Whats the value of a (defective?) HP 54845A 1.5Ghz scope? - Page 1
Forum section: electronics / testgear

author: osch
author_rank: Newbie
timestamp: July 06, 2015, 05:17:16 pm
content: I found this scope advertised locally. It's listed for 1200 USD.It boots and shows display, but fails on self test (and calibration?)Probes are not included. What do you think this is actually worth, and is it even worth buyingwith the errors?

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 06, 2015, 05:44:38 pm
content: Quote from: osch on July 06, 2015, 05:17:16 pmThat depends entirely what it is worth to you, and if you have access to cheap spares to fix it. This looks like one of the first generation Infiniium scopes (HP's/Agilent's Windows scopes) which ran Windows 95 and later Windows98, and especially the Windows95 models weren't exactly great scopes.The 54845A offers 1.5GHz bandwidth and 8GSa/s sample rate (2ch mode, 4GSa/s in 4ch mode) which isn't bad, however the sample memory is ridiculously small (64k), and the max waveform update rate a paltry 2100 wfms/sec. The architecture of these scopes is pretty slow, probably caused by the crude design (i.e. two graphics cards). It took quite some time until Agilent managed to do a Windows scope right.$1200 is definitely too much for it, especially when there are no probes included and considering that this is a first gen model (HP) and not the later Agilent labelled variant, my guess would be below $600 is more appropriate. But again, unless you have access to cheap spares I'd rather use the money and buy something else as even if you manage to fix it you'll still end up with a scope that performs poorly for most tasks.

author: rsjsouza
author_rank: Super Contributor
timestamp: July 06, 2015, 06:13:37 pm
content: Finding value on a defective instrument without an available service manual is daunting. As Wuesterschund mentioned, this generation is the oldest of the family and has very limited specifications of memory depth and waveform update rate. Also, keep in mind you could be investing $1200 on other models with much better specifications but not the same bandwidth and sample rate.From about the same era I would thinkthis LeCroy LC574ALfor less than half the price is a better choice - even aservice manualis available.For higher prices there is also aLeCroy LT364Lor aTDS784Dwhich seem quite decent (although I am not sure about the TDS784's memory). Both have service manuals.Recently I was searching for several oscilloscopes and found some of the HP/Agilent 54815/825/845 that seemed to be showing only some minor issues, but the sheer amount of money asked by the sellers scared me away. For this kind of price, my reasonably priced options on the HP/Agilent brand fell on the two-channel DSOX2000 series (one ishere).

author: osch
author_rank: Newbie
timestamp: July 06, 2015, 06:30:54 pm
content: Thanks for the input. I have no previous experience with scopes, and not much repair experience either..I think i will invest in something newer instead

author: miguelvp
author_rank: Super Contributor
timestamp: July 06, 2015, 06:37:21 pm
content: A search for hp 54845a timebase fail shows someone having the same problem back in 2010 after trying a full year to get it working he started to ask, seems no resolution was achieved.https://www.google.com/search?q=hp+54845a+timebase+fail&oq=hp+54845a+timebase+failProbably the same scope?That said, here is a link of someone fixing one:http://www.dasarodesigns.com/projects/fixing-an-hp-agilent-54845a-infinium-oscilloscope/Myself, I wouldn't take a $1200 gamble, but I don't need a 1.5GHz scopeEdit: In part because buying 1.5GHz probes might be more than the scope

author: osch
author_rank: Newbie
timestamp: July 06, 2015, 06:40:37 pm
content: Quote from: miguelvp on July 06, 2015, 06:37:21 pmYeah i saw those.. did not give me any more hope of fixing this. I don't really need a 1.5GHz scope either, but after seeing ebay prices on some of these i figured it could be a good buy.

