[time-nuts] SMD TADD-1 distribution amplifier - seeking comments and suggestions?

Anders Wallin anders.e.e.wallin at gmail.com
Mon Nov 30 20:02:28 UTC 2015


HI all,
I need to build a few distribution amplifiers (>90% for 10MHz, sometimes
maybe 5MHz) and instead of reinventing the wheel I decided to try to
modernize the TADD-1 into an all (almost) SMD design. Here are some draft
sketches:
http://www.anderswallin.net/2015/11/frequency-distribution-amplifier-plans-a-k-a-smd-tadd-1/

Does this sound/look reasonable or crazy?
Any suggestions for op-amps to try and/or compare to the AD8055?
What causes the extra phase-noise below 1 Hz offset in John A's result:
https://www.febo.com/pages/amplifier_phase_noise/amplifier_phase_noise.png

Suggestions for a low noise DC-regulator circuit? The 12-24VDC supplied to
this board will most likely come from a switched-mode PSU, so filtering of
common-mode noise is mandatory.
I found the TI LP38798 shown in the schematic by googling - if someone has
a proven a measured design that would be a safer choice. In any case more
filtering (e.g. ferriites) is probably a good idea.

This design will be available on my blog or on github when it is done - if
anyone is interested.

Thanks,
Anders



More information about the Time-nuts_lists.febo.com mailing list