> Has anybody tried to replace these > fans with a > more modern type (12/24 volt). I'm sure the designers were being very > proper, but I cannot believe that a counter should require such a large > volume of air moving through it ? > I have an EIP 545 Counter and > an HP 5335A > which both have Papst fans and are very noisy > Any ideas on this. > Roy
The 5370 counters are unusually power-hungry, at about 160 watts for my 5370B. The airflow through the instrument is where the noise is coming from, not so much the fan itself (try powering the fan up outside the counter, holding it in your hand, and it'll be much quieter). Can't speak for EIP but I don't think it's a good idea to alter the factory airflow specs on HP gear, in most cases. >Now I'm wondering which software I could use to grab data from it to the PC >and then to analyze the buffers to see the stability of my rubidium >source synchronised with the 1pps coming from the GPS. I'm not sure it's possible to make continuous stability measurements (Allan deviation, etc.) directly with a 5370 since they don't support running/overlapped measurements between readings. If you can work with a 1-pps output and can provide a divider for your reference, it can be done with a picket-fence technique (e.g. http://horology.jpl.nasa.gov/papers/picket_uffc.pdf ) which I haven't tried yet. If anyone thinks it might be worthwhile, I could throw together a GPIB app to implement Greenhall's paper for the 5370B with a Prologix or NI board... but my guess is that most people have been using other gear for that sort of thing. -- john, KE5FX _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.