Re: HP 54512B (pair) repair
I've gotten a bit of a chance tonight to check a couple of?things with one of the units:
Unit #2?(S/N: 3214A00704: consecutive units!) - Voltages on rails:
- +11.924V
- +12.050V
- -3.27V (fluctuating somewhat; no significant ripple on it)
- -5.2289V
- 3.5285V
- 5.2067V
- There's a coin battery on the main board, which I didn't remove yet (I'd rather measure its voltage before I do, in case it's still good and holds the memory). It's a Panasonic and I can only read "CR..." from it. Would there potentially be more harm done by removing it, than simply losing the cal constants, in case it's still good for some reason? I'm thinking of biting the bullet and removing it, replacing it, and then seeing where that takes me.?
So this second unit has more issues than just a dead battery (in case the latter checks out). I'll have to remove the power supply module and see what could be wrong with the -12V rail. I'm provisionally blaming the unruly -12V rail for the additional error this second unit has, which the first doesn't. So my money's on that the?first one has a good -12V rail.? Radu.?
On Tue, Feb 25, 2025 at 7:14?AM Radu Bogdan Dicher via <vondicher= [email protected]> wrote: Awesome, thank you, Peter.? I wonder if anyone has a fresh recollection of what battery or maybe battery-backed RAM would be suspect and possibly needed so I'd start working on an order to have the parts ready by the time I carve out some time to open these. From what I know about these generation scopes, replacing the battery is probably a good idea anyway. The cal constants seem to be gone, so nothing to lose there.? I wasn't able to find this information (particularly info on the battery) in the manuals, which I find odd.?
On Tue, Feb 25, 2025 at 5:26?AM Peter Gottlieb via <hpnpilot= [email protected]> wrote: Seems like you are on the right track.? Many HP scopes of that era lose their
minds if the memory battery goes dead.
Peter
On 2/24/2025 11:09 PM, Radu Bogdan Dicher via wrote:
> Hi all,
> Over the weekend I've got a couple of 54512Bs at my desk to seek to bring back
> to full functionality. My main scope is a 54522A, and I assume they have some
> commonalities, but I've yet to open mine (it came to me fully refurbished and
> never needed to open the case). I'm not very familiar with this other series,
> and hope on some good input and recommendations.
> The documentation is not as good as others I've seen from HP. Specifically for
> this unit (54512B), Keysight only seems to have a very skinny (by HP
> standards) Service Manual which can't honestly be called "module-level Service
> Manual," as it doesn't really into much detail on the different modules. Then
> there's a "Front Panel Reference," which is an odd other way of naming what I
> think is the Operating Manual. A couple other manuals have to do with
> programming. That's it.
> Sometimes in a series you have to look for the main unit, but in this case I'm
> not sure that's the 54501A, as the catalog spec sheet seems to suggest, or the
> 54505B, as per the SM. Maybe someone very familiar with the series would know.
> Artek doesn't have manuals for the 54512B at all, but they do for the 54501A,
> and if applicable, I'd get the series of six manuals they sell as a bundle. If
> no go, I'll be a bit in a bind with fixing this given what I have at hand. I
> am aware HP was not longer offering component SMs by this point, though I
> don't know for a fact on this specific series and scope (but I do regarding
> the better?/later? 54522A).
> Is this really capable of FFT to 500MHz, even if the scope is rated to 300MHz?
> I can't make sense of that.
> Now, on to the specific issues with the units.
> *Unit #1 *(S/N: 3214A00705)
>
>? ?* Upon starting it, it reports something like "TRYING TO START REALTIME
>? ? ?CLOCK," which is unsuccessful after a time countdown from I think 60:
>? ? ?"REALTIME CLOCK FAILED TO START - DISABLED."
>? ?* Once I get it to display the default screen and output a trace, it stated
>? ? ?"Default cal loaded. Re-cal instrument."
>? ?* Self Test passes all.
>? ?* I'm also seeing a solid and apparently accurate 5V from the DC Cal output
>? ? ?in the back. I haven't tried the AC Cal output.
>? ?* Note this one had the Cal switch in the back in the UNPROTECTED position
>? ? ?when I got it.
