Which must I follow more closely?
There are differences in small passive components between the downloaded SCHEMATIC, the MAKE documentation and the BOARD file components. I noticed this in particular with the CAPS in the PLL section:
SCHEMATIC:
C51 0.1uF
C63 1.0pF
BOARD (from partslist):
C51 1.0uF 1206
C63 1.0pF 0603
PLL MAKE DOCU: (all linked to 1.0uF 1206)
C51 1.0uF 0603
C63 1.0uF 0603
SCH and BRD and MAKE differences
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Please be positive and constructive with your questions and comments.
- none_such
- Posts: 76
- Joined: Mon Jun 12, 2006 1:16 pm
typo and where to find answers
There is a mistake in the typing on the PLL MAKE page. You should read a "," instead of a "-" between the C50 and C53 because values C50, C51, C52 and C53 are already defined on the VCO MAKE page and are in agreement with the WB schematics.
For the C63 value the specs for the SXA-389 say it should be 0.5 pF (+/- .25 pF) with an 18 or 15 nH inductor (and don't place C62) However, our WB schematics call for 1.0pF which sounds about right considering we are using a 22 nH inductor. High gain amplifiers have gates that are worked really hard to mimic a perfect switch and need to be tweeked for optimum efficiency so it doesn't really matter what we use in our WB since we are moving the frequency all over the place (that is the reason for the two VCO's)
R24 looks as if it is a compromise between using a 1.2 nH inductor and allowing RF thur.
Cheers
For the C63 value the specs for the SXA-389 say it should be 0.5 pF (+/- .25 pF) with an 18 or 15 nH inductor (and don't place C62) However, our WB schematics call for 1.0pF which sounds about right considering we are using a 22 nH inductor. High gain amplifiers have gates that are worked really hard to mimic a perfect switch and need to be tweeked for optimum efficiency so it doesn't really matter what we use in our WB since we are moving the frequency all over the place (that is the reason for the two VCO's)
R24 looks as if it is a compromise between using a 1.2 nH inductor and allowing RF thur.
Cheers
-
- Posts: 37
- Joined: Fri Jan 05, 2007 9:54 pm
PARTS while ASSEMBLING
Good, thank you very much !
The following is a live list of differences in my ongoing assembly (March 8th) which I would like feedback on:
------------
C4 I will use a 0.1 uF (as opposed to 1.0uF sch )
C2 using 100uF (as oppsed to 200uF sch)
L2 inductor will be the same as L3 (as opposed to images)
[these inductors have no polarity in datasheets so any orientation?]
The following is a live list of differences in my ongoing assembly (March 8th) which I would like feedback on:
------------
C4 I will use a 0.1 uF (as opposed to 1.0uF sch )
C2 using 100uF (as oppsed to 200uF sch)
L2 inductor will be the same as L3 (as opposed to images)
[these inductors have no polarity in datasheets so any orientation?]
Last edited by hahahehihoha on Fri Mar 09, 2007 2:24 am, edited 2 times in total.
- none_such
- Posts: 76
- Joined: Mon Jun 12, 2006 1:16 pm
don't make more work for yourself than necessary
just follow the schematics for placement and mind the RC1 revisions that you already know about.
Cheers
Cheers
Please be positive and constructive with your questions and comments.