Re: [time-nuts] Looking for a low power very low noise DC/DC converter (100 - 200 ma 10VDC or 15VDC)

2016-10-31 Thread Bob Camp
Hi …. or you could do a milled box inside a milled box inside a milled box. Isolate each one from the others. Filter all leads at each “goes in” and each “goes out”. Put the input side in it’s own cavity in each box. Put the output side in it’s own cavity. Put the control signals in their own s

Re: [time-nuts] Looking for a low power very low noise DC/DC converter (100 - 200 ma 10VDC or 15VDC)

2016-10-31 Thread ed breya
I should mention that the input supply filtering to the DC-DC converter should have good attenuation at the switching frequency, but not at low frequencies, so there's no need to get carried away with the size of the filtering at the converter input. Too much filtering, especially inductance, c

Re: [time-nuts] Looking for a low power very low noise DC/DC converter (100 - 200 ma 10VDC or 15VDC)

2016-10-31 Thread ed breya
Yes, for best quietness, you definitely should "can it up" in a metal box, and use feed-through caps for all the I/O, including the commons or grounds. You have to figure out also where all the currents flow, and contain the loops. With sufficient L-C filtering on the input and output (all insi

Re: [time-nuts] Looking for a low power very low noise DC/DC converter (100 - 200 ma 10VDC or 15VDC)

2016-10-31 Thread Christopher Brown
On 10/30/16 22:17, Poul-Henning Kamp wrote: > > In message , Christopher > Brown writes: > >> Could not find anything with really good specs so am currently thinking >> something like a Traco TDN 3-1213WI (200ma 15V) feeding a filter into a >> low noise linear reg to -10VDC followed by

Re: [time-nuts] Looking for a low power very low noise DC/DC converter (100 - 200 ma 10VDC or 15VDC)

2016-10-30 Thread Poul-Henning Kamp
In message , Christopher Brown writes: >Could not find anything with really good specs so am currently thinking >something like a Traco TDN 3-1213WI (200ma 15V) feeding a filter into a >low noise linear reg to -10VDC followed by another filter. Look at their TVN 5WI instead ? If you wa

[time-nuts] Looking for a low power very low noise DC/DC converter (100 - 200 ma 10VDC or 15VDC)

2016-10-30 Thread Christopher Brown
Not entirely on subject since this is for a transceiver, but figured this would be the group most likely to generate a useful answer. I happen to like the older Icom IC-271H and 471H, I have a pair of each where one is currently the control and one is the in-progress unit. All the normal stuff