugin. Bit of a learning curve, but works semi-reliably after you get it down.

I've tried hugin for schematics, and was unsuccessful: many of the continuous lines were no longer continuous, and it connected some lines incorrectly. What settings did you use for the stitching?
Re: VNA Reference Impedance Renormalization

 

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Here’s a link to an interesting article that may help. ?I thought it was helpful to know the error bounds for different circuit configurations when using a 50 ohm network analyzer to measure low and high resistances. ?HTH.


Jim Ford
Laguna Hills, California, USA


On Feb 18, 2025, at 3:51?PM, Brian Beezley <k6sti@...> wrote:

?If you use a VNA to characterize devices such as IF transformers, crystal filters, or ceramic filters, normally you add series resistance to the 50 ohm VNA ports so that the device sees its design impedance, which is usually much higher. This lets you measure the true response, but the resistors will reduce the dynamic range. You can use matching transformers instead of resistors to avoid this, but you may not have what you need on hand. The transformers must have enough bandwidth not to affect the device response.

I've written a little program that renormalizes the S-parameter reference impedance to whatever the device needs. This lets you make a 50 ohm measurement and then see how the device would respond had it been driven and loaded by the correct impedance. If you record all four S-parameters, the renormalization will undo the effects of improper filter source and load impedances even for devices that are not perfectly symmetrical (reversing them changes the response). However, the program assumes the proper renormalized impedance is the same for input and output. This is not true of some IF transformers, for example.

The renormalization program is listed at the top of this page:

http://ham-radio.com/k6sti/mu.htm

See the bottom of the page for downloading instructions.

Brian





Re: VNA Fixtures

 

Great, thanks for the clarification.

Re: 8596E Spectrum Analyzer Fault

 

Thank you, Mark. I would have thought if it was the power supply then the issue would arise spontaneously at any time and not just precisely when I try to enter a frequency limit. But I may be wrong. For sure the keys are very dirty judging by the amount of pressure required to get them to actuate, so I shall clean them first in any event, since they certainly need it. I'll follow up with the other tests once that's out of the way and if the problem persists.
?
J.

Re: 8596E Spectrum Analyzer Fault

 

This doesn't sound like a dirty keyboard issue to me. ?Before digging into the keyboard for cleaning, I would get it in this state and then unplug the keyboard to see if the issue continues.
?
I think the processor has gotten swamped dealing with something unexpected. ?Maybe it's busy responding to a peripheral issuing high speed erroneous interrupts, or stuck in a high-priority loop waiting for a response from a peripheral.
?
Missed interrupts because the processor is busy with higher priority tasks would explain why the oven is taking longer than usual. ?There's no sensor checking the oven temperature; it's just a timer and that's likely interrupt driven.
?
The keyboard appears to be polled (and not interrupt driven) which is why I think it's not a primary suspect.? I definitely agree the power supply is the first thing to check.
?
-mark
?
?
On Wed, Feb 19, 2025 at 01:11 PM, Jinxie wrote:

Hi guys,
?
In the course of investigating some IFTs today, I fired up my 8596E, which started-up normally and displayed the usual min thru ~12Ghz spectrum. However, when I tried to enter the frequency range I wanted to study, it froze up and just would not respond. I was able to enter the start frequency okay, but the very second I entered the stop one, it just locked-up and became super-sluggish and unresponsive to any further input. At the instant, I got a "FREQ UNCAL" message appear on the screen. A *possible* clue is the 'OVEN' message takes a lot longer to go away than it has previously when it was all working fine. However, even when fully warmed up, I am still experiencing the thing freezing-up as described above.
Any ideas what the fault might be?
?
Cheers,
Jinxie

Re: HP 8670B amplifier - does it ring a bell with anyone?

 

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Well, I’m not familiar with the 8670B amp, but I have run across the HP 8349B 2 to 20 GHz amps. ?According to a very knowledgeable friend, the 8349s were designed for driving mmWave multipliers. ?Not too impressive these days with output power of only around +20 dBm, but it was a big deal back in the 1970s to the 1990s. ?Now it’s a 4 by 4 mm MMIC for about $150. ?I bet those 8349s went for kilobucks back in the day. ?Sorry I couldn’t be of more help.

Jim Ford
Laguna Hills, California, USA


On Feb 18, 2025, at 6:43?PM, F1EKU via groups.io <rfconsulting.fr@...> wrote:

?
The picture to illustrate my previous remark...
<hp-8760b-k29-photo-2 - copie.jpg>

Re: VNA Fixtures

 

Yes, jumper across your test fixture, center to center, shield to shield.

Re: WTB: Manual for Dymec 2411A Guarded Data Amplifier accessory for HP 2401C Voltmeter.

 

You might want to post your request on the Manual Exchange group.

DaveD
KC0WJN


On Thu, Feb 20, 2025 at 02:26 Terry Gains via <terry.waihi=[email protected]> wrote:
Hello,

Would anyone have a manual for the Operating & Service Manual for the Dymec 2411A Guarded Data Amplifier?that they could sell?

Kind regards,
Terry
Bloomington, MN 55420
?

Re: Service manual scan post processing

 

On Thu, 20 Feb 2025 at 07:14, Michael Bierlein via <bierl008=[email protected]> wrote:
I use software called Hugin. Bit of a learning curve, but works semi-reliably after you get it down.

I've tried hugin for schematics, and was unsuccessful: many of the continuous lines were no longer continuous, and it connected some lines incorrectly. What settings did you use for the stitching?

WTB: Manual for Dymec 2411A Guarded Data Amplifier accessory for HP 2401C Voltmeter.

 

Hello,

Would anyone have a manual for the Operating & Service Manual for the Dymec 2411A Guarded Data Amplifier?that they could sell?

Kind regards,
Terry
Bloomington, MN 55420
?

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