Digital interface components

Projects Reference Development Kit
1

Hi,
I realized the pcb of the digital interface board (V1.0) and I am trying to solder the components .
Should I welded components rated NF ?

2

Hi,

NF stands for - No Fit. Do not solder components marked as NF unless you are looking for some specific board configuration.

3

Hi Ricardas,
Thank for the information.

4

Hi,
I can’t find the oscillator (Rakon E5280LF) with my suppliers. Have you the datasheet of this component ?
You know an equivalent ?

Cheers

5

Hi ritchy,

To get Rakon oscillator parts you need to contact Rakon [link].

6

Dear LimeSDR community and @Zack,

I would like to use the current 30.72 MHz oscillator mentioned above (XO2, Rakon E5280LF, LimeSDR-USB 1v4). However, I assume both Oscillators (XO1 and XO2) are mixed up in the schematic (see question at the end).

I contacted Rakon and they send me the official datasheet for the E5280LF 30.720 MHz TCVCXO. If you look at the datasheet (page3) it shows the following outline:

But on the board the oscillator looks different:

I assume a mistake in the schematic. It shows two oscillators: The XO2 and the XO1 (marked as NF):

image.png449×538 9.42 KB

The XO1 (E6245LF, RAKON_RPT7050A) might be the right one, as it looks exactly as on the board:

1. Question: Could it be that the two components have been mixed up and the XO2 should be NF?
2. Question: If not, what is the reason for chose the XO2 vs. XO1?

Sorry for re-activating the thread and thank you!
Sombrero

7

FWIW, I checked my v1.4 board and I have RPT7050A (part marked as E6245-PY). Which schematic are you looking at?

Datasheet pdf:
http://www.rakon.com/products/families/download/file?fid=39.225

http://www.rakon.com/products/families/tcxo

This part is spec’d in the BOM:

https://github.com/myriadrf/LimeSDR-USB/blob/master/hardware/socket/1v4/Project%20Outputs%20for%20LimeSDR-USB_1v4s_LMS031pad/BOM/LimeSDR-USB_1v4s_BOMr7.xls

8

That is exactly the reason why I wrote the last post. It looks like the XO1 is the part which was used. But it is marked as NF in the clocks schematic of the v.1.4 board (USB, plug).

After analyzing this with Rakon I can verify that the XO1 is the correct oscillator. Partname: RPT7050P (E6245LF/512251). The XO2 should be marked as NF, they are mixed up in the clocks-schematic.

Would be happy to get a short verification from Lime. (@Zack, @andrewback)

Thank you.
Best regards
Sombrero

9

Hi @Sombrero,

It is E6245LF on 1v4 boards. And you are correct, XO1 is correct oscillator. Thank you for spotting this!