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Re: 8340A Fault - ADC
From googling, hp crosref (link??), and bitsavers. Might have to Ctrl + F part of the name like I did for "DC856" since pdf file have a hard time reading.
Signetics Corp. NE5018F - page 550 Datel Systems Inc. or Datel-Intersil ADC856C - page 145 Micro Power Systems (owned by the Exar Corporation) MP7533MP - page ??? ??? need to find this. I thought the Datel one with the custom HP number would be hard. and one more, the MUX Precision Monolithic Inc. - page 764 These are a fountain of knowledge. Now only specs but app notes and introductions as to why to use them in design. Enjoy. -Lex |
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Re: HP 8341A sucessfully FIXED!
You did a great job Tobias. Don't sweat on it breaking. As long as you've documented everything, I'm confident it can be fixed with no problem. It was a really lucky fault though. Had something on the hybrid circuit blown.... that wouldn't have been so good.
As for the calibration software, Tony's one drive is great. If you want, there is the raw file in this group as well. I wonder what the path to failure was? You had a blown relay, a bad YTO driver, and of course that shorted feed thru capacitor. The cap was shorted in the first place before you put 1.5 Amps thru it. Heres my theory: ??? on the power supply section surged? > breaks relay but goes to YTO driver > components break on the YTO driver > something on the YTO driver causes that feed thru on the YTO to become shorted. How other components were not affected will be a mystery. Maybe they were? It can be called case closed if you can find the original fault and its pathway. Till then this is good enough. -Lex PS: I can explain what happened when that feed thru cap became 20Kohms before it became a 1 ohm short again. Normally in the AC condition, any incidental AC signal (probably from either the YTO driver or the YTO itself is suppose to pass thru to grounded case from the coil via the feed thru cap which acts as a short for AC. In the DC condition the cap is an open circuit and instead heads to the YTO driver via the wire connection. However since you put high power thru the cap the first time, it turned into a 20Kohm resistor. What this ended up doing was fixing the short to ground for DC but now you have both the DC and some AC signals mixed together going thru the wire of the -40V supply, the coil (has less impedance than 20Kohms), and the YTO driver. That is why you saw the unstable results with the YTO loop. Anyways, that feed thru cap had to be replaced one way or the other since there needs to be a short to ground case for AC but not for DC. DC goes thru the wire. |
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Re: OT Omni Spectra Semi-Rigid Tools
Jim:
I came across a 1990 M/A-Com catalog that has quite a bit of tooling in it. I tracks what you found as well.? I'm putting together a spread sheet of all the kits and numbers....Can send along to whoever wants.... Dan in Chandler, AZ Thanks so much for looking around on this! |
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Re: 8340A Fault - ADC
Hello Calvin,
I see. Sorry about the mix up. Just want to make sure. The basic tests are [Shift + Free run], [Shift + Manual] (done), and [Shift + M4]. [Shift + Free run]?is for the lighting and is to make sure all LEDs light up like Christmas. It also indirectly tests the processing side by noting that the correct behavior of the marching pattern as described in the manual. You've pressed [Shift + Manual]?for the fault annuciator already so we know to focus on the ADC. As for [Shift + M4], I don't think it'll be of any help but you can try. Actually I forget what it will do with an ADC fault. Its a diagnostic test that tests everything and will list everything. The thing to note here is that an ADC is higher in the chain vs individual components tethered to sections of the rf path. The Processing section being the highest in the chain. You're right that 8340B schematic is literally broken and 8340A (assuming this since they don't have a 8341A) is unreadable but did you try all of the manuals? 8340A 8341A 8340B and 8341B are all the same except for FM input, SYTM for 20GHz vs 26.5GHz, and a sweep output 5 vs 10 V/GHz. I do admit it is still hard to read but I've seen harder. 8673B + 8673C/D service manuals were insane before I found a recent independent scan via google search and this group. Here is a link for 8341B component level volume. (page 201) ? Be sure to read up on theory of operation for A27 in the assembly level volume as well. A21 is involved based on the RF block diagram. What its doing and how it affects A27 that would have to be read. I see "ADC timing" as the name of the signal between those boards. If worse comes to worse there is google and bitsavers for individual component catalog/product guide searches (ie. motorola, nec, pmi, national semiconductor).??or ebay at the assembly level. So far it looks good in terms of economical repair. Anything encased in a solid block of metal that is damaged on the RF path is expensive. Can still be repairable within economical means as shown by Tobias' recent post. That was really lucky though imo. If the damage was on a hybrid circuit (ie bond wire or MMIC amp, transistor, diode)..... uneconomically repairable. It can still be repaired but you'd need to be in the business of wire bonding and Microwave IC design or negotiate the replacement assembly's the price down. Prices can be negotiated down if you know if the component is used in another instrument. HP usually repurposes the same components in different equipment. An example is a hybrid circuit I thought I was doomed to be unobtainium. Turns out this circuit is used in 3 instruments. What would have been a $600 - $1500 part was negotiated down to $175. Probably lower with the way things are trending. Checking now, there is a seller selling more than 10 but doesn't know what they have. There is another seller also selling extra components along with the component of interest for half of what the lone assembly would go for. Anyways I don't believe you will have this problem or those types of hoops and hurdles. I suspect a few components on a board assembly or 2 is the issue that failed due to old age. ICs or capacitors that age with heat, cycle use, and naturally occurring chemistry (oxides and acids forming). Compare that to someone that put in too strong of a signal and blew the inputs of the AM and PM. Worse would be the RF output (that attenuator and other RF modules are not cheap) or a physical drop of the instrument or on top of the instrument due to moving. Good luck with your potential buy. -Lex |
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Re: 8340A Fault - ADC
Rapes and Stinks, no?