author: Muxr
author_rank: Super Contributor
timestamp: July 06, 2015, 06:48:51 pm
content: Quote from: osch on July 06, 2015, 06:30:54 pmThese high bandwidth scopes aren't really well suited to be a day to day scope or a beginner scope. Higher bandwidth means more noise and the inputs are 5V max I believe. They also take forever to boot and tend to use a lot of power, which means they have high airflow cooling, so a lot of noise is to be expected. You really want a general purpose 70-100Mhz 1-2Gs/s scope as your first scope.

author: nctnico
author_rank: Super Contributor
timestamp: July 06, 2015, 07:16:19 pm
content: Quote from one of the links:plus countless hours of my time, but, oh well, it was fun!Defective equipment can be fun and a good exercise to repair but it takes time and effort.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 06, 2015, 07:51:41 pm
content: Quote from: osch on July 06, 2015, 06:40:37 pmDon't get fooled by the often ridiculous asking prices on ebay, what matters is what these things actually sell for.Quote from: Muxr on July 06, 2015, 06:48:51 pmI have to disagree slightly as this depends on the scope. For example, my private day to day scope is a LeCroy WavePro 7300A 3GHz scope, although with 48Mpts sample memory and approx 250k wfms/s it's not nearly as bad as this HP. Noise isn't a problem, even less so with the 200MHz bandwidth limiter engaged, and the inputs are 50ohms/1Mohms switchable as any other scope.It's still quite huge and not as silent as say a Rigol, though, but compensates that with the very advanced functionality

author: free_electron
author_rank: Super Contributor
timestamp: July 06, 2015, 09:44:46 pm
content: timebase failure ... that's one of the main asic's that is out. forget it. i have spareparts for the 81x 82x but not for the 84x series.the 845 is a totally different beast from the 81x or 82x (81x and 82x are essentially the same board except for R147 ...)the 845 has different fiso's and a different frontend.this machine is worthless.

author: Stray Electron
author_rank: Super Contributor
timestamp: July 06, 2015, 10:10:36 pm
content: Free Electron is right, it's worthless. The seller is insane if he thinks that it's worth $1200! Even if it worked, it's not worth that IMO. I doubt that HP even carries parts for that model any longer but even if they did, it would cost more than the scope would be worth. MANY of the newish HP and Tektronixs use custom ASICs and those are virtually impossible find except from the manufacturer. Even if you could fix it, most of this type of test equipment is electronically calibrated and you need a small mountain of precision Standards to calibrate them.You should be able to buy a GOOD fully working scope for far less than $1200. I have several used 1 GHz Lecroy scopes and only one cost $200, the others even less. And for well under $100 each I was able to add FULL memory and ALL of the SW options to them.MOST used scopes will come without probes and some use very special and very expensive probes so you always need to check on that before buying any scope. I've been able to buy the correct LeCroy probes on Ebay for about $50 each.

author: rsjsouza
author_rank: Super Contributor
timestamp: July 07, 2015, 12:45:07 am
content: Quote from: Stray Electron on July 06, 2015, 10:10:36 pmAnd yet there are several eBay sellers that jack the price at almost $4k USD. What's in a name, one would guess...

author: miguelvp
author_rank: Super Contributor
timestamp: July 07, 2015, 01:15:38 am
content: $4K ones are fully working ones with probes. If you need 1.5 GHz bandwidth it seems like a good price (unless it breaks in a couple of months or during transport)

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: July 07, 2015, 01:32:27 am
content: 10$ for the Type M keyboard. At least I think that's what it is.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 07, 2015, 05:07:47 am
content: Quote from: rsjsouza on July 07, 2015, 12:45:07 amJust because some sellers *want* $4k for it doesn't mean they get it. At the end of the day what counts is the price an item sells, and in terms of these HP scopes that's rarely anywhere close to $4k.Quote from: miguelvp on July 07, 2015, 01:15:38 amI don't think $4k is a good price for such a poor scope, even with probes. For example, I paid close to $5k for my LeCroy WavePro 7300A, but that's a 3GHz scope with 20GSa/s, 48M memory, 250k waveforms, all software options enabled, and this one was made in 2008 and is fully supported by its manufacturer (Agilent stopped support for these Infiniium scopes many years ago already). You can also often find the predecessor WavePro 960 (2GHz 16GSa/s) which is from the same time as this HP scope for less than $2500, and this is a vastly more capable scope than the HP.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 07, 2015, 05:18:42 am
content: Quote from: Alex Eisenhut on July 07, 2015, 01:32:27 amThat's an old Dell keyboard that came with PCs like the Dell Optiplex GX100 (PentiumII/III desktops), not a Type M.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 07, 2015, 08:54:39 am
content: Quote from: Alex Eisenhut on July 07, 2015, 01:32:27 amIf that would be an original IBM Type M keyboard, it would be worth at least $ 100 in good condition.

