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Re: 8341B Issues 1992 firmware

 

Couple of things to think about:
1) Is the motherboard the same between the 2804 and 2812 ?
2) What about the PALs on the CPU board
3) Also check that the CAL constand definitions are the same between the versions.

Cheers!

Bruce



Quoting Lothar baier <Lothar@...>:

i am banging my head right now which doesnt happen all too often so maybe somebody here has experienced a similar issue :
i have a 8341B Sweeper ,? the serial# is 2804A and the FW Date is 1982 ,? i am trying to use this sweeper with a 8516A which requires a higher FW revision (May 88)? and also a SN 2812A or higher .
i looked up the changes between 2804 and 2812 and only the CPU board and the sweep board changed so i went on ebay and found a CPU board that already had 1992 firmware installed from a dealer i consider reputable .
The board came in and i installed it in my 8341B tonight , after hitting preset the unit comes up with a start frequency of 100MHz and stop of 200GHz , overmod indicator and unleveled blinking , unit accepts frequency entries but nothing lower than 100MHz .
So i accessed the calibration contants and updated them using the ones from the old board , overmod goes away but unleveled is still blinking and still no lower than 100MHz .
Next i took out the FW EPROMS and put them in the old CPU Board just to experience the same issues , now i took the old FW Eproms and plugged them in the new CPU board and things work fine so the CPU board seems to be fine so the problem seems to be with the FW Eproms , unfortunatly i no longer have a EPROM programmer so i cant download the image and burn new EPROMS .
Question here is now has somebody here installed or tried to install 1992 firmware on a 8340 or 41 and run into the same problems and if so what was the resolution ?
8341B Issues 1992 firmware

Lothar baier
 

i am banging my head right now which doesnt happen all too often so maybe somebody here has experienced a similar issue :
i have a 8341B Sweeper ,? the serial# is 2804A and the FW Date is 1982 ,? i am trying to use this sweeper with a 8516A which requires a higher FW revision (May 88)? and also a SN 2812A or higher .
i looked up the changes between 2804 and 2812 and only the CPU board and the sweep board changed so i went on ebay and found a CPU board that already had 1992 firmware installed from a dealer i consider reputable .
The board came in and i installed it in my 8341B tonight , after hitting preset the unit comes up with a start frequency of 100MHz and stop of 200GHz , overmod indicator and unleveled blinking , unit accepts frequency entries but nothing lower than 100MHz .
So i accessed the calibration contants and updated them using the ones from the old board , overmod goes away but unleveled is still blinking and still no lower than 100MHz .
Next i took out the FW EPROMS and put them in the old CPU Board just to experience the same issues , now i took the old FW Eproms and plugged them in the new CPU board and things work fine so the CPU board seems to be fine so the problem seems to be with the FW Eproms , unfortunatly i no longer have a EPROM programmer so i cant download the image and burn new EPROMS .
Question here is now has somebody here installed or tried to install 1992 firmware on a 8340 or 41 and run into the same problems and if so what was the resolution ???
Re: Low EMI lighting for labs and work areas

 

Loo at these guys. They have a great selection of strip light all run on DC. Used them in my kitchen reno.

http://lightsandparts.com/
Re: HP200CD oscillator

 

On Fri, Mar 4, 2022 at 04:06 PM, Jim Adney wrote:

Hi Jim Adney,

Yes, my? write error R40 is 10K.
The R40 problem is solved, I have another 10K resistor but 15W instead,?that's what i had in my hand
But you raised a good question, why did it burn?
Yes, when I return to the workshop I will check C14 and the other electrolytic.

Do you have a correct 200CD-605 manual and schematic?
Yes I have the correct version for this 200CD in paper, the copy of it was uploaded to BAMA? Anchor and it is out there on NET , I attach a copy of it

Best Regards?
H Capela?