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Now all we need is someone to undig the datasheet. The moment we have that, we can slink something together with ease. I dont want to promise anything as my life currently is a bit topsy turvy and I am already caught up in projects...but if you need help, I am willing to take a look at the Design and help out. If you cant solder SMD, I might be able to help too. --- With best regards Tam HANNA (emailing on a BlackBerry PRIV) Enjoy electronics? Join 6500 other followers by visiting the Crazy Electronics Lab at Am 23. Oktober 2017 08:34:59 MESZ schrieb "Tobias Pluess tobias.pluess@... [hp_agilent_equipment]" : ? |
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Re: 8340A Fault - ADC
开云体育The ADC is in a wide DIP (don't know the dimensions from heart, but it has the same width as an ordinary EPROM).-------- Original message --------
From: "Tam Hanna tamhan@... [hp_agilent_equipment]"
Date: 10/23/17 07:52 (GMT+01:00)
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] Re: 8340A Fault - ADC
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I also googled but a minute or two.
What is the housing of that ADC IS? Worst case, one can IMHO grab an SMD part and make a fourlayer adapter at the usual PCB making suspects On 23.10.2017 07:13, Tobias Pluess
tobias.pluess@... [hp_agilent_equipment] wrote:
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Re: 8340A Fault - ADC
开云体育I also googled but a minute or two.
What is the housing of that ADC IS? Worst case, one can IMHO grab
an SMD part and make a fourlayer adapter at the usual PCB making
suspects On 23.10.2017 07:13, Tobias Pluess
tobias.pluess@... [hp_agilent_equipment] wrote:
??? |
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Re: 8340A Fault - ADC
开云体育Hi CalvinI checked the A27 parts list. Following chips seem to be used:
NE5018F DAC - can be found on eBay
1826-0881 ADC - this is actually an ADC856C. I am unsure whether this can be replaced easily, but I only searched for approx. 5min :-)
MP7533MP - a pin compatible replacement from Maxim is available, called MX7533. Should be available at the usual distributors (Mouser, Digikey, whatever).
Best
Tobias
-------- Original message --------
From: "Calvin Guan guancalvin@... [hp_agilent_equipment]"
Date: 10/23/17 04:39 (GMT+01:00)
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] Re: 8340A Fault - ADC
?
Hi Lex, Yes, it’s ADC fault. The instrument has Fault annunciator lit. I asked the guy to press [shift][manual], and the ADC lights are blinking the the Entry Display. The other faults that would turn on the Fault annunciator are PEAK, TRACK, KICK, and
CAL. Although the PEAK and TRK aren’t not blinking, I don’t know if they are also fault as ADC failure may automatically disable PEAK and TRACK.?
I read the 8340B A27 assembly schematic from keysight. Unfortunately, the ADC Clock control and input MUX part is mostly messed up, but the ADC chip itself seems very simple.The 8341A service manual schematic is not humanly readable.
Good thing about it is there are no other abnormal annunciator are lit. UNLEVELED is off, UNLOCK is off. My gut feels it’s something simple but I could be totally wrong.
