Hi Adri,
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Yes, I am curious, you can send me a video on the intermittent noise problem, by going through OneDrive for example, or Dropbox.
It could be that one of the PLLs is the cause.
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For the 8595E on which I was trying to repair, the problem was not on the 130 option as the error message seemed to indicate, but rather an incorrect alignment on the basic filters.
The AMP CAL stopped because it was unable to find the two -3dB points of a filter.
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Yes, I realigned all the filters following the procedure in the service manual.
There are 4 crystal filter sections and 4 LC filters.
Simple procedure but a bit long, and you must not make any mistakes, otherwise you have to start from the beginning.
I did the job slowly; everything went well and the original problem was solved.
I recalibrated the instrument and took the opportunity to improve my software for flatness alignment, now after the test, all data is entered automatically...which speeds up the work.
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In my opinion, someone opened this 8595E to try to make a repair, the second converter had been opened, 2 screws were missing and 2 others were reset to 50%.
I had to realign the second converter after closing it correctly.
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For the filter section, it is clear that one touched the adjustments, because half were well aligned, and for the others, the adjustments were very far from the optimal value.
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In total, 8 screws were missing on this instrument.
Probably an interrupted repair¡
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Yves
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hello Yves, great repair that of the opt 130
In my case the opt 130 has always worked well and I have never needed to study it in detail
Did you do the realignment by adjusting the trimmers on the board itself?
The adventure with my 8595E continues
To sum up, after my last email I focused on a more accurate and uniform alignment of the SYTF. With the help of the microscope, a strong light source, a precision power supply and a fairly reliable frequency source I obtained an insertion loss as per the attached excel file
After reassembling the RF front-end everything worked fine again, including the MXR CAL routine that?used to?give the?error? "insufficient harmonics"
When I moved from the "messy" version (pic)? reinserting everything into its space (which is very crowded, also due to the existence, in my case, of the tracking gen)?and connected?the SA input to CAL OUT I observed a type of intermittent noise, in the form of spikes of intensity about -60dBm that appear and disappear in the area of ??the highest harmonics (I already checked the?CAL OUT signal; it?is clean and fine)
Now I think I will have to re-disassemble the front-end (ouch) and try to understand from where does this noise originate :-(?
If you are interested I?can send you a short video of the problem (don't think I?can post videos here)
Thanks for asking, Yves
Adri
