Afaik yes. Least I have adjusted it changing value: cali_freq_dac
This file include 6 bytes as: 0xdddd (dddd is for dac, originally in my individual unit dddd was ad2f and now it is aca8)
It can find in firmdata0/calib directory (and this directory have lot of cal data. Do not corrupt this directory. It is best that before any touching inside it using telnet and example PuTTY, first make back up copy from whole calib directory to USB and keep it save. If this data is corrupted, loosed, only factory can reproduce factory calibration data - without full cal data, it is like electronic recycle material).
This is fine adjust so do not change if you really are not sure you have enough good reference for check it.
Without enough good freq counter it can do also using example good accurate checked 10MHz Rb or good well set GPS DO using scope and clock for compare freqs and calculate difference. (I use HP 53131A with known good ref and 5s gate time)
In my SSA setting resolution is around 2.5mHz @ 10MHz Change value down and reference clock freq drops.
Note, all time you change value then need reboot. So best method is first measure exactly your ref error.
First measure exactly your reference freg after SSA is warmed 1 - 2 hour for perfect temperature equilibrium.
Then do enough big adjust, example + or minus 3E8 (very roughly perhaps 2.5 Hz @10MHz depending your individual SSA) and then you know how much it change freq. After then calculate how much you need adjust for null your freq error.
Good rule: Do not repair if not failed, do not adjust if there is not sure known real reason for need of adjustment and knowledge what exatly adjust and what all side effects or cross effect interactions it may do.
Disclaimer: I do not know what all kind of interactions it may have in system. I have no any idea how it works and how it affect and how it also may produce some bad effect, hidden or visible. So if some follow this, he is fully and alone responsible himself what ever happend.
Home
Help
Search
Login
Register
