Re: HP8753 VNA step attenuator model and replacement
Forgot to say that the SC is 15V with a flat connector. If the 8753E attenuator has 15V coils without contacts it my be a drop in replacement.
Robert G8RPI.
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Re: HP8753 VNA step attenuator model and replacement
Also be aware that the 33321SC and similar attenuators removed from cell phone test sets ?while rated for 4GHz generally work fine at higher frequencies, The coil drive is different (no switches) but if nothing else they are a source of pads.
Robert G8RPI.
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Re: HP8753 VNA step attenuator model and replacement
Hello everyone,
Thanks for all the great suggestions for repair. I failed to mention I have done such a repair before. The document is also very helpful as are some more Youtube videos. However, I was trying to determine if a 33321H or similar would also be sufficient, sometimes they are up for grabs and a pad replacement requires another pad.
From some eBay listings it seems the "Q" stands for DC-8GHz, which means that a 18GHz device should be good (and generally much cheaper than the 'Q' models on eBay).
But first I will take it out and test the pads and open it up.
Thanks again,
Job
PH4AS
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Re: HP8753 VNA step attenuator model and replacement
If this attenuator is anything like typical ones used in that vintage HP gear, then chances are it can readily be fixed. The common problems are bad contacts from wear, grime, and oxidation, and deterioration of the tiny o-rings that hold the contact push rod assemblies. There are many repair instructions online. In a VNA, it's unlikely that a pad card is blown from excessive RF power or DC, unless it was used for power amplifier testing, or experimentally, where high DC could inadvertently be applied. In passive component testing, the VNA's output power should be incapable of damaging the receiving end.
The usual repairs include opening it up (easy once you know how) and inspection, then possibly replacement of o-rings, and contact cleaning and treatment such as with Deoxit.
Ed
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Re: HP8753 VNA step attenuator model and replacement
Hi Job,
You might also look into having the unit rebuilt (if you have a blown pad). I use a place in the USA. They do great work and usually cheaper than buying one. ($400 USD)
Mark
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FS: sets of NOS concentric control knobs
Brad Thompson via
Groups.Io wrote on 12/6/2019 10:29 A
Hello--
I'm offering FS sets of NOS concentric control knobs. These have
longitudinally-grooved
surfaces and black cursor markings which contrast nicely with the
aluminum knob material.
The top knob has a black insert.? Each knob gets secured to its control
shaft by two
.050-inch hex setscrews. A .jpg-format photo is available on
request.
Bottom knob: 0.625 inches in diameter, 0.56 inches high, 0.25 inch
through hole
Top knob: 0.425 inches in diameter, 0.56 inches high, 0.125 inch
blind hole.
(Please note that the knobs are made from aluminum, a conductive metal,
and hence will pose a shock hazard if
you're accustomed to the bad practice
of floating the
ungrounded chassis of an instrument.)
Each set comprises three top/bottom pairs and as a bonus while
the supply lasts, four skirted plastic
knobs with 0.125-inch
brass-insert blind hole and one
0.050-inch setscrew.
I'm asking $10.00 per package? (four two-piece knobsets), which includes
USPS first-class mail to U.S.
locations.
Questions welcomed, PayPal honored.
Thanks, and 73--
Brad? AA1IP
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Re: HP8753 VNA step attenuator model and replacement
Hello Job,
If you end up having to repair that attenuator you may want to watch this youtube video produced by Shariar at thesignalpath.com.? He was troubleshooting an E4433B signal generator earlier this year and diagnosed a bad step attenuator.? Because it's not easy to obtain a replacement he went about repairing the attenuator and presented the process in very good detail.? The process doesn't look too difficult, albeit delicate.
The attenuator segment starts at 11:00.? ?
BTW, the part number for his attenuator is 33322-60014.? Very close to your p/n so perhaps they are mechanically similar.
Hope this helps!
73..... Frank / WA3NHK
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Re: How difficult is it to find or source replacement cables for the HP 4195A?
On December 18, 2019 6:33:28 PM ian.p.brown@... wrote: Thanks for the offer Dave. Hopefully my offer will be accepted. Good luck! -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: How difficult is it to find or source replacement cables for the HP 4195A?
Thanks for the offer Dave. Hopefully my offer will be accepted.
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Re: How difficult is it to find or source replacement cables for the HP 4195A?
