Difference between revisions of "LMS-6 Radiosonde"
(→Connectors: I added some observations to the connectors from oscilloscope probing) |
(→Components: Some intel on U15.) |
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Line 111: | Line 111: | ||
|- | |- | ||
|2, 8, 18*, 24, 30 | |2, 8, 18*, 24, 30 | ||
− | | +5VDC | + | | +5VDC |
|18 needs more research, may occasionally drop to ground? | |18 needs more research, may occasionally drop to ground? | ||
|- | |- | ||
Line 136: | Line 136: | ||
|12 | |12 | ||
| | | | ||
− | |3.3v - 2.5KHz square wave (4msec p/p) | + | |3.3v - 2.5KHz square wave (4msec p/p) |
|- | |- | ||
|13 | |13 | ||
Line 279: | Line 279: | ||
U13 - [http://web.archive.org/web/20200214104034/http://www.ti.com/lit/ds/symlink/cd4040b.pdf CD4040BPW] | U13 - [http://web.archive.org/web/20200214104034/http://www.ti.com/lit/ds/symlink/cd4040b.pdf CD4040BPW] | ||
− | U14 - [http://web.archive.org/web/20200214042837/http://www.ti.com/lit/ds/symlink/cd74hc4051.pdf CD74HC4051PWR] | + | U14 - [http://web.archive.org/web/20200214042837/http://www.ti.com/lit/ds/symlink/cd74hc4051.pdf CD74HC4051PWR] |
+ | |||
+ | U15 - 92JK ZC5 (can't find much on this component) | ||
+ | [[File:Screenshot 20200904-195417.png|thumb|92JK ZC5 chip noted as U15]] | ||
+ | {| class="wikitable" | ||
+ | |+ | ||
+ | !U15 Pin | ||
+ | !Function | ||
+ | !Observations/Notes | ||
+ | |- | ||
+ | |1 | ||
+ | |GND | ||
+ | | | ||
+ | |- | ||
+ | |2 | ||
+ | |5VDC | ||
+ | | | ||
+ | |- | ||
+ | |3 | ||
+ | | | ||
+ | |Rounded square wave (maybe sawtooth) alternating between 2msec and 4msec, resting at +3VDC between bursts | ||
+ | |- | ||
+ | |4 | ||
+ | | | ||
+ | |Rounded square wave alternating between 3msec and 5msec, short periods of 0v, resting at +3VDC between bursts | ||
+ | |- | ||
+ | |5 | ||
+ | | | ||
+ | |Data. Square wave. 5V space, 0v mark? Pulses around 250msec per bit. | ||
+ | |- | ||
+ | |6 | ||
+ | | | ||
+ | |More rounded square wave bursts | ||
+ | |- | ||
+ | |7 | ||
+ | |5VDC | ||
+ | | | ||
+ | |- | ||
+ | |8 | ||
+ | |3.3VDC | ||
+ | | | ||
+ | |} | ||
+ | |||
U16 - [http://web.archive.org/web/20190417163532/https://www.ti.com/lit/ds/symlink/lmv761.pdf LMV761] | U16 - [http://web.archive.org/web/20190417163532/https://www.ti.com/lit/ds/symlink/lmv761.pdf LMV761] |
Revision as of 05:21, 5 September 2020
The LMS-6 Radiosonde is a radiosonde manufactured by Lockheed-Martin Sippican, and used for meteorological sounding.
Contents
Overview
There are two models of the LMS-6, a 403MHz model and a 1680MHz model. This article will cover the 403MHz model unless specified.
Specs
- 16 Fixed transmit carrier frequencies (MHz): 400.250, 400.625, 401.000, 401.375, 401.750, 402.125, 402.500, 402.875, 403.250, 403.625, 404.000, 404.375, 404.750, 405.125, 405.500, 405.875
- Frequency tolerance +/-30ppm
- Mean TX Power 70.8mW (18.5dBm)
- Emission Designator 16K8F1D
- FSK with a maximum modulating frequency of 4.8 kHz
- Emission 3dB BW +/-5.0 kHz
- Emission 20dB BW +/-12.7 kHz
- Omnidirectional antenna
- Main beam gain 2dBi
- Horizontal Beamwidth 360 degrees
- Vertical Beamwidth +84 degrees
Source: https://apps.fcc.gov/els/GetAtt.html?id=121623&x=.