>? ?* I'm able to display the square wave test signal from the front panel.
>
> *Unit #2 *(S/N: 3214A00704: consecutive units!)
>
>? ?* Upon staring it, it stated "CALIBRATION FACTOR CHECKSUM ERROR. MOVE REAR
>? ? ?PANEL CAL SWITCH TO UNPROTECTED. POWER INSTRUMENT OFF AND THEN ON AGAIN.
>? ? ?RE-CAL INSTRUMENT."
>? ?* It also says "Trying to start realtime clock (09290)." Maybe that's an
>? ? ?error code?
>? ?* Upon switching the rear Cal switch to UNPROTECTED, it boots successfully,
>? ? ?goes to a default measurement screen, but gives me a warning "Failed
>? ? ?interpolar cal." The trace seems to jump around on Y a bit.
>? ?* Self Test passes all /but/ Timebase. It also displays the same error as
>? ? ?default screen ("Failed interpolar cal").
>? ?* 5V out at DC Cal is good.
>? ?* This one had the Cal switch in UNPROTECTED position, so maybe that's why
>? ? ?it booted successfully.
>? ?* I'm able to display the square wave test signal from the front panel,
>? ? ?though it seems to be offset vertically a bit.
>
> To me, this seems to tell me the battery holding the cal constants is done -
> going by what I know about my 54522A. It's also possible some Dallas RAMs are
> out of battery - though I don't know if this uses those for non-volatile
> memory. I have not yet opened the units, so I've no idea where the rails are,
> if any caps have leaked, etc. But maybe the information above gives some clues
> on what's going on, enough to start thinking on it. It also seems the issues
> are shared very similarly, so maybe that's making the repair more streamlined.
> Looking forward to your input.
> Thank you,
> Radu.
>
|
Peter - Yes, there are Keysight engineers who monitor the list and are very helpful, but my experience is that they are very rare. My particular question applied to a model of the FieldFox that is current production, and I received no help whatsoever (unfortunately).
?
Whit
--
Whitham D. Reeve
Anchorage, Alaska USA
---
|
Thanks everyone for your replies and suggestions. This is the kind of information I was hoping for.
?
Whit
--
Whitham D. Reeve
Anchorage, Alaska USA
---
|
Re: Thoughts on Hakko FR301
Hi,
?
I would not try to do this without the option to preheat the board to around 80C.
The problem is that it really hard to extract the 56pins in one go.
?
I my suggestion is to use ChipQuick on a preheated board to lower solder the melting
temperature to below 100C and use a heatgun to heat all 56pin in one go.
Lift the connector and clean with a cotton swab and more flux and a little heat.
?
To clean out the holes a compressed air gun might be of help while still heating.
?
ChipQuick and Chip Quik Flux are available at Mouser and other distributers.
there versions for lead and lead free soldering.
?
6 layerboards are really hard as its takes away a lot of heat and true holes
connecting multiple layer are easly damaged.
?
Good luck | Regard Rens
?
|
Re: HP 8660B/86602B developed output stability problem, getting-started suggestion(s) request
TinySA Ultra used to check outputs from the 11707A (except for the two 11661B-related outputs, as I forgot to enable the "Ultra" mode for coverage > 800 MHz.
The 500, 100, 20 and 350-450 MHz signals are stable and within spec except for the 350-450 MHz signal which is about 1 dB below minimum power spec.
The 20-30 MHz signal is unstable - while it has about -7 dBm output level (attached photo from the spectrum analyzer is down 10 dB as I have a 10 dB pad in the input path), the frequency is not stable, and the center frequency wanders (I'm not sure of the total extent of the frequency instability yet.) Spectrum analyzer display is attached.
The interesting thing at this point is that the spectrum display from the 20-30 MHz signal has the same deficiencies as the output from the generator itself. I do not know the expected frequency from the 20-30 MHz signal (the generator is in it's power-up frequency of 1.000 MHz), however, it is about 29.7 MHz, and measurements from the generator's output when I initially suspected a problem were routinely 250-300 kHz below the frequency entered on the keypad.
