Re: [time-nuts] The difficulty of low noise measurements

2020-01-12 Thread Magnus Danielson
Hi, On 2020-01-12 17:08, Poul-Henning Kamp wrote: > > In message <95f82880-6cec-1885-c59e-046ab7a79...@rubidium.se>, Magnus > Danielson writes: > I have a ham friend that is fairly well into batteries as he needs to for his telecom installations. >>> LVDC people are much better

Re: [time-nuts] The difficulty of low noise measurements

2020-01-12 Thread Poul-Henning Kamp
In message <95f82880-6cec-1885-c59e-046ab7a79...@rubidium.se>, Magnus Danielson writes: >>> I have a ham friend that is fairly well into batteries as he needs to >>> for his telecom installations. >> LVDC people are much better at this than UPS people, the latter often >> think that batt

Re: [time-nuts] The difficulty of low noise measurements

2020-01-12 Thread Magnus Danielson
Hi, On 2020-01-11 21:53, Poul-Henning Kamp wrote: > > In message <643136da-9599-18ca-be85-ffa62ab04...@rubidium.se>, Magnus > Danielson writes: > >>> I have on my ever-growing TODO list to test if serial-BLE adapters >>> are any good. Has anybody tried that yet ? >> My recommendation is

Re: [time-nuts] The difficulty of low noise measurements

2020-01-12 Thread Didier Juges
Keep in mind that BLE and "classic" Bluetooth are completely different animals. There is no "serial emulation" with BLE. If you want to use Bluetooth modules to isolate serial traffic, I recommend the JDY-30/31 modules. They are a much improved (and cheaper) version of the HC-05 that you can get a

Re: [time-nuts] The difficulty of low noise measurements

2020-01-11 Thread Poul-Henning Kamp
In message <643136da-9599-18ca-be85-ffa62ab04...@rubidium.se>, Magnus Danielson writes: >> I have on my ever-growing TODO list to test if serial-BLE adapters >> are any good. Has anybody tried that yet ? >My recommendation is to build on the ESP32, then you can get serial port >to WiFi

Re: [time-nuts] The difficulty of low noise measurements

2020-01-11 Thread Poul-Henning Kamp
In message <454f3441-6479-cc54-7c1c-55f61b5fa...@earthlink.net>, jimlux writes: >That is an interesting idea. I wonder if you could make a short distance >fiber connection by just having your notional 10MHz source directly >drive the diode, with maybe a series resistor (so you don't nee

Re: [time-nuts] The difficulty of low noise measurements

2020-01-11 Thread Magnus Danielson
Hi, On 2020-01-11 18:57, Poul-Henning Kamp wrote: > At that level of the dungeon, you have a choice. > > You can either bolt *everything*, including the chair you sit on > and the pencil you write with, together with copperstraps to get a > common potential. Mesh Bonding Network [1] > > Or you can

Re: [time-nuts] The difficulty of low noise measurements

2020-01-11 Thread jimlux
On 1/11/20 9:57 AM, Poul-Henning Kamp wrote: At that level of the dungeon, you have a choice. You can either bolt *everything*, including the chair you sit on and the pencil you write with, together with copperstraps to get a common potential. Or you can arrange *all* your cables and other meta

Re: [time-nuts] The difficulty of low noise measurements

2020-01-11 Thread Poul-Henning Kamp
At that level of the dungeon, you have a choice. You can either bolt *everything*, including the chair you sit on and the pencil you write with, together with copperstraps to get a common potential. Or you can arrange *all* your cables and other metalic connections (cabinets touching because the

[time-nuts] The difficulty of low noise measurements

2020-01-11 Thread Magnus Danielson
Fellow time-nuts, As I now have a hydrogen maser sitting here, it triggers me to measure things. Essentially I try to measure the stability of the maser, and well, that will be very hard since one need very quiet reference sources to do that, but that then triggers the question of how quiet are my