If the store owner is nice enough, I *might* be able to visit the him to see the instrument in person. What basic tests would you suggest me to run?
Thanks,
Calvin
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Re: 8340A Fault - ADC
开云体育Hi CalvinI have the complete 8340A service manuals in paper on my desk. I try to find someone who can scan these plus size pages. My scanner at home or in the office can't do that.
Unfortunately, there are no human readable schematics available on the net. I wonder what those guys think when they upload such crappy documents - its absolutely pointless if the schematics are unreadable :-)
Anyway, I can not yet scan the whole thing, but I can make some (readable!) photographs of the A27 schematics if you like.
If you can run another self test on the unit, please do [shift][ext] which shows whether all PLLs are locked. As long as the oven is cold, REF will be flashing, which is okay, it will go away as soon as the oven has reached temperature after about 5min.
The oven annunciator should be off. All other PLLs should be locked. If the YO is unlocked.... well, from my repair project you probably know that one can be lucky and the YO can be repaired, but if the YO is blown it can be messy.
If the unit is not too expensive I would go for it. ADC seems to me like a problem which should be repairable (and even if the YO is blown it would be an interesting project to fit another YO, the original 0586-7323 seems unobtanium... :-)).
I once had a 4195A where a? DAC chip had a crack and thus an internal bond junction went bad, leading to the error that the DAC was working in principle, but one single bit was not working. I hat to replace the DAC, which is still manufactured today, so
it was easy to obtain a replacement. I would not be surprised if the same was true with the ADC you have problems with.
Tobias HB9FSX
-------- Original message --------
From: "Calvin Guan guancalvin@... [hp_agilent_equipment]"
Date: 10/23/17 04:39 (GMT+01:00)
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] Re: 8340A Fault - ADC
?
Hi Lex, Yes, it’s ADC fault. The instrument has Fault annunciator lit. I asked the guy to press [shift][manual], and the ADC lights are blinking the the Entry Display. The other faults that would turn on the Fault annunciator are PEAK, TRACK, KICK, and
CAL. Although the PEAK and TRK aren’t not blinking, I don’t know if they are also fault as ADC failure may automatically disable PEAK and TRACK.?
I read the 8340B A27 assembly schematic from keysight. Unfortunately, the ADC Clock control and input MUX part is mostly messed up, but the ADC chip itself seems very simple.The 8341A service manual schematic is not humanly readable.
Good thing about it is there are no other abnormal annunciator are lit. UNLEVELED is off, UNLOCK is off. My gut feels it’s something simple but I could be totally wrong.
If the store owner is nice enough, I *might* be able to visit the him to see the instrument in person. What basic tests would you suggest me to run?
Thanks,
Calvin
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Re: 8340A Fault - ADC
开云体育Hi Lex,Yes, it’s ADC fault. The instrument has Fault annunciator lit. I asked the guy to press [shift][manual], and the ADC lights are blinking the the Entry Display. The other faults that would turn on the Fault annunciator are PEAK, TRACK, KICK, and CAL. Although the PEAK and TRK aren’t not blinking, I don’t know if they are also fault as ADC failure may automatically disable PEAK and TRACK.? I read the 8340B A27 assembly schematic from keysight. Unfortunately, the ADC Clock control and input MUX part is mostly messed up, but the ADC chip itself seems very simple.The 8341A service manual schematic is not humanly readable. Good thing about it is there are no other abnormal annunciator are lit. UNLEVELED is off, UNLOCK is off. My gut feels it’s something simple but I could be totally wrong. If the store owner is nice enough, I *might* be able to visit the him to see the instrument in person. What basic tests would you suggest me to run? Thanks, Calvin
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Re: 8340A Fault - ADC
Hello,
It depends on who you're buying from. Personally I would go for it if I knew the basic diagnostic self tests were working, the seller isn't selling a physically damaged unit and if I had the money.?I have to ask though. Did you mean ALC? There is no fault light indicator for ADC. Possible scratch or sticker residue??It can be anything from a faulty reference to something as serious as the RF module(s) for the ALC section. I have the manuals but it would be a written essay on here explaining or posting pics of everything in detail. Check all manual paperwork from Keysight. Its all there but everything is imho mislabeled. Search for all 8340/1/A/B models (4 models in total). This also sounds similar but may not be the same problem as another member here had. Link to another faulty unit:? All in all I would need further information obtained from diagnostic tests. Also its ultimately up to you but as I said, I personally would buy it and accept whatever consequences I may receive. -Lex ? |
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Re: 8340A Fault - ADC
