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Date
Re: 8350B w/83590A repair advice

 

Mark:

Just remember that on the 8350 plug ins, there is no frequency lock. So, I would estimate the frequency drift you see there is really nice for these.

Dan in Chandler, AZ
Re: HP 8970B noise figure meter with E18 (gone!)

 

¿ªÔÆÌåÓý

Nice work!!!

Regards,

?

Stephen Hanselman

Datagate Systems, LLC




On Dec 18, 2019, at 00:41, Martin <musaeum@...> wrote:

?Hi all,

E18 has gone once I changed the DAC converter, the one for fine-tuning the first LO. I realigned the unit and everything looks fine - I just cannot use it since I do not have a noise source... even a cheap one.

I only managed to get an SMD-Version of the DAC, so I had to do some artistical wiring work to put it in, see the picture attached. At the end, to get the board back in place, I had to take off one of the rubber bumpers on the Isolator - it was just underneath the DAC and probably touching the original one.

cheers, merry Christmas, happy new Year!
Martin

<P1240406 _MAX converter_.jpg>
Re: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

Highly recommend ABBYY Fine Reader Pro(commercial $199) and/or their cloud service offering($30/month for 500 pages) that couldn't be easier to use. You pay per $0.06 page. I've used for both personal and professional use, and I've always been happy with the recognition.

My general use for OCR has to do with creating searchable indexable text associated with still-available original graphics. This method lets me locate the document in question via grep/text search, and then I view the original PDF/JPG/whatever. I'm not exactly "converting" a block of, say, code, from graphics to something directly importable where higher accuracy is more important.

Alternatively, tesseract is free on linux, and does a decent job.

No matter which of the two you choose, you should make sure to have the highest quality scans (400 DPI is a common target minimum) both in terms of resolution, but also image quality like flatness, square to camera (if not using a scanner), eliminating hotspots and reflections, and so on. Take advantage of the training features of these software packages.

Context-sensitive OCR is definitely a thing. Abbyy can do document classification, where it recognizes which "type" of document you've submitted, and then applies certain rules to those types of documents. I don't know the details here and have never used the feature, however.

I've always been impressed with Abbyy --- no other association other than satisfied customer. Their support for more than 200 languages (ok, I use exactly one, generally) seems pretty darn impressive to me.

Keith

On 12/18/2019 10:09 AM, Chuck Harris wrote:
I think you are old enough to remember that typewriters, by design,
used the "l" as the number "1"... certainly all manual typewriters,
and most (all?) early non IBM electric typewriters...

Even the IBM Selectric carried that convention into the 1970's. I
had an old Selectric I that had 3 figures on the "1" key, "[", "]",
and "1". What was printed depended on the typeball installed in the
typewriter. On mine it wasn't a "1".

It wasn't until teletypes and computers came around that the keyboard
got its own separate "1" digit.

Everything you said about OCR is spot on. Newer OCR engines do have
contextual awareness, but like in most areas of life, we engineers
are outside of the conventional contexts of life. We operate in the
underpinnings and fringes that most folks don't even know exist.

I have a "T" shirt with the statement:

ENGINEER
Solving problems you didn't know you had in ways you can't understand.

I think it was meant to be insulting... but I am not sure who they
were trying to insult.

-Chuck Harris

ArtekManuals wrote:
The biggest problem with OCR especially with manuals is that The OCR engine unlike we
humans is not context sensitive, for example often"I" ,"l" and "1" (pronounced ,
eye , el and one) are confused by the OCR engine ("B" and "8: are the next
candidates). This is particularly problematic on Schematics and especially HP parts
lists which were often printed with a tiny 6pt font. OCR engines are designed with
text dialogue and news paper column in mind. Schematics are also a big problem as a
result because the OCR engine doesn't always know what to do with R101 ( was that an
"O" or a "0" ) hanging out in space and not part of sentence. You and I reading it
know that is R101 and not RLOL because we read it in context. Hp at one point made it
even worse as the font they used was identical for lower case "L" and the number "1"

Dave
ArtekManuals
Re: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

I think you are old enough to remember that typewriters, by design,
used the "l" as the number "1"... certainly all manual typewriters,
and most (all?) early non IBM electric typewriters...

Even the IBM Selectric carried that convention into the 1970's. I
had an old Selectric I that had 3 figures on the "1" key, "[", "]",
and "1". What was printed depended on the typeball installed in the
typewriter. On mine it wasn't a "1".

It wasn't until teletypes and computers came around that the keyboard
got its own separate "1" digit.

Everything you said about OCR is spot on. Newer OCR engines do have
contextual awareness, but like in most areas of life, we engineers
are outside of the conventional contexts of life. We operate in the
underpinnings and fringes that most folks don't even know exist.

