When buying test equipment, it is wise to stick to well known makes, because when there’s plenty around there is usually plenty information about how to keep them running.
Less well known makes suffer from lack of technical/repair information and lack of availability of spares. Even worse is units with parts missing, because you might not know bits are missing until later, you may not know what they are and lastly not know part numbers or even what they look like.
So…..
I recently bought the Rohde & Schwarz FSIQ26 ( bits missing ) analyser that had been on Ebay for quite a while. It was on 24hr delivery, so I checked tracking info, yes it had arrived at the local depot and was due for delivery the next day, so I waited in all day but nothing arrived. I waited in the next day and nothing arrived. I waited in the next day, still nothing arrived. I contacted the seller on the monday, she said she would contact the courier and get back to me. I also emailed the courier, their reply was basically “very sorry, tough, don’t contact us again, go thro the seller”. After 2 weeks nothing had been heard and the seller had refunded my payment, so in a last ditch attempt I wrote to the local shipping depot and the world wide operation’s director asking them to try and find it AND enclosing photos of what it looked like. A couple of days later I got a phone call saying the shipping label had come off but they identified it by my pictures. So after a 24hr delivery that stretched out to 3 weeks it finally arrived.
There was some service info available, the FSE manual which the FSIQ appears to be derived from, but there were several differences that lead to later confusion.
When it arrived I started by looking it over, checking for missing bits and loose wires. At first glance there was a gap where the attenuator should be, but I knew that from the auction pics, and there were a couple of R & S attenuators on Ebay so hopefully that shouldn’t be a problem. The vector analysis board was missing but that seemed to be all.
However there were 7 off RG316 cables cut thro, the floppy and attenuator ribbon cables had been cut in several places and a couple more power lines chopped. Also the rigid cable to the front panel input had been ripped out. Strange. The chassis rails and middle case support on the RHS were also missing.
Initial power up revealed a noisy hard drive so I shut down and backed this up. A bit of research suggests that if you try and back up using a windows machine, it will overwrite parts of the drive, however there is a Linux HD backup program called DDrescue which is supposed to be very good and does a byte for byte copy. As I had several to do, I put together a Linux machine, using an old Athlon 64X2 PC and loaded Linux Mint 18. This loaded very quickly, about 10mins in total.
I then tried to install DDrescue, but not being experienced in Linux systems, I couldn’t get this to install, however I came across a GUI version that installed perfectly and was very easy to drive. I backed up the HD onto a 4 G CF card and fitted it into a cheap and cheerful CF to IDE adaptor. Insulated off the metalwork and held in place with hot glue, this worked absolutely fine, and the FSIQ booted up.
It stopped at “enabling resources”, after some investigation, the problem was tied down to one of the Transputer cards, so I pulled the faulty one off the video card and it ran up to the analyser screen.
I repaired/replaced all the cut RF cables and it worked, a bit noisy but success !. I replaced the temporary input cable with a semi-rigid and noise level went way down.
Hang on its supposed to be 26GHz but input to the RF converter is SMA which is only good for about 18GHz and there is an unused MW converter module with an unconnected SMK socket in the vicinity ?. The FSE manual had no information about this, it only covered the 3.5GHz model, but a very helpful person at R & S ( thanks Stephanie ) passed on information about what should be there. It appears that as well as cutting all the cables, pulling out the 2 chassis rails and removing the input attenuator, someone has removed the diplexer that splits the input signal and routes up to 7GHz to the first converter and higher frequencies to the MW converter. A YIG filter and 1dB attenuator were also missing.
A search for case bits was unsuccessful, so I made a couple of chassis rails. I might be able to make a case for it, but trying to bend large sheets of aluminium without a proper shear and folder is a pain. All the R & S attenuators on fleabay are too low in frequency; I am currently using a couple of 10dB attenuators plugged into the front, and am looking at decoding the switching signals to drive an HP attenuator. I haven’t seen a diplexer or YIG filter yet.
Close but no cigar ?. It falls short of being the full 26 GHz and “only” does up to 7GHz, however that is still pretty useful ( above a Rigol ! ) and above my other kit. Its a pretty impressive machine and has lots of functions and facilities. The UI will take a bit of getting used to but all the professional stuff has a learning curve to get the most out of it.
I am curious as to why any sane person would rip a working analyser like this to bits and cut all the cables. Its as if they didn’t want it to work again ?.
Curious, another of life’s mysteries.
Ken
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