Fault could be either the ADC chip or the signals controlling it. I
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believe the 8340 permits direct control of the peripheral boards. Diagnostic procedure would be to measure value at ADC input and look at corresponding digital; values. You could pull eht ADC chip or try to run the board in a home made test jig. Additionally, as I remember, there are some board specific diagnostics that you can invoke. Look over the board schematic and decide how best to attack the problem - probably not the digital control signals as other boards using the same control signals working (?). Hi there, |
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8340A Fault - ADC
Hi there,
I am looking into buying a 8340A with known problem — Fault light on, fault code ADC. From the service manual, it says ADC fault indicates CPU detected ADC circuit problem on A27 level control assembly. When ADC is faulting, SYTM won’t track and won’t peak. However, the manual has very little information on A27 troubleshooting. What would have caused the ADC fault? How does the power-on-self-test determine the ADC circuit is bad? Could it be as simple as bad reference voltage on the ADC or something very involved? Thank you! Calvin |
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Re: HP 5335A counter without fancy options, has HPIB -- fail 2.1 U25 RAM
John
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I could use a parts unit. What sort of compensation do you need? Dennis -------------------------------------------- On Sun, 10/22/17, John Griessen john@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
Subject: [hp_agilent_equipment] HP 5335A counter without fancy options, has HPIB -- fail 2.1 U25 RAM To: hp_agilent_equipment@... Date: Sunday, October 22, 2017, 2:52 PM Anyone want it?? Parts of it?? No oven crystal in there, no 1.2GHz input C. ------------------------------------ Posted by: John Griessen <john@...> ------------------------------------ ------------------------------------ Yahoo Groups Links ? ? (Yahoo! ID required) ? ? hp_agilent_equipment-fullfeatured@... |
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Re: OT Omni Spectra Semi-Rigid Tools
Not mentioned in this catalog, but there are content lists for the individual parts. JimMc
On Sunday, October 22, 2017, 10:35:36 AM PDT, Steve - Home Steve-Krull@... [hp_agilent_equipment] wrote:
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Jim, Any mention of a T-200/500? That’s what I have here. Thanks, Steve WB0DBS On Oct 22, 2017, at 11:42 AM, J Mcvein jmcvein@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
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Re: OT Omni Spectra Semi-Rigid Tools
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On Oct 22, 2017, at 11:42 AM, J Mcvein jmcvein@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
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Re: OT Omni Spectra Semi-Rigid Tools
I have a 1991 OS catalog here, and there is a tooling section.? T-250 is listed as SSMA-(OSSM), T-450A is TNC. T-400 is for Type N. I have never been fortunate enough to find a T-200 in good shape in the surplus wild. JimMC
On Saturday, October 21, 2017, 5:52:30 PM PDT, djn@... [hp_agilent_equipment] wrote:
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Thanks Steve. I also have found the Tyco instruction sheets that show the use of the tooling. They also reference the M/A-Com and Omni-Spectra part numbers for the various tools. However, the T-250A/450A is a mystery still...... Also, they must have made kits for N and TNC, but I find no reference to them... So, I was wondering if Omni-Spectra ever put out tool info in their literature/catalogs... Dan
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1740A Horizontal setup
Hi everyone, I'm restoring a 1740A back to health again and its up and running but some form of calibration is now required.
If I can find out to link photos etc from my Flickr account I could show you these in photo and maybe video formats to give you more of true picture of whats happening then rather hoping that I can describe?it well enough so you can understand what I mean.? Anyone able to offer any assistance with this at all? I have the service manual but it does not make it very clear on how to do these things unless of I'm going blind. Graham |
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Re: HP 8341A sucessfully FIXED!
开云体育Hi Tony wow, cool, thanks. These files should work for the 8341A as well I think. I will give it a try ;-) Since I cannot run HP Basic stuff, I will translate the programs to Python which runs nicely with GPIB cards and USB adaptors. I already did that with the calibration program for the HP 4195A. Thanks Tobias From: hp_agilent_equipment@... [hp_agilent_equipment@...]
Sent: Sunday, October 22, 2017 17:07 To: hp_agilent_equipment@... Subject: Re: [hp_agilent_equipment] HP 8341A sucessfully FIXED! ?
I have the one for the 8340B if that helps.
Original files here:
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Unlocked files here:
I think I may also have put this in the files section of the forum.
TonyG
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