I've done no further testing (need get the TinySA Ultra into it's GHz-capable mode - this is no secret, just need find the appropriate instruction) so I can check the 2.75-4.05 GHz signals available on the 11707A.
Thanks again for the suggestions/help!
Dave
|
Re: Searching parts for HP 5370B
I can't help with the front panel frame, but I might be able to help with the filter.? I had to replace the one on my unit and ended up machining one out of 1/16" red acrylic and then using a vinyl stencil to pain on lettering.? I'll take pictures when I get home later and can share the fusion360 design files if you want
|
Re: HP Agilent 8753ES VNA repair [Help]
Matt,
What do you see if you display the A, B, and R with MEAS/INPUT_PORTS? ?? (I assume menus are similar the the 8753D)
On my 8753D, the R channel is at about 0dB displayed (with some ripple) and A is also about 0dB if the port is open.
--John Gord
?
|
Re: HP 8660B/86602B developed output stability problem, getting-started suggestion(s) request
Hi Ed, WB2UAQ ---
Thank you both for quick and helpful replies!
Ed - with your suggestion, I remembered that I do have a 11707A and it is now in the unit (I've never used it before as I've not had a 8660 failure, and I don't believe I've ever heard of a 11707A manual).
I also remembered that I have a 08660-90070 8660A/B/C service manual, which makes use of the 11707A test plug-in (an
online search for 11707A pointed me to that manual which makes use of it.)
Using the 08660-90070 manual, I am beginning tests:
The power supply voltage measurements on page first requiring those tests all show within spec.
The 350-450 MHz output is a couple of db below minimum spec (measured using 436A/8484A with 40 dB inline attenuator); all of the other RF level test points on the 11707A are above minimum spec.
I am now recharging TinySA Ultra (covers to 800 MHz) so I can look at the signal quality.
Thanks again, I'll update once I have any more specific results.
Dave
|
Re: HP Agilent 8753ES VNA repair [Help]
Hi, ? I did some tests on my working 8753ES. These results could be used for comparison. ? Yves
|
Re: 8596E Spectrum Analyzer Fault
Instead of START / STOP, try entering as CENTER and SPAN. ?Just to see if it freezes when it has enough info to start a sweep, or if it is related specifically to the sweep defined by entering the STOP frequency.
?
Does it sweep when first powered on, or after preset..?
?
Trying to get at whether this is a problem with the sweep synthesis set up, or something related to keypress handling...
|
Re: HP 54512B (pair) repair
Awesome, thank you, Peter.? I wonder if anyone has a fresh recollection of what battery or maybe battery-backed RAM would be suspect and possibly needed so I'd start working on an order to have the parts ready by the time I carve out some time to open these. From what I know about these generation scopes, replacing the battery is probably a good idea anyway. The cal constants seem to be gone, so nothing to lose there.? I wasn't able to find this information (particularly info on the battery) in the manuals, which I find odd.?
On Tue, Feb 25, 2025 at 5:26?AM Peter Gottlieb via <hpnpilot= [email protected]> wrote: Seems like you are on the right track.? Many HP scopes of that era lose their
minds if the memory battery goes dead.
Peter
On 2/24/2025 11:09 PM, Radu Bogdan Dicher via wrote:
> Hi all,
> Over the weekend I've got a couple of 54512Bs at my desk to seek to bring back
> to full functionality. My main scope is a 54522A, and I assume they have some
> commonalities, but I've yet to open mine (it came to me fully refurbished and
> never needed to open the case). I'm not very familiar with this other series,
> and hope on some good input and recommendations.
> The documentation is not as good as others I've seen from HP. Specifically for
> this unit (54512B), Keysight only seems to have a very skinny (by HP
> standards) Service Manual which can't honestly be called "module-level Service
> Manual," as it doesn't really into much detail on the different modules. Then
> there's a "Front Panel Reference," which is an odd other way of naming what I
> think is the Operating Manual. A couple other manuals have to do with
> programming. That's it.
> Sometimes in a series you have to look for the main unit, but in this case I'm
> not sure that's the 54501A, as the catalog spec sheet seems to suggest, or the
> 54505B, as per the SM. Maybe someone very familiar with the series would know.