HP200CD_ser605.PDF
HP200CD_ser605.PDF
R40 10K-10W.jpg

Re: Scoping the Power Rails [8566B]

 

Jinxie,

There are 2 external BNC F connectors that give you access to a 10 MHz signal. One of them is directly at the output of the reference oscillator while the other is a divided output of the internal 100 MHz VCXO (which is used with a phase detector to phase lock the VCXO to the reference). The connector labelled "10 MHz OUT" is from the VCXO, NOT the reference. The connector labelled "INT" is directly from the reference, and is the first one you should be checking. I'm attaching two screenshots of my manual. One gives the block diagram that shows this and the other shows the back panel of the instrument where these connections are (the INT connector is next to where it says "Frequency Reference"; I think it's the one on the right, but I'm not sure).

The INT connector is normally jumpered to the EXT connector with a BNC connector. When the switch just above it is set to INT, the oscillator supply for the 10 MHz reference is powered (the oscillator has 2 supplies, for the oven and oscillator). It's powered off when you set it to EXT. You must leave this as INT and power on the unit in order to see that 10 MHz signal. But, that does allow you? direct access to the 10 MHz signal coming out of the reference.

Also, I still think you need to set the scope input impedance to 50ohm to get a valid reading. I once made the mistake of using 1M when checking the internal reference of a microwave counter and saw a similarly mishapen waveform. Setting the input impedance to 50ohm resolved it.

Hope this helps.

Also, I'd hold off on buying any sort of replacement until you're sure this is faulty.

8566_block_diagram.png
8566_rear_panel.png


On Fri, Mar 4, 2022 at 5:24 PM Bruce <bruce@...> wrote:
One solution to consider is a 10 MHz source for all your instruments -?
Leo Bodnar makes a good one for about $90.? That way all your?
instruments see the same reference and will report the same frequency.

You might also need a reference distribution amp depending on how many?
instruments you have.

Cheers!

Bruce

Quoting Jinxie <paul666@...>:

> @Bruce
> It's so frustrating only having a short time every day to look into?
> this problem. I only get enough time to perform a one or two quick?
> checks each time at best. Now it's very late here again and I can do?
> no more today. I'm really liking your suggestion of inserting a?
> clean external 10Mhz signal from a separate source, though! I'll?
> definitely give that a try as it could possibly identify a faulty?
> reference oscillator as the culprit very quickly.
> But that's for the weekend....
>
> @Matt
> I'm not sure what you mean. My analyser seems to only have one 10Mhz?
> output: a BNC socket on the rear panel. The schematic doesn't show?
> any other one, either. Looks like the ref osc is a module that can't?
> be internally tested, which is a damn nuisance. If I can't get at it?
> to repair it then I'm stuck with these greedy fellows on Ebay who?
> charge a mint for these things, which they've ripped out of 'for?
> spares or not working' units for peanuts. Sigh....
>
>
>








Re: Low EMI lighting for labs and work areas

 

I gave up and use LED strip lighting, fluorescent style lamp assemblies.? They emit less noise than?fluorescent lamps did, and I know where the peak is so I live with it.? Mind you, if needed I screw in a pair of incandescent light bulbs and turn off the LED unit.? Quiet, lower light but when taking measurements it's actually easier to read the screens on scopes and spec-ans.

You really can't beat LED sources for the quality of light and if you can live with a little noise you'll be fine as long as you know where the spectral peaks live.? You can always fall back to old style lamps when needed.? Being below ground really helps with other radiated noise short of using a faraday cage approach.? If you need that level of low EMI, then you'll be filtering your AC feeds at the room edge and using a variac on incandescent light bulbs.

I think the idea of a linear supply running 12 VDC LED assemblies designed for a car might also be a great answer.? They do make flat, rectangular emissive surfaces.? That might actually answer my issues in the future (been thinking about it) and enable you to spread the lamps out.? Being flat they can be surface mounted.? Probably look a little mad scientisity, but could be fun.? Brightness is easily varied with the supply voltage (again a linear supply).? For now I can live with the LED assemblies that mount and look like fluorescent lamp assemblies.? They are lighter and easier to install too!

-Chris
Re: HP 8341B RF sweeper has reduced output

 

On Fri, 4 Mar 2022, Sam Reaves wrote:

It is $34 plus $9.99 FedEx Air Special shipping, comes to $43.99 now.
Everything gets more expensive these days, huh? :)

Just purchased 200 too, just in case -- have TWO HP 8340B generators as well
as some other their instruments with attenuators...