Photos
Connectors
There are four sensor connectors (SENSN) used for sensor input by the radiosonde. SENS1 is not populated on the 403MHz units. SENS2-4 have leads connected to them, and the sensors are connected to the other end of the leads, outside of the radiosonde housing. Only SENS1 appears to have spacing for a connector; the others have arbitrary lead spacing.
Pin | Characteristics |
---|---|
1 | +5V (5.47 measured) |
2 | GND? |
3 | +4.93V (Microcontroller VCC?) |
4 | 1 Hz |
5 | 1 Hz |
6 | 1 Hz |
7 | GND? |
Public information shows this header can be used for adding additional analog sensors to the radiosonde.
Pin | Connection |
---|---|
1 | Sensor pin 1 |
2 | Sensor pin 2 |
0.3" spacing. Both lead wires have ferrite beads immediately before connecting to the board.
Pin | Connection |
---|---|
1 | Sensor pin 1 |
2 | Sensor pin 2 |
0.5" spacing.
Pin | Connection |
---|---|
1 | Sensor pin 1 |
2 | Sensor pin 2 |
0.3" spacing. Fine gauge insulated wire run along SENS3 wire and loomed in white heat-shrink tubing.
Pin Number | Function | Notes / Observations |
---|---|---|
1,2,7,8 | U3 - Vdd | U15 - Pin 4 | |
9, 10, 15, 16, 19, 20, 33, 34 | Ground | |
2, 8, 18*, 24, 30 | +5VDC | 18 needs more research, may occasionally drop to ground? |
3 | U3 - ICCLK | TP33 | U21 - PCLK | |
4 | U3 - Vpp/ICCSEL | |
5 | U3 - RESET | |
6 | U3 - ICCDATA | |
11 | J5 - Pin 2 | |
12 | 3.3v - 2.5KHz square wave (4msec p/p) | |
13 | U3 - SW1.4 | |
17 | U3 - SW1.2 | |
18 | U3 - SW1.1 | |
23 | Rounded-square wave data bursts | |
26 | Rounded-square wave data bursts | |
31 | BATT POS | |
36 | U3 - SW1.3 | |
38 | U3 - OCMP1_A / AIN10 / PF4 | Square wave data bursts, 0.2msec per bit |
39 | RED WIRE | |
40 | Battery voltage | Around 9VDC measured |
Pin | Wire Color | Use |
---|---|---|
1 | Black | Ground |
2 | White | Battery +9 |
3 | Red | +9 VDC In |
4 | NC | Unknown - goes to
unpopulated CR1 |
J4 - NC - earphone jack? uses SENS3 leads
Pin | Use |
---|---|
1 | Unknown |
2 | Unknown |
3 | Unknown |
4 | Unknown |
These traces go to U3 (ST microcontroller)
Pin | Use | Notes/Observations |
---|---|---|
1 | +5VDC | |
2 | Unknown | 3V rounded square pulses, 2x per second, 2 different periods avg ~75msec? |
3 | +5VDC | |
4 | Unknown | 5V, 0.1msec pulse once per second |
5 | +5VDC | |
6 | Unknown | 5V, 0.1msec pulse once per second |
7 | +5VDC | |
8 | Unknown | 3V, 250msec pulse once per second |
These traces go to U14 (SPI mem?)
Components
GPS - Trimble 63530-50 s/n 1190122906
https://www.trimble.com/embeddedsystems/copernicus2.aspx
U3 - 72F324J6T6 - ST72324 - Main Microcontroller, ST7 series
U5, U6 - LP2985
U?? - TPS7201Q
U13 - CD4040BPW
U14 - CD74HC4051PWR
U15 - 92JK ZC5 (can't find much on this component)
U15 Pin | Function | Observations/Notes |
---|---|---|
1 | GND | |
2 | 5VDC | |
3 | Rounded square wave (maybe sawtooth) alternating between 2msec and 4msec, resting at +3VDC between bursts | |
4 | Rounded square wave alternating between 3msec and 5msec, short periods of 0v, resting at +3VDC between bursts | |
5 | Data. Square wave. 5V space, 0v mark? Pulses around 250msec per bit. | |
6 | More rounded square wave bursts | |
7 | 5VDC | |
8 | 3.3VDC |
U16 - LMV761
U21 - TI/Chipcon CC1050 (TSSOP 24)
U22 - TPS791
Sens 4 - Capacitive Relative humidity sensor
Notes
U13