Hi all, Based on the response to my distribution amplifier prototype&measurements I ran a few SPICE simulations with the old AD8055 design and an improved design.
The changes are: - better op-amp - improved DC-bias "T" circuit - lower resistance values (esp. gain-setting resistors) results & discussion in my blog: http://www.anderswallin.net/2015/12/frequency-distribution-amplifier-v2-simulations/ The simulations would indicate a 12 to 13 dB improvement in noise floor is possible. I could not find a good ADA4899-1 spice model. One has realistic AC gain response but unrealistic 1/f noise. The other model I found has a realistic 1/f noise but infinite AC gain bandwidth :( again suggestions are welcome, I'll probably order boards and parts for the next prototype in a few days. I will look at Bruce's suggestion for the BNX002 (SMD equivalent available?) on the powersupply. There is already a common-mode choke (TDK ZJYS) and an NFE61P before the regulator, as well as ferrites before the bypass-caps and vcc-pin of each output amplifier. thanks! Anders _______________________________________________ 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.