> Artek doesn't have manuals for the 54512B at all, but they do for the 54501A,
> and if applicable, I'd get the series of six manuals they sell as a bundle. If
> no go, I'll be a bit in a bind with fixing this given what I have at hand. I
> am aware HP was not longer offering component SMs by this point, though I
> don't know for a fact on this specific series and scope (but I do regarding
> the better?/later? 54522A).
> Is this really capable of FFT to 500MHz, even if the scope is rated to 300MHz?
> I can't make sense of that.
> Now, on to the specific issues with the units.
> *Unit #1 *(S/N: 3214A00705)
>
>? ?* Upon starting it, it reports something like "TRYING TO START REALTIME
>? ? ?CLOCK," which is unsuccessful after a time countdown from I think 60:
>? ? ?"REALTIME CLOCK FAILED TO START - DISABLED."
>? ?* Once I get it to display the default screen and output a trace, it stated
>? ? ?"Default cal loaded. Re-cal instrument."
>? ?* Self Test passes all.
>? ?* I'm also seeing a solid and apparently accurate 5V from the DC Cal output
>? ? ?in the back. I haven't tried the AC Cal output.
>? ?* Note this one had the Cal switch in the back in the UNPROTECTED position
>? ? ?when I got it.
>? ?* I'm able to display the square wave test signal from the front panel.
>
> *Unit #2 *(S/N: 3214A00704: consecutive units!)
>
>? ?* Upon staring it, it stated "CALIBRATION FACTOR CHECKSUM ERROR. MOVE REAR
>? ? ?PANEL CAL SWITCH TO UNPROTECTED. POWER INSTRUMENT OFF AND THEN ON AGAIN.
>? ? ?RE-CAL INSTRUMENT."
>? ?* It also says "Trying to start realtime clock (09290)." Maybe that's an
>? ? ?error code?
>? ?* Upon switching the rear Cal switch to UNPROTECTED, it boots successfully,
>? ? ?goes to a default measurement screen, but gives me a warning "Failed
>? ? ?interpolar cal." The trace seems to jump around on Y a bit.
>? ?* Self Test passes all /but/ Timebase. It also displays the same error as
>? ? ?default screen ("Failed interpolar cal").
>? ?* 5V out at DC Cal is good.
>? ?* This one had the Cal switch in UNPROTECTED position, so maybe that's why
>? ? ?it booted successfully.
>? ?* I'm able to display the square wave test signal from the front panel,
>? ? ?though it seems to be offset vertically a bit.
>
> To me, this seems to tell me the battery holding the cal constants is done -
> going by what I know about my 54522A. It's also possible some Dallas RAMs are
> out of battery - though I don't know if this uses those for non-volatile
> memory. I have not yet opened the units, so I've no idea where the rails are,
> if any caps have leaked, etc. But maybe the information above gives some clues
> on what's going on, enough to start thinking on it. It also seems the issues
> are shared very similarly, so maybe that's making the repair more streamlined.
> Looking forward to your input.
> Thank you,
> Radu.
>
|
Re: HP 54512B (pair) repair
Seems like you are on the right track.? Many HP scopes of that era lose their minds if the memory battery goes dead.
Peter
toggle quoted message
Show quoted text
On 2/24/2025 11:09 PM, Radu Bogdan Dicher via groups.io wrote: Hi all,
Over the weekend I've got a couple of 54512Bs at my desk to seek to bring back to full functionality. My main scope is a 54522A, and I assume they have some commonalities, but I've yet to open mine (it came to me fully refurbished and never needed to open the case). I'm not very familiar with this other series, and hope on some good input and recommendations.
The documentation is not as good as others I've seen from HP. Specifically for this unit (54512B), Keysight only seems to have a very skinny (by HP standards) Service Manual which can't honestly be called "module-level Service Manual," as it doesn't really into much detail on the different modules. Then there's a "Front Panel Reference," which is an odd other way of naming what I think is the Operating Manual. A couple other manuals have to do with programming. That's it.