author: Fungus
author_rank: Super Contributor
timestamp: July 07, 2015, 09:06:24 am
content: Quote from: osch on July 06, 2015, 05:17:16 pmAssuming it can be made to work:a) Find out how much you're going to have to spend on probes to get access to that 1.5GHz - it might interest you.b) Take a long hard look at what you can buy new with $1200. It will have less bandwidth but a *lot* more features.Or .... if you don't need insane bandwidth you could go for the people's favorite DS1054Z and still have enough left for a decent bench power supply, signal generator + a nice soldering iron.Your choice.

author: Fungus
author_rank: Super Contributor
timestamp: July 07, 2015, 09:14:15 am
content: Quote from: HighVoltage on July 07, 2015, 08:54:39 amIt isn't, it's a Dell.(Mightbe clicky...but not a real Model M).

author: EEVblog
author_rank: Unknown
timestamp: July 07, 2015, 11:21:08 am
content: Quote from: osch on July 06, 2015, 06:30:54 pmWise.These scopes can offer exception bang-per-buck for high bandwidth work, but are otherwise useless for everyday use. They are huge, heavy, loud, slow, horrible UI etc.

author: free_electron
author_rank: Super Contributor
timestamp: July 07, 2015, 01:38:11 pm
content: Quote from: EEVblog on July 07, 2015, 11:21:08 amtrueQuotenot really. not more than a lecroy or tek of same vintageQuotenope. whisper quietQuotenot really. they respond to user operation much faster than teks or lecroy of same vintage. they behave as quick as an analog scope . i;d say they rect even faster than more modern hp like the 6000 / 7000 series. i find my 7104 notably slower in button/knob response than the infiniiums. and i'm not talking screen refresh. simply pressing a button and see the scope pop up the menu or react. spinning the timebase is instant reaction , same for verticalQuotesame ui still in use on infiniiums today.