If you are talking about the attenuator O rings they are available from The
ORing Store:


I bought 200 for $20.00. Minimum order is $5.00. Now If I can remember
where I put them.......

200 x 0.5mm X 1mm (NBR) Buna-N 70 Duro Metric O-Ring (N0.50X001) $20.00
---------
Sub-Total: $20.00
FedEx Air Special (2 Day Air): $6.99
Total: $26.99



Sam

Sam Reaves
ARS W3OHM
Owner / Moderator of:
LeCroy Owners Group on Groups.io
Sencore Owners Group on Groups.io
Sprint Layout Group on Groups.io
Pulsonix EDA Group on Groups.io
LPKF Owners Group on Groups.io
Electronics and Mechanical Hardware Design Engineering Manager
Staff Scientist Andritz Rolls Global Research Center (RETIRED)




---
*
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
*
Re: Scoping the Power Rails [8566B]

 

One solution to consider is a 10 MHz source for all your instruments - Leo Bodnar makes a good one for about $90. That way all your instruments see the same reference and will report the same frequency.

You might also need a reference distribution amp depending on how many instruments you have.

Cheers!

Bruce

Quoting Jinxie <paul666@...>:

@Bruce
It's so frustrating only having a short time every day to look into this problem. I only get enough time to perform a one or two quick checks each time at best. Now it's very late here again and I can do no more today. I'm really liking your suggestion of inserting a clean external 10Mhz signal from a separate source, though! I'll definitely give that a try as it could possibly identify a faulty reference oscillator as the culprit very quickly.
But that's for the weekend....

@Matt
I'm not sure what you mean. My analyser seems to only have one 10Mhz output: a BNC socket on the rear panel. The schematic doesn't show any other one, either. Looks like the ref osc is a module that can't be internally tested, which is a damn nuisance. If I can't get at it to repair it then I'm stuck with these greedy fellows on Ebay who charge a mint for these things, which they've ripped out of 'for spares or not working' units for peanuts. Sigh....
Re: Scoping the Power Rails [8566B]

 

@Bruce
It's so frustrating only having a short time every day to look into this problem. I only get enough time to perform a one or two quick checks each time at best. Now it's very late here again and I can do no more today. I'm really liking your suggestion of inserting a clean external 10Mhz signal from a separate source, though! I'll definitely give that a try as it could possibly identify a faulty reference oscillator as the culprit very quickly.
But that's for the weekend....

@Matt
I'm not sure what you mean. My analyser seems to only have one 10Mhz output: a BNC socket on the rear panel. The schematic doesn't show any other one, either. Looks like the ref osc is a module that can't be internally tested, which is a damn nuisance. If I can't get at it to repair it then I'm stuck with these greedy fellows on Ebay who charge a mint for these things, which they've ripped out of 'for spares or not working' units for peanuts. Sigh....
Re: Spectrum analyser in a high traffic strong signal environment

Lothar baier
 

¿ªÔÆÌåÓý

Diode limiters do create IM products and the same also applies to YIG filters which also act as limiters if a certain power is exceeded !
It however doesn¡¯t matter much in a practical sense as the job of a limiter usually is to protect a mixer or amplifier from being damaged?


On Mar 4, 2022, at 17:54, Jim Ford via groups.io <james.ford@...> wrote:

?
I don't think so.? Seems like that would defeat the purpose.? Of course, linearity is an illusion after all, so some intermodulation is inevitable.

Jim



Sent from my T-Mobile 4G LTE Device


-------- Original message --------
From: "Ted S via groups.io" <wr4t@...>
Date: 3/4/22 2:24 PM (GMT-08:00)
Subject: Re: [HP-Agilent-Keysight-equipment] Spectrum analyser in a high traffic strong signal environment

Interesting technology thanks for sharing,? does anyone now if this device would generate passive IM products when it goes into limiting?? A diode limiter certainly would.