On 12/18/19 6:18 PM, ian.p.brown@... wrote: I am considering purchasing a used HP 4195A network spectrum analyzer
that has both the display and measurement units but is missing the
cables to connect them. How difficult is it to source or find cables to
connect them? Is there anything unique about the cables? Any idea how
much replacement cables would cost? It's not tough at all. You'll need one cable with 50-pin AMP Champ series connectors (what people who don't bother to learn call "centronics" or "SCSI" connectors), and if memory serves a DE9 cable, I don't recall the gender but that should be easy to figure out. 50-pin AMP Champ cables have been commonly used in telephony for decades, and are known there as "25-pair" cables. They are easy to find and not terribly expensive; I think I paid about $15 for a two-foot one, new, on eBay. The DE9 cables are commonly available via eBay or Amazon, cheap. If you end up pulling the trigger on it, I can help you with the specifics when the time comes. I can tell you that I very much love the 4195A, it's a fine and very capable instrument. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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How difficult is it to find or source replacement cables for the HP 4195A?
I am considering purchasing a used HP 4195A network spectrum analyzer that has both the display and measurement units but is missing the cables to connect them. How difficult is it to source or find cables to connect them? Is there anything unique about the cables? Any idea how much replacement cables would cost?
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HP8753 VNA step attenuator model and replacement
Hello all,
Just joined the list as I have a HP8753E to repair. It seems the step attenuator in the Source is faulty in the higher regions (region 4 and lower, attenuation above -40 dBm).
While searching around (https://literature.cdn.keysight.com/litweb/pdf/08753-90499.pdf?id=1000000125-1:epsg:man) and inspecting the Source module I found it is a 70 dB 33321Q attenuator.
Does anyone know what the "Q" model means?
The references I know for the 33321 are in but it does not mention Q.
Is it a difference in the connector cable?
Any help appreciated (also on the effects of replacing such an attenuator).
Best regards,
Job
PH4AS
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Re: HP8753D Test 53 Sampler Magnitude and Phase Correction Constants fails
Ok,
here comes the? "A7 Pulse Generator Check"-part. The spectrum analyzer screen dump looks like the service manual, picture A7_comb. I do not have the equipment to verify the comb pattern in the 3.2-6GHz interval. So next step was too look at a comb tooth at 3GHz A7->A4, well it's there but not stable. See pictures A7_A4_comb_tooth.
So I looked at the 45MHz CW signal at the A14<->A7 cable and it looks fine, see A7_A14_45MHz. And I also did the "Rechecking the A13/A14 Fractional-N. Also looks fine, see A7_A14_60MHz.
Not sure what the conclusion is here. I have a "Check the A and B inputs" test with steeper sloping curve and a A7->A4 comb tooth that's not stable at 3GHz, and perhaps a 4MHz reference clock with too low swing.
What kind of measurements would suffer from having the test 53? Sampler Magnitude and Phase Correction Constants properly setup?
I've done some test measurements and the phase seems stable.
Or is a faulty A7 Pulse generator the issue here?
Br
Marcus
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HP8753D Test 53 Sampler Magnitude and Phase Correction Constants fails
Hi all, this is kind of a continuation of the thread I started with EPROM upgrade and corrupt EEPROM issues. First parts of this post is also a copy from my at the Keysights forum, unfortunately without responses so far. Since I lost my EEPROM content I started running the adjustments routines on my HP8753D with 6GHz option.
I have test 44 (Source Default Correction Constants), 45 (Source Pretune Default), 46(Analog Bus), 48(Source Pretune), 52(ADC offset), 47(RF Output Power), 51(IF Amplifier), and 54(Cavity Oscillator Frequency) running successfully. Also tests 21/22 (Operators Check Port 1/2) works fine.
?But test 53 fails quite in less than 30 seconds, it says LO 30MHz on screen a while and then it disappears and I get the fail message. So I have tried to do the Poke commands correction and rerun the tests, still fails at the same place. I have also spied on the GPIB traffic and did not find anything out of the ordinary. However I'm not able to log any low level signalling, my NI card is not advanced enough for that.
Not sure if the "TR3LG" part is whats next in the test sequence or its a part of the failure routine. And when the test stops port 1 outputs a -3dBm 48MHz signal.
GPIB traffic
---------------
?AETR0RAKB100ENFM0ENLNAPTR1+71.100E-06
AETR0RAKB100ENFM0ENLNAPTR1+70.900E-06
AETR0RAKB100ENFM0ENLNAPTR1+66.800E-06
AETR0RAKB100ENFM0ENLNAPTR1+67.000E-06
AETR0RAKB100ENFM0ENLNAPTR1+66.800E-06
AETR0RAKB100ENFM0ENLNAPTR1+66.400E-06
?AETR0RAKB100ENFM0ENLNAPTR1+0.4860E-03
AETR0RAKB100ENFM0ENLNAPTR1+0.4850E-03
AETR0RAKB100ENFM0ENLNAPTR1+0.4850E-03
AETR0RAKB100ENFM0ENLNAPTR1+0.4850E-03
AETR0RAKB100ENFM0ENLNAPTR1+0.4850E-03
?TR3LG
So I started go thru the fault searching schemes in the service manuals. First test was the "Check the A and B inputs" and the look on the sloping curve looks like the good picture but I get a 2dB scale instead so it starts at around 3dB and slopes down to -4dB compared to the service manual picture that shows 1.5dB down to around -2dB.