I have a "T" shirt with the statement:

ENGINEER
Solving problems you didn't know you had in ways you can't understand.

I think it was meant to be insulting... but I am not sure who they
were trying to insult.

-Chuck Harris

ArtekManuals wrote:

The biggest problem with OCR especially with manuals is that The OCR engine unlike we
humans is not context sensitive, for example often"I" ,"l" and "1" (pronounced ,
eye , el and one) are confused by the OCR engine ("B" and "8: are the next
candidates). This is particularly problematic on Schematics and especially HP parts
lists which were often printed with a tiny 6pt font. OCR engines are designed with
text dialogue and news paper column in mind. Schematics are also a big problem as a
result because the OCR engine doesn't always know what to do with R101 ( was that an
"O" or a "0" ) hanging out in space and not part of sentence. You and I reading it
know that is R101 and not RLOL because we read it in context. Hp at one point made it
even worse as the font they used was identical for lower case "L" and the number "1"

Dave
ArtekManuals
Re: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

Aparently humans are almost as prone to this. I don't know how many HP410B VTVMs I've seen advertised as an HP4108.

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "ArtekManuals" <manuals@...>
To: [email protected]
Sent: Wednesday, December 18, 2019 8:26:44 AM
Subject: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC -
Ohms Converter

The biggest problem with OCR especially with manuals is that The OCR
engine unlike we humans is not context sensitive,? for example often"I"
,"l" and "1"? (pronounced , eye , el and one) are confused by the OCR
engine ("B" and "8: are the next candidates). This is particularly
problematic on Schematics and especially HP parts lists which were often
printed with a tiny 6pt font. OCR engines are designed with text
dialogue and news paper column in mind. Schematics are also a big
problem as a result because the OCR engine doesn't always know what to
do with R101 ( was that an "O" or a "0" ) hanging out in space and not
part of sentence. You and I reading it know that is R101 and not RLOL
because we read it in context. Hp at one point made it even worse as the
font they used was identical for lower case "L" and the number "1"

Dave
ArtekManuals



On 12/18/2019 9:01 AM, David C. Partridge wrote:

I use the OCR in Acrobat Pro on the scans I¡¯ve done (FWIW).

*From:*[email protected]
[mailto:[email protected]] *On Behalf Of *Terry
Gains
*Sent:* 18 December 2019 12:20
*To:* [email protected]
*Subject:* Re: [HP-Agilent-Keysight-equipment] 2401C Integrating
Digital Voltmeter and 2410B AC - Ohms Converter

Hi David,

Absolutely correct and I'd certainly persist with OCR if I was getting
good results.

--
Dave
Manuals@...
www.ArtekManuals.com
Re: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

Yes entirely so - rather like feeding a spell checker with Lewis Carroll's
Jabberwocky (try it some day).

D.

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of ArtekManuals
Sent: 18 December 2019 14:27
To: [email protected]
Subject: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C
Integrating Digital Voltmeter and 2410B AC - Ohms Converter

The biggest problem with OCR especially with manuals is that The OCR
engine unlike we humans is not context sensitive,? for example often"I"
,"l" and "1"? (pronounced , eye , el and one) are confused by the OCR
engine ("B" and "8: are the next candidates). This is particularly
problematic on Schematics and especially HP parts lists which were often
printed with a tiny 6pt font. OCR engines are designed with text
dialogue and news paper column in mind. Schematics are also a big
problem as a result because the OCR engine doesn't always know what to
do with R101 ( was that an "O" or a "0" ) hanging out in space and not
part of sentence. You and I reading it know that is R101 and not RLOL
because we read it in context. Hp at one point made it even worse as the
font they used was identical for lower case "L" and the number "1"

Dave
ArtekManuals



On 12/18/2019 9:01 AM, David C. Partridge wrote:

I use the OCR in Acrobat Pro on the scans I¡¯ve done (FWIW).

*From:*[email protected]
[mailto:[email protected]] *On Behalf Of *Terry
Gains
*Sent:* 18 December 2019 12:20
*To:* [email protected]
*Subject:* Re: [HP-Agilent-Keysight-equipment] 2401C Integrating
Digital Voltmeter and 2410B AC - Ohms Converter

Hi David,

Absolutely correct and I'd certainly persist with OCR if I was getting
good results.

--
Dave
Manuals@...
www.ArtekManuals.com
Re: HP 8970B noise figure meter with E18 (gone!)