Ted WR4T

File /856X , 599X Attenuator replacement and cal Battery Replacement Data .txt uploaded #file-notice

[email protected] Notification
 

The following files and folders have been uploaded to the Files area of the [email protected] group.

By: Sam Reaves <sam.reaves@...>

Description:
HP Attenuator O Rings parts & cal memory backup battery also for HP/Agilent/Keysight Analyzers/Generators and stand-alone attenuators.(File Updated 4-MAR-2022
Re: HP 8341B RF sweeper has reduced output

 

If you are talking about the attenuator O rings they are available from The ORing Store:


I bought 200 for $20.00. Minimum order is $5.00. Now If I can remember where I put them.......

200?x0.5mm X 1mm (NBR) Buna-N 70 Duro Metric O-Ring (N0.50X001)$20.00
?---------
Sub-Total:$20.00
FedEx Air Special (2 Day Air):$6.99
Total:$26.99



Sam

Sam Reaves
ARS W3OHM
Owner / Moderator of:
LeCroy Owners Group on Groups.io
Sencore Owners Group on Groups.io
Sprint Layout Group on Groups.io??
Pulsonix EDA Group on Groups.io
LPKF Owners Group on Groups.io
Electronics and Mechanical Hardware Design Engineering Manager
Staff Scientist Andritz Rolls Global Research Center (RETIRED)
Re: Spectrum analyser in a high traffic strong signal environment

 

¿ªÔÆÌåÓý

I don't think so.? Seems like that would defeat the purpose.? Of course, linearity is an illusion after all, so some intermodulation is inevitable.

Jim



Sent from my T-Mobile 4G LTE Device


-------- Original message --------
From: "Ted S via groups.io" <wr4t@...>
Date: 3/4/22 2:24 PM (GMT-08:00)
Subject: Re: [HP-Agilent-Keysight-equipment] Spectrum analyser in a high traffic strong signal environment

Interesting technology thanks for sharing,? does anyone now if this device would generate passive IM products when it goes into limiting?? A diode limiter certainly would.

Ted WR4T

Re: HP200CD oscillator

 

The cathode current of V1 and V3 is through R40.
Re: Spectrum analyser in a high traffic strong signal environment

 

Interesting technology thanks for sharing,? does anyone now if this device would generate passive IM products when it goes into limiting?? A diode limiter certainly would.

Ted WR4T
Re: Low EMI lighting for labs and work areas

 

I'd vote with the "run 'em on clean DC" crowd, for lowest added interference. The key word though, is "added" - we're already awash in EMC interference from almost all electronic equipment around, so percentage-wise, it may hardly matter. All line-powered LED bulbs and fixtures that I've studied, above about a few W actual input power, use some sort of SMPS, so some noise is guaranteed.

Over the past couple years, I've been replacing under-cabinet fluorescent fixtures with nice low voltage LED strips that run on 24 VDC actual, but that comes from a SMPS wall-wart provided in the kit. You can find all sorts of LV LED strips and fixtures, and make your own DC, but again, the practicality versus relative EMC improvement comes into play.

Another complication is finding the right sort of fixtures in the right color temperatures. I try to get 2700-3300 K for general indoor lighting, since it's close to the old incandescent bulbs, and easy on the eyes. For overhead task lighting, up to 4000 K or so seems OK to me. I wouldn't go much higher, unless CRI needs to be very good - I consider the 6500 K ones only good for outdoor flood lighting.

Lastly, for close-in task lighting, you want the light to be well diffused. If you get LED ones that are just a cluster of point sources, that image will reflect off of everything, and be very irritating. When I did the LED under-cabinet lights in our kitchen years ago, I found that the LED point source types reflected right off the counter tops, very offensively. I searched far and wide, and finally found some that were right, with great diffusers, and about 3000 K - they were the most expensive ones, of course. When I needed some more, more recently, I found they had disappeared off the market, so I had to find alternatives. These little strip ones that I found have awesome diffusion, but are a bit on the hot side, maybe 4000 K.

