Chris, while there MAY be exceptions my rule of thumb is that none of the devices that I have seen until today was unhappy at a +7 dBm reference level. My own distibution amp runs at +13 dBm (quite handy to drive a level 13 mixer directly from a well isolated source) and I drive all my devices with that which include
HP3330 HP3325 HP5370 HP5342 HP5359 HP8660 SR-620 DS-345 UA6200A Wavetek 278 Racal-Dana 1996 Anritsu MS2601B without experiencing any problems. Don't look at the problem with the eyes of a ham: Unlike in most ham rf circuits a lot of these devices need to make a square shaped signal from the sine input and are happy if you support them with a not too small level. That is my experience but please don't take it as an invitation to test if EVERY device may be fed with 13 dBm without destruction. A look to the specs is never wrong. 73s de Ulrich, DF6JB P.S. Even if you consider that the reference input may have a 0805 50 Ohms chip resistor for termination its destruction level will be well above +20 dBm. > -----Ursprungliche Nachricht----- > Von: [email protected] > [mailto:[email protected]] Im Auftrag von Christopher Brown > Gesendet: Samstag, 31. Marz 2012 10:12 > An: Discussion of precise time and frequency measurement > Betreff: [time-nuts] External 10Mhz referance levels > > > > > So, going through a surplus HP 5087A. All torn down, cleaned > and back together. 10Mhz input amp and 10 output amps. > Manual talks about setting for 3V rms into 50ohms, all 10 > amps appear clean and a little extra time with a spec an > gives -55db at 30mhz and < -65 or better for the rest. > Dropping to 1V RMS and tweaking the balance pot gives -55 to > -60 at 20 and 30, rest in the noise. > > All seems good, but what should I be feeding my gear. All of > the manuals are pretty sparse on details, mentioning minimum > for a few, but no target or max. > > > Will be feeding > > 3596C > 5335A > 5370B > 8657B > 8395/E6380A > > to start. > > Maybe I am missing it, but the only mention of level I have > seen so far is > -10dbm. The suggested 3v rms in the 5087 > manual seems a bit high. > > Comments, suggestions, guidance? > > > BTW: Name is Chris, HAM since teens, playing with anything > technical for longer than I can remember, packet data > networking guy for last 18 years by day. Getting around to > putting together a decent workbench opposite the HAM station. > Never could stand owning/operating things I could not > properly service, fixing the issue but first I need to figure > out all the gear (and in some cases fix the gear that will be > fixing the other gear.). > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