Sometimes in a series you have to look for the main unit, but in this case I'm not sure that's the 54501A, as the catalog spec sheet seems to suggest, or the 54505B, as per the SM. Maybe someone very familiar with the series would know. Artek doesn't have manuals for the 54512B at all, but they do for the 54501A, and if applicable, I'd get the series of six manuals they sell as a bundle. If no go, I'll be a bit in a bind with fixing this given what I have at hand. I am aware HP was not longer offering component SMs by this point, though I don't know for a fact on this specific series and scope (but I do regarding the better?/later? 54522A).
Is this really capable of FFT to 500MHz, even if the scope is rated to 300MHz? I can't make sense of that.
Now, on to the specific issues with the units.
*Unit #1 *(S/N: 3214A00705)
* Upon starting it, it reports something like "TRYING TO START REALTIME
CLOCK," which is unsuccessful after a time countdown from I think 60:
"REALTIME CLOCK FAILED TO START - DISABLED."
* Once I get it to display the default screen and output a trace, it stated
"Default cal loaded. Re-cal instrument."
* Self Test passes all.
* I'm also seeing a solid and apparently accurate 5V from the DC Cal output
in the back. I haven't tried the AC Cal output.
* Note this one had the Cal switch in the back in the UNPROTECTED position
when I got it.
* I'm able to display the square wave test signal from the front panel.
*Unit #2 *(S/N: 3214A00704: consecutive units!)
* Upon staring it, it stated "CALIBRATION FACTOR CHECKSUM ERROR. MOVE REAR
PANEL CAL SWITCH TO UNPROTECTED. POWER INSTRUMENT OFF AND THEN ON AGAIN.
RE-CAL INSTRUMENT."
* It also says "Trying to start realtime clock (09290)." Maybe that's an
error code?
* Upon switching the rear Cal switch to UNPROTECTED, it boots successfully,
goes to a default measurement screen, but gives me a warning "Failed
interpolar cal." The trace seems to jump around on Y a bit.
* Self Test passes all /but/ Timebase. It also displays the same error as
default screen ("Failed interpolar cal").
* 5V out at DC Cal is good.
* This one had the Cal switch in UNPROTECTED position, so maybe that's why
it booted successfully.
* I'm able to display the square wave test signal from the front panel,
though it seems to be offset vertically a bit.
To me, this seems to tell me the battery holding the cal constants is done - going by what I know about my 54522A. It's also possible some Dallas RAMs are out of battery - though I don't know if this uses those for non-volatile memory. I have not yet opened the units, so I've no idea where the rails are, if any caps have leaked, etc. But maybe the information above gives some clues on what's going on, enough to start thinking on it. It also seems the issues are shared very similarly, so maybe that's making the repair more streamlined.
Looking forward to your input.
Thank you,
Radu.
|
Re: Thoughts on Hakko FR301
And the likely price difference is worth paying in strides. I've said this before - in full agreement?with Dave McGuire - but there's no price that's too high to get good, well working tools. The?best tool for the job is the right decision 100% of the time.?
On Tue, Feb 25, 2025 at 5:20?AM Radu Bogdan Dicher via <vondicher= [email protected]> wrote: I think once one gets to use?both kinds of units - "pistol" type like the FR301, and "pen" type like an SX-80/90/100 by Pace, for instance - the advantages become very clear.? I've converted friends to the latter kind, but you really have to try both to see how much better the second type is. Once they tried it, they sold themselves,?and I didn't need to explain anything anymore.? Radu.?
Bought one a few years ago and wish I had bought it sooner.
?
It is really a fun tool to use, and having enough heat will not be a problem. I usually keep mine on the "2.5" setting or so, which offhand, I think is about half.
?
I've done boards with hundreds of pins and using this tool is pretty fun. There's a certain technique to learn to apply the right amount of pressure, for the right amount of time, to not inadvertently start lifting pads/start burning the board. One locked in, I can remove a 40-pin IC in a minute.
?
Like any tool, you've got to keep it clean, replace the filters, good videos on YT showing how. You'll lose suction otherwise.?
?
In my last session, I discovered how hot the cleaning pin gets that you ram down the barrel while the iron is hot so that no solder gets stuck. Don't touch it. :)
?