Ed
Re: Scoping the Power Rails [8566B]

 

A few thoughts:

1. Are you checking the INT connector or the 10 MHz out? The INT
connector is directly at the output of the oscillator. I'd see what
that gives you. If that looks good and the 10 MHz out doesn't, you'll
want to look at the M/N reference assemblies.
2. Make sure you use 50ohm input impedance on the scope.
3. I'd also change your horizontal scale so you only display a few
periods. This is a minor nit, but it will be a bit easier to see
what's going on with that waveform.

Matt

On Fri, Mar 4, 2022 at 12:26 PM Michael Perkins <terman08@...> wrote:

Should be a clean sine wave. I would replace this oscillator with one that has a sinusoidal output. There are two many zero crossings and this signal will probably get ¡°squared up ¡° into a square wave.
Mike

On Fri, Mar 4, 2022 at 12:23 PM Bruce <bruce@...> wrote:

I'm not sure if this is the cause (probably) but it depends on how the
100 MHz reference interprets it.

Can you connect to an external 10MHz source (possible from one of your
other instruments internal reference0?
Quoting Jinxie <paul666@...>:

Gentlemen,

Following advice here, I decided to first check the 10Mhz frequency
of the reference oscillator to see if it had drifted and was rather
surprised to see it come out on my frequency counter as 20Mhz. So
only out by 10Mhz, then! I then connected it to my scope and got the
trace shown below. Oddly enough, the ref oscillator warning on the
screen went out when it was warmed up, so part of the analyzer at
least didn't have a problem with this! The YTO unlock error message
was still there, though.
Any suggestions? Could this weird ref trace be the cause of the YTO unlock?

Measured directly from the BNC at the rear of the analyzer on a 1:1 basis.
Re: Scoping the Power Rails [8566B]

 

Should be a clean sine wave. I would replace this oscillator with one that has a sinusoidal output. There are two many zero crossings and this signal will probably get ¡°squared up ¡° into a square wave.
Mike

On Fri, Mar 4, 2022 at 12:23 PM Bruce <bruce@...> wrote:
I'm not sure if this is the cause (probably) but it depends on how the?
100 MHz reference interprets it.

Can you connect to an external 10MHz source (possible from one of your?
other instruments internal reference0?
Quoting Jinxie <paul666@...>:

> Gentlemen,
>
> Following advice here, I decided to first check the 10Mhz frequency?
> of the reference oscillator to see if it had drifted and was rather?
> surprised to see it come out on my frequency counter as 20Mhz. So?
> only out by 10Mhz, then! I then connected it to my scope and got the?
> trace shown below. Oddly enough, the ref oscillator warning on the?
> screen went out when it was warmed up, so part of the analyzer at?
> least didn't have a problem with this! The YTO unlock error message?
> was still there, though.
> Any suggestions? Could this weird ref trace be the cause of the YTO unlock?
>
> Measured directly from the BNC at the rear of the analyzer on a 1:1 basis.
>
>
>








Re: Low EMI lighting for labs and work areas

Gary Johnson
 

I maintain a short list of known-quiet devices including lightning and power supplies. Creating an extensive list with exact model numbers is a fool¡¯s errand. Manufacturers change the internals of their products without notice. What was good last year may be a disaster this year. You MUST buy and test sample fixtures before committing.



Gary NA6O?
Re: Scoping the Power Rails [8566B]

 

I'm not sure if this is the cause (probably) but it depends on how the 100 MHz reference interprets it.

Can you connect to an external 10MHz source (possible from one of your other instruments internal reference0?
Quoting Jinxie <paul666@...>:

Gentlemen,

Following advice here, I decided to first check the 10Mhz frequency of the reference oscillator to see if it had drifted and was rather surprised to see it come out on my frequency counter as 20Mhz. So only out by 10Mhz, then! I then connected it to my scope and got the trace shown below. Oddly enough, the ref oscillator warning on the screen went out when it was warmed up, so part of the analyzer at least didn't have a problem with this! The YTO unlock error message was still there, though.
Any suggestions? Could this weird ref trace be the cause of the YTO unlock?

Measured directly from the BNC at the rear of the analyzer on a 1:1 basis.
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