So that got me running test 18 (ADC offset) 17 (ADC linearity), and then? A12 reference check, A13/A14 Fractional-N all successful.
Then I did the "Check the 4MHz REF signal"-test, the A12 Reference board "resembles" of the service manual, not exactly the same shape and swing. This might be due to my probe setup with 10cm clamps, 1m banana cables, and then a short coax to the scope. See pictures named 4MHz_A12_TP9.
Should I be worried about the differences?
Next test I performed was the "A14 VCO Range Check with Oscilloscope". The look correct, see pictures 10, 25 and 60MHz.
So next up is the? "A7 Pulse Generator Check" but that is for the next post, coming soon.
?
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Re: HP 8920A and 8920B Keypads Identical?
8920a and 8920b front panels are the same except for the label which says 8920b
applies to the 8921 as weil
there is a difference around the slot for the PCMCIA card but electrically the same.
Label on the RF I/O may vary with the power input options
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Re: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter
Hello, finish scanning them in peace, please. We just took in another 55 litres of drink, the bedroom is flooded again. I left a few pages at home at the time, to save shipping fees when sending from Slovakia. These pages are in the new office in Hungary, and I can photograph or scan them as they were small. Tam
With best regards Tam HANNA (emailing on a BlackBerry PRIV) Enjoy electronics? Join 14k other followers by visiting the Crazy Electronics Lab at Am 18. Dezember 2019 20:47:14 MEZ schrieb ArtekManuals <manuals@...>:
toggle quoted message
Show quoted text
I was looking at that again last night as a matter of fact send me you
mailing address again where you want it mailed . I will also send what I
have scanned even though it is missing pages
Dave
On 12/18/2019 12:56 PM, Tam Hanna wrote:
Hello Dave,
sorry to post this publicly, but I really need this resolved.
Do you have any news re the Systron Donner manual I sent more than a
year ago. My wife wants to finally start repairing them...
Tam
- - - - -
With best regards
Tam HANNA
Enjoy electronics? Join 13500 followers by visiting the Crazy
Electronics Lab at
On 18.12.19 15:26, 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
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
Groups.io Links: You receive all messages sent to this group.
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Mute This Topic: /mt/68796741/102401
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Unsubscribe: /g/HP-Agilent-Keysight-equipment/leave/defanged [tamhan@...]
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Re: OCR Pitfalls [was} Re: [HP-Agilent-Keysight-equipment] 2401C Integrating Digital Voltmeter and 2410B AC - Ohms Converter
I was looking at that again last night as a matter of fact send me you mailing address again where you want it mailed . I will also send what I have scanned even though it is missing pages
Dave
toggle quoted message
Show quoted text
On 12/18/2019 12:56 PM, Tam Hanna wrote: Hello Dave,
sorry to post this publicly, but I really need this resolved.
Do you have any news re the Systron Donner manual I sent more than a year ago. My wife wants to finally start repairing them...
Tam
- - - - -
With best regards
Tam HANNA
Enjoy electronics? Join 13500 followers by visiting the Crazy Electronics Lab at
On 18.12.19 15:26, 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
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
Hello Dave,
sorry to post this publicly, but I really need this resolved.
Do you have any news re the Systron Donner manual I sent more than a year ago. My wife wants to finally start repairing them...
Tam
- - - - -
With best regards
Tam HANNA
Enjoy electronics? Join 13500 followers by visiting the Crazy Electronics Lab at
toggle quoted message
Show quoted text
On 18.12.19 15:26, 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
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.
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Re: Wanted: HP 3458a DVM in non-working condition
I¡¯ve read that in some metrics, an HP3456A is slightly superior to the 3457A in practice, even if the 3457A might be a little nicer on paper. This isn¡¯t limited to the much improved LED display; the 3456A is slightly more stable than the 3457A if I recall correctly.
Unfortunately, the 3456A can¡¯t be digitally calibrated; you still need to adjust potentiometers.
With regards to the bean counter, he/she is probably the same one that struck the backlight off of my 3468A, in addition to a few other details that are inferior to my one digit less precise 3466A, like AC RMS accuracy and battery life. Sincerely, Dennis Chertkovsky
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Show quoted text
On Dec 18, 2019, at 9:32 AM, Kevin Oconnor < kjo@...> wrote: 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
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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
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Dave McGuire