author: -jeffB
author_rank: Regular Contributor
timestamp: July 07, 2015, 02:14:14 pm
content: Quote from: Wuerstchenhund on July 06, 2015, 07:51:41 pmIndeed.This may be a bit off-topic for a Test Equipment forum, but it's good to know how to findactual sale priceson eBay.First: When you search for an item on eBay, the results will show items currently for sale. Some will be Buy It Now listings; these prices may be high, and there's no guarantee that anyone will buy at that price. Some will be auctions with a high opening bid; same thing. Some will be auctions with alowopening bid; until the auction closes, you can't tell what the actual sale price will be.To see actual sale prices, look in the left-hand margin of the search results page. There's aCategoriessection, then a bunch of other sections for refining your search. Near the bottom of the controls, there's a section titledShow only. Under that section, there's one box forCompleted listings, and another forSold listings. This last one is what you want. (It's only appeared in the last couple of years; prior to that, you could only select Active or Completed listings, and Completed listings showed items that didn't sell as well as those that did.)Second: Even if you're looking atSold listings, some of the prices may have a line through them, indicating that the seller accepted a Best Offer price lower than the Buy It Now asking price. eBay used to display the actual accepted price, but they stopped doing that. So, a struck-through price is only a ceiling; you know that the actual price paid was lower.Fortunately, there's a tool that lets you look up the actual accepted Best Offer price! It's here:http://www.watchcount.com/#serpGo to this page, enter the auction number, and you'll see the actual accepted price, and/or a link to see the actual accepted price on eBay. (These eBay links often go to a non-US eBay site. If you're using eBay outside the US, perhaps yourSold listingswill already show the actual accepted price.)So, for HP 54845A, I see these results:http://www.ebay.com/itm/HEWLETT-PACKARD-INFINIUM-4-CHANNEL-OSCILLOSCOPE-1-5GHZ-8GSa-s-MN-54845A-/121652506910-- asking price US$1199, sold for US$1000, channel 1 and 2 failed self-calibrationhttp://www.ebay.com/itm/HP-Agilent-54845A-Infiniium-Digital-4-Channel-1-5GHz-8GSa-s-Oscilloscope-/161690698849-- asking price US$1850, sold for US$1325 + US$100 shipping, gives "Fine Interpolator handshake failed: service is required" errorhttp://www.ebay.com/itm/HP-AGILENT-INFINIUM-54845A-1-5GHz-4-CHANNEL-DIGITAL-OSCILLOSCOPE-DSO-/281679430391-- sold for US$1551 + US$78 shipping, completely passes self test and self calhttp://www.ebay.com/itm/HP-Agilent-54845A-Infiniium-Digital-4-Channel-1-5GHz-8GSa-s-Oscilloscope-READ-/321741445290-- asking price US$999.95, sold for US$700 + US$51.38 shipping, can't boot/software not installed, one channel module marked "Bad"This makes it look unlikely that you'd be able to flip a $1200 non-working example for a profit on eBay.

author: Fungus
author_rank: Super Contributor
timestamp: July 07, 2015, 02:15:23 pm
content: Quote from: free_electron on July 07, 2015, 01:38:11 pmNew ones are still horrible?

author: rsjsouza
author_rank: Super Contributor
timestamp: July 07, 2015, 03:16:06 pm
content: Quote from: Wuerstchenhund on July 07, 2015, 05:07:47 amJust to clarify, I didn't mean theysellfor these ridiculous prices... Just that people have the indecency to offer them at these prices. -jeffB's post is a good reference on how to find the actual value.Quote from: miguelvp on July 07, 2015, 01:15:38 amNot really; in my search only one of the postings had probes. All others were just working, functional, 90-day warranty, NIST-calibrated, etc.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 07, 2015, 03:20:22 pm
content: Quote from: -jeffB on July 07, 2015, 02:14:14 pmI did not know about that ebay tool.Thank you.Everything else you said is right on from my perspective.An I have bought lots of test gear on ebay, mostly Germany but also US and rest of the world.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 07, 2015, 04:06:58 pm
content: Quote from: Fungus on July 07, 2015, 02:15:23 pmNot that bad as the UI on these 54800 Series Infiniiums but it's still very obvious where the UI comes from and that it was designed for mouse control and not touch.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 07, 2015, 04:22:58 pm
content: Quote from: free_electron on July 07, 2015, 01:38:11 pmNot really. Maybe the low bandwidth models are different but back in the days I had to work with Agilent 54846A/B scopes, and while they're not as noisy as say a LeCroy WavePro 7k, they are far from being quiet, and roughly on par with a LeCroy WavePro 950.QuoteI disagree. The old Infiniiums react pretty quick to user input, but so does any other comparable scope (i.e. the LeCroy WavePro 900/7k Series). But as soon as you try to do something more challenging (i.e. complex math) then the Infiniiums get pretty sluggish pretty fast, thanks to its awfully slow architecture, and especially the first models running Windows 95 were pretty prone to crash.HP/Agilent made quite a few good scopes over the years, however these Infiniiums certainly aren't great examples of that. They wanted to be the first one who offered a Windows-based scope but the actual result was pretty poor, even by those days' standards.

author: Hydrawerk
author_rank: Super Contributor
timestamp: July 07, 2015, 07:47:12 pm
content: HP 54845A is at least 16 years old, because HP renamed to Agilent in 1999.