This is an old revision of the document!
Unfortunately, there are many errors or discrepancies between the various resources available for this project. Eventually, they will all be listed here; if you can then update one of the resources (schematic, PCB layout, assembly directions), please do so and then remove the error from this list.
(extract info from thread, place on this page and remove thread from list:)
Omit parts R3, R4, R5 and Q2 on the LiPoly board; they are only needed to charge the battery if it falls below 3.7v, which it should not do.
Part | Incorrect | Correct | Remarks |
---|---|---|---|
C20 | 160pF, do not place | 390-550pF, placement recommended. | |
C36 | .47uF | do not place | part of (unused) noise circuit; do not place |
C40 | 68pF | ? | Sirenza datasheets say 1-2pF, not clear if this is an error or not |
C50 | ? | 1 uF 1206 | |
C51 | ? | .1 uF 1206 | |
C52 | ? | 1 uF 1206 | |
C53 | ? | .1 uF 1206 | |
C63 | ? | 1pF 0603 | |
C77 | ? | 4.7uF or 1uF, 0603 | Power supply filter cap; 4.7uF part is difficult to get in 0603, 1uF is ok |
C80 | 20pF | 22pF | Substitute to save money by combining order with other 22pF caps |
C81 | 20pF | 22pF | Substitute to save money by combining order with other 22pF caps |
C83 | ? | .1uF ? | not listed in instructions |
C84 | ? | .1uF ? | not listed in instructions |
D4 | 1N5235 | do not place | part of (unused) noise circuit; do not place |
IC2 | LM2733X | LM2731Y | Either part will work, but the 33X is not recommended for supplies less than 16v |
L1 | 15 uH | 7.3 uH | Only change if using LM2731Y |
L5 | ? | 1K resistor | |
L6 | ? | 1K resistor | |
R1 | 510K | ? | Pick a low-voltage point (e.g. 3.7v) – this voltage divider should |
R2 | 220K | ? | should output 1.1v at that point. Not currently implemented in firmware. |
R3 | ? | 39K | |
R4 | ? | 12K | |
R8 | ? | do not place | not usually necessary |
R9 | ? | do not place | not usually necessary |
R12 | ? | 100 ohms | not a critical value (instructions say 68 ohms) |
R13 | 100K | 63K | Value may vary to adjust VCO DC Offset gain |
R15 | 100K | 33K | Value may vary to adjust VCO DC Offset gain |
R19 | 2K | do not place | part of (unused) noise circuit; do not place |
R27 | 0 ohms | ferrite bead | |
R28 | 0 ohms | ferrite bead | |
R90 | 100K | do not place | part of (unused) noise circuit; do not place |
The silkscreened part numbers for the tiled Gerbers are incorrect; see http://www.ladyada.net/forums/viewtopic.php?t=4143 for more info.