 

On 12/18/19 2:41 AM, Martin wrote:
I had to do some artistical wiring work to put it in
That is some fine solder sculpture!
Re: Wanted: HP 3458a DVM in non-working condition

 

For most people a HP3457A will be quite adequate if not quite as high of resolution. And much cheaper! But what bean counter struck off the display backlight?
Kjo
OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

The biggest problem with OCR especially with manuals is that The OCR engine unlike we humans is not context sensitive,? for example often"I" ,"l" and "1"? (pronounced , eye , el and one) are confused by the OCR engine ("B" and "8: are the next candidates). This is particularly problematic on Schematics and especially HP parts lists which were often printed with a tiny 6pt font. OCR engines are designed with text dialogue and news paper column in mind. Schematics are also a big problem as a result because the OCR engine doesn't always know what to do with R101 ( was that an "O" or a "0" ) hanging out in space and not part of sentence. You and I reading it know that is R101 and not RLOL because we read it in context. Hp at one point made it even worse as the font they used was identical for lower case "L" and the number "1"

Dave
ArtekManuals

On 12/18/2019 9:01 AM, David C. Partridge wrote:

I use the OCR in Acrobat Pro on the scans I¡¯ve done (FWIW).

*From:*[email protected] [mailto:[email protected]] *On Behalf Of *Terry Gains
*Sent:* 18 December 2019 12:20
*To:* [email protected]
*Subject:* Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

Hi David,

Absolutely correct and I'd certainly persist with OCR if I was getting good results.

--
Dave
Manuals@...
www.ArtekManuals.com
Re: 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

¿ªÔÆÌåÓý

I use the OCR in Acrobat Pro on the scans I¡¯ve done (FWIW).

?

From: [email protected] [mailto:[email protected]] On Behalf Of Terry Gains
Sent: 18 December 2019 12:20
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

?

Hi David,

Absolutely correct and I'd certainly persist with OCR if I was getting good results.
Re: 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

Hi David,

Absolutely correct and I'd certainly persist with OCR if I was getting good results. OCR with newer manuals may be less of a problem, but the only scanner I own, a HP OfficeJet Pro 8710, really struggles to recognise text from older, yellowed, faded, and well thumbed pages.?The OCR on that device always needs plenty of manual correction, especially with data presented in tables, captions and footers, and it's not always happy working with text layed out in two columns.

Maybe I'm not using the OCR correctly, but the time taken to scan and then reassemble the jigsaw of OCR always seems more than the time taken just typing at 80 words per minute.

To all of you getting good results with OCR: I am insanely jealous!

Kindest and warm regards,
Terry
Re: 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

¿ªÔÆÌåÓý

Why re-type ¨C that¡¯s surely what OCR is for?

?

From: [email protected] [mailto:[email protected]] On Behalf Of Terry Gains
Sent: 18 December 2019 10:06
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

?

Hi Dave,
:
:
3) ¡­ When scanning a manual, I usually re-type the text, instead of just imaging the whole page

Re: 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter

 

Hi Dave,

Sorry for the late reply.

"Any idea if that manual has been scanned? A quick Google doesn't turn it up anywhere."
I've found no scanned copies of the 2410B manual looking around the usual places on the net, which leaves few options.

1) There are some service manual reproduction companies with proper copyright permission that are open to requests of what other manuals they should offer. I used one such company today, ArtekManuals.com. For $12.95 I got a scanned copy of a rare HP 5376A Programmer manual for the HP 5360A computing counter. In this case, I was wondering what it would take to substitute a small single board computer, such as a Raspberry PI 4, in place of the ultra rare HP 5376A programer. As expected, it's a fascinating document, but I'll have to throw many many hours at it just to plan a result. I'll ask ArtekManuals if they will scan a?2410B manual and get back to you with a PM.

2) If you haven't tried it, there is a group called?[manualexchange] where you could ask.

3) If your prepared to wait till about late Jan or early Feb, I'll e-mail you a copy of my yet-to-be scanned manual. When scanning a manual, I usually re-type the text, instead of just imaging the whole page, as this allows the reader to do a word search. Images of circuit diagrams etc are still scanned from the original manual. Images of circuit boards don't always scan well, so I substitute high resolution colour photos if I have the actual boards. But the goal is always to have a verbatim copy that's indistinguishable from the original in fonts, layouts and page count.?

Kind regards,
Terry.
Re: HP 8970B noise figure meter with E18 (gone!)

 

Hi all,

E18 has gone once I changed the DAC converter, the one for fine-tuning the first LO. I realigned the unit and everything looks fine - I just cannot use it since I do not have a noise source... even a cheap one.

I only managed to get an SMD-Version of the DAC, so I had to do some artistical wiring work to put it in, see the picture attached. At the end, to get the board back in place, I had to take off one of the rubber bumpers on the Isolator - it was just underneath the DAC and probably touching the original one.

cheers, merry Christmas, happy new Year!
Martin
Re: Wanted: HP 3458a DVM in non-working condition

 

Hello,

you also need to keep one more thing in mind which is bad for these seeking a cheap 3458A.