Love mine for general hobbyist use.?
Keith
|
Re: Thoughts on Hakko FR301
I think once one gets to use?both kinds of units - "pistol" type like the FR301, and "pen" type like an SX-80/90/100 by Pace, for instance - the advantages become very clear.? I've converted friends to the latter kind, but you really have to try both to see how much better the second type is. Once they tried it, they sold themselves,?and I didn't need to explain anything anymore.? Radu.?
Bought one a few years ago and wish I had bought it sooner.
?
It is really a fun tool to use, and having enough heat will not be a problem. I usually keep mine on the "2.5" setting or so, which offhand, I think is about half.
?
I've done boards with hundreds of pins and using this tool is pretty fun. There's a certain technique to learn to apply the right amount of pressure, for the right amount of time, to not inadvertently start lifting pads/start burning the board. One locked in, I can remove a 40-pin IC in a minute.
?
Like any tool, you've got to keep it clean, replace the filters, good videos on YT showing how. You'll lose suction otherwise.?
?
In my last session, I discovered how hot the cleaning pin gets that you ram down the barrel while the iron is hot so that no solder gets stuck. Don't touch it. :)
?
Love mine for general hobbyist use.?
Keith
|
Re: Thoughts on Hakko FR301
Bought one a few years ago and wish I had bought it sooner.
?
It is really a fun tool to use, and having enough heat will not be a problem. I usually keep mine on the "2.5" setting or so, which offhand, I think is about half.
?
I've done boards with hundreds of pins and using this tool is pretty fun. There's a certain technique to learn to apply the right amount of pressure, for the right amount of time, to not inadvertently start lifting pads/start burning the board. One locked in, I can remove a 40-pin IC in a minute.
?
Like any tool, you've got to keep it clean, replace the filters, good videos on YT showing how. You'll lose suction otherwise.?
?
In my last session, I discovered how hot the cleaning pin gets that you ram down the barrel while the iron is hot so that no solder gets stuck. Don't touch it. :)
?
Love mine for general hobbyist use.?
Keith
|
Re: HP 8660B/86602B developed output stability problem, getting-started suggestion(s) request
If you can locate an HP 11707A test plug in, it can be a bog help. It brings many of the signals out to the front of the unit for easy access.
Unfortunately I do not see any on EBAY...
|
Re: Thoughts on Hakko FR301
The Hakko FR301 is the only desoldering gun I have direct experience with.? I bought one after years of just using wick, iron, and heat gun or all 3.? I was thoroughly impressed with how well it worked.? I have heard anecdotely that earlier versions of this gun did have heating element issues, but that they were resolved in the newest revision.? I also like how easy it is to clean and service.? It also heats up very quickly.??
|
Re: Thoughts on Hakko FR301
Sergey,
I appreciate your input.
Yes there is a trailing power cord but in comparison to some other desoldering handpieces that have both a power cord and a vacuum line having only one item helps make the unit more maneuverable.
You obviously do not have a good impression of the FR301. I do. And I appreciate your impressions of it and possibly you have had a bad experience with one in the past. I have had excellent good success using it over the years. I favor it over all of the Metcal, Kurtz Ersa and Weller units in the lab for desoldering when a quick part removal is needed. It is also nice in the field since you don’t have a lot of extra hardware trailing behind you.
As for removal of certain items of which you indicated that you choose various other approaches and accessories to use, we choose various other methods outside of simple heated desoldering equipment. One such approach is use of non-contact variable focus IR desoldering units with pinpoint accuracy so as not to mechanically disturb the joints except for drawing the solder away from the target area. This eliminates having to “scrub” a tip over the PWB pad area thereby minimizing any damage that could occur. You would probably find a custom machine of this type to be excessively expensive to obtain (~>$2000 - $2500). These are very esoteric machines and are not for a hobbyist.
As for the “sledgeghammer” and “abomination” opinions I am sorry that you find the FR301 to not meet your needs. We are not all alike and such opinions are purely the impression of the particular user. I do not consider the FR301 to be of that ilk. My arms have never complained and there has never been any damage to the boards and other circuitry that we work on even when having to comply with commercial, aerospace and military soldering standards required by some of our clients.
