EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: JonH88 on February 13, 2022, 10:21:09 am
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Repair Log:
I was given a Bruel & Kjaer 2144 Dual Channel Real Time Frequency Analyzer to repair. The unit would not power up and I could not find any schematics. I checked the removeable mains to 12V power module and this was OK I then started to look at the dc-dc converter board. I could not find any immediate component fault so I looked at how the dc-dc converter was actually triggered 'on'. I found that the trigger voltage was derived from the CPU memory backup battery which, as the unit had been in storage for a while, was flat. The power-on trigger operates through an opto coupler on the dc-dc converter board. You can access the positive terminal at the top of the 3.6v battery (see photo) so the unit was 'jump started' by injecting a small current (c.30mA) onto this terminal until the battery had sufficient charge to operate the power-on opto. The unit powered up but because the CPU memory battery was flat, the program software was lost and as I don't have any software the unit can't be used at present. I later replaced the CPU memory battery as it would not hold charge.
Software:
I contacted B&K in UK about obtaining software and whilst they were helpful, they could not find any software for this model in their archives. I followed up on B&K's response to ask whether it was acceptable to obtain a copy of the software from another user (i.e. no copyright / IPR issues). B&K checked and confirmed that this would be OK. I don't know the details of the software that is available for this unit. I would like to restore its functions as a basic low frequency analyser. Perhaps the blog contributors can help me find some software to make this unit operate.
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I can't help you with software but wanted to say 'good troubleshooting'. Hope you get it going.
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If it's the software described in the attached PDF then it's not very exciting, MSDOS & LPT ports, yuk.
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If it's the software described in the attached PDF then it's not very exciting, MSDOS & LPT ports, yuk.
There seem to be several options available, including bootstrapping the device from the IEC port, but the one you mention is not the bootdisk for the standalone analyzer.
I believe something like the one below is the one being referenced. This is from an eBay listing for a whole package with a quite stiff price, of the version of the 2144 with the "Type 7651" FFT software-key installed. There's a similar "Real-Time Analyzer Software" for the base 2144 without the extra key, and a similar pair of software disks for the single-channel 2143 (this last one is on Archive.org, not sure if it can be loaded on the 2144).
But me too will probably soon join the group of people who need a boot disk for the 2144. Lets see when the box arrives.
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Don't know if this is any help for you, but I have a (spare) 2133 including original software disks.
The spare 2133 is not booting due to a malfunction psu. The other one starts up
If you need more info send me a pm.
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Ok, my unit arrived. I had my hopes up since there was a floppy-disk in the drive, but after archiving it I see that it only contains two deleted measurement logs. So, no firmware-disk here either.
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A small update, I helped RAPo with archiving the software for this 2133 (laboratory "non-portable" benchtop audio analyzer) and put a copy on the Internet Archive too, and while this is a different format than the software for the 2143/2144, I think it may be of help to at least someone out there.
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Excellent service from Frodo!!.
A small update, I helped RAPo with archiving the software for this 2133 (laboratory "non-portable" benchtop audio analyzer) and put a copy on the Internet Archive too, and while this is a different format than the software for the 2143/2144, I think it may be of help to at least someone out there.
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Good news, I was able to source the firmware of Type 7667, which is the filter program firmware for the 2148. Turns out it works with the standard 2144 as well! Very many thanks to the seller on Ebay who had a copy he was able to read out. I was buying something else Brüel & Kjær related from him when he mentioned someone had donated a whole audio-lab to his warehouse, and that led me to asking.
One note, my unit has license keys VP5267 and VP5278 installed. Of these, VP5267 is required to run this software. I do not know what VP5278 is for, but what I can say is that it is at least not for this nor for the Zwicker Loudness application (which the guy also sent me a copy of the firmware for).
I will eventually upload it to the Internet Archive when they get their stuff patched up and working again.
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After some investigation, I am pretty sure the other key is for the FFT Analyzer program. In other words:
- VP5267 key: Dual ch. Digital Filter program (Type 7667)
- VP???? key: Single ch. Digital Filter program (Type 7666)
- VP5278 key: Dual ch. FFT Analysis program (Type 7651)
- VP???? key: Single ch. FFT Analysis program (Type 7669)
- VP???? key: Zwicker Loudness program (Type 7638)
- VP???? key: Vehicle Signal Analysis program (Type 7668)
I cannot seem to find any other software that was made to run directly on the 2143/2144, but there are a few other programs that seem to be designed to run on a PC with an analyzer connected. These analyzers are also able to boot code via GPIB, so I may guess certain of those PC-programs will take use of that feature.
Besides this, from reading some of the manuals, it seems like the 2144 came default with the key for Type 7667, while the 2148 came default with the key for Type 7651. Otherwise these two models should be identical. 2145 and 2146 seems to be more specialized, being a "Vehicle Signal Analyzer" and "Sound Level Analyzer" respectively. I guess these follow the same pattern, coming bundled with Type 7668/7638 keys by default, but these may have other differences in hardware in addition to just license-keys. From a parted-out unit on Ebay, for instance, I see that the 2145 has an additional third DSP card whereas the 2144/2148 only have two.
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Good news indeed! :--