If you take a completely beat up one, and a decent lawyer, Keysight will - AFAIK - repair it for a reasonable set fee. This essentialy gives a new multimeter and puts a very high minimal bound on sales prices. If I would find a 3458A in the bin tomorrow and it was shot up with a Gepard rifle and was urinated on by both fox and female, as long as I can find all the parts, I would try to get Yaniv to force KS to honor its repair policy and flog the result on ebay.


Something I have had a lot of fun with is SolarTron. But I am not a big voltnut, my 7061 recently failed and I dont miss it so my wife balks heavily at the cal and repair cost.


Tam



With best regards
Tam HANNA

Enjoy electronics? Join 15k7 other followers by visiting the Crazy Electronics Lab at

On 2019. 12. 17. 18:47, Reginald Beardsley via Groups.Io wrote:
My reaction when I read the subject title was, "Yeah, you and a few hundred others."

The recent introduction of the RoHS "black" edition indicates that Keysight isn't planning to replace the design. Old designs which are still in production hold their value well. The 34401A continued in production for an unusually long time because it was stipulated in so many test equipment lists in service manuals.

I picked up a couple of 34401As via ebay for ~$250 each. One was wonky. The cause was solder flux from an old repair. I cleaned it with isopropyl and it is the best of the pair. That's about 25% of the cost of the new equivalent. There are several on ebay now which will sell in the $200-300 price range. The same valuation puts an easily repairable 3458A at $2350. And an incomplete unit whether missing or unrepairable board at ~$1000-1500 as a parts mule. Provided it's not a set of known bad boards.

A working 3458A is worth $3000-5000. With RoHS compliant models available, there should be a drop in price on older units. But not likely to be huge.

Volt nutting has become rather fashionable.

Have Fun!
Reg
Re: Wanted: HP 3458a DVM in non-working condition

 

My reaction when I read the subject title was, "Yeah, you and a few hundred others."

The recent introduction of the RoHS "black" edition indicates that Keysight isn't planning to replace the design. Old designs which are still in production hold their value well. The 34401A continued in production for an unusually long time because it was stipulated in so many test equipment lists in service manuals.

I picked up a couple of 34401As via ebay for ~$250 each. One was wonky. The cause was solder flux from an old repair. I cleaned it with isopropyl and it is the best of the pair. That's about 25% of the cost of the new equivalent. There are several on ebay now which will sell in the $200-300 price range. The same valuation puts an easily repairable 3458A at $2350. And an incomplete unit whether missing or unrepairable board at ~$1000-1500 as a parts mule. Provided it's not a set of known bad boards.

A working 3458A is worth $3000-5000. With RoHS compliant models available, there should be a drop in price on older units. But not likely to be huge.

Volt nutting has become rather fashionable.

Have Fun!
Reg
Re: 8350B w/83590A repair advice

 

Thanks Dan. Sounds like a good place to begin. I have an Anritsu VNA ... just need to figure out how to use it for this.

I ran the unit over night and had my SA (4407B) on MAX HOLD as I was concerned about frequency drift. Set on CW, 4.5 GHz, 0 dBm:


If I am reading the specs correctly (stability) 250 kHz seems high. I can see the drift in real time but it's quite slow.

Mark
Re: 8350B w/83590A repair advice

 

On Mon, 16 Dec 2019, victor.silva via Groups.Io wrote:

Tried to send direct without looking at the header so it bounced... Sorry
for posting to the list but it won't go otherwise. Here is the original
message:

=== Cut ===
It looks like Paul Bicknell asked for that one first but if he didn't buy it
you can get it. I took some pictures minutes ago, they are available at



It is a 44+ MBytes archive with several photos.
=== Cut ===

Sergey,

I would be interested in the 83570A.

I agree with your recommendation for removing the battery.? I did that to
mine 8 years ago and have not regretted it.

--Victor
---
*
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
*
Re: Help to repair my HP654A Test Oscillator

Bob Albert
 

Maybe mine needs a similar fix.? I will look at it one of these days.? Low distortion is important.

Bob

On Monday, December 16, 2019, 02:34:28 PM PST, Marco Marchesi <marco.marchesi@...> wrote:


Hi. GOT IT!
There was a ground loop gathering noise and hum.?
I moved the ground connection of the third gang of the variabile Cap in the same point where Wien bridge resistive leg is grounded.
Now I got -50,1 dB THD @ 1 KHz, -10 dB under spec.
I'm really happy.
Thank you!

Re: Help to repair my HP654A Test Oscillator

 

Hi. GOT IT!
There was a ground loop gathering noise and hum.?
I moved the ground connection of the third gang of the variabile Cap in the same point where Wien bridge resistive leg is grounded.
Now I got -50,1 dB THD @ 1 KHz, -10 dB under spec.
I'm really happy.
Thank you!
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