Greg
|
Hi all,
Over the weekend I've got a couple of 54512Bs at my desk to seek to bring back to full functionality. My main scope is a 54522A, and I assume they have some commonalities, but I've yet to open mine (it came to me fully refurbished and never needed to open the case). I'm not very familiar with this other series, and hope on some good input and recommendations.
?
The documentation is not as good as others I've seen from HP. Specifically for this unit (54512B), Keysight only seems to have a very skinny (by HP standards) Service Manual which can't honestly be called "module-level Service Manual," as it doesn't really into much detail on the different modules. Then there's a "Front Panel Reference," which is an odd other way of naming what I think is the Operating Manual. A couple other manuals have to do with programming. That's it.?
?
Sometimes in a series you have to look for the main unit, but in this case I'm not sure that's the 54501A, as the catalog spec sheet seems to suggest, or the 54505B, as per the SM. Maybe someone very familiar with the series would know. Artek doesn't have manuals for the 54512B at all, but they do for the 54501A, and if applicable, I'd get the series of six manuals they sell as a bundle. If no go, I'll be a bit in a bind with fixing this given what I have at hand. I am aware HP was not longer offering component SMs by this point, though I don't know for a fact on this specific series and scope (but I do regarding the better?/later? 54522A).?
?
Is this really capable of FFT to 500MHz, even if the scope is rated to 300MHz? I can't make sense of that.?
?
Now, on to the specific issues with the units.?
?
Unit #1 (S/N: 3214A00705)
- Upon starting it, it reports something like "TRYING TO START REALTIME CLOCK," which is unsuccessful after a time countdown from I think 60: "REALTIME CLOCK FAILED TO START - DISABLED."
- Once I get it to display the default screen and output a trace, it stated "Default cal loaded. Re-cal instrument."
- Self Test passes all.?
- I'm also seeing a solid and apparently accurate 5V from the DC Cal output in the back. I haven't tried the AC Cal output.?
- Note this one had the Cal switch in the back in the UNPROTECTED position when I got it.?
- I'm able to display the square wave test signal from the front panel.?
?
Unit #2 (S/N: 3214A00704: consecutive units!)
- Upon staring it, it stated "CALIBRATION FACTOR CHECKSUM ERROR. MOVE REAR PANEL CAL SWITCH TO UNPROTECTED. POWER INSTRUMENT OFF AND THEN ON AGAIN. RE-CAL INSTRUMENT."?
- It also says "Trying to start realtime clock (09290)." Maybe that's an error code???
- Upon switching the rear Cal switch to UNPROTECTED, it boots successfully, goes to a default measurement screen, but gives me a warning "Failed interpolar cal." The trace seems to jump around on Y a bit.?
- Self Test passes all but Timebase. It also displays the same error as default screen ("Failed interpolar cal").?
- 5V out at DC Cal is good.?
- This one had the Cal switch in UNPROTECTED position, so maybe that's why it booted successfully.?
- I'm able to display the square wave test signal from the front panel, though it seems to be offset vertically a bit.?
?
To me, this seems to tell me the battery holding the cal constants is done - going by what I know about my 54522A. It's also possible some Dallas RAMs are out of battery - though I don't know if this uses those for non-volatile memory. I have not yet opened the units, so I've no idea where the rails are, if any caps have leaked, etc. But maybe the information above gives some clues on what's going on, enough to start thinking on it. It also seems the issues are shared very similarly, so maybe that's making the repair more streamlined.?
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Looking forward to your input.?
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Thank you,
Radu.?
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Re: Thoughts on Hakko FR301
On 2/24/25 22:29, Sergey Kubushyn wrote: You don't have a vacuum hose to a soldering station but you have a hammer
(motor/turnine) in your very hand that is supposed to do a precise delicate
job of proper positioning, than activating and deactivating vacuum. Then,
you have to struggle with a jump caused by motor rotor inertia when it
starts. Mine doesn't jump at all when triggered. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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WReeve
Keith Monahan
Frank Mashockie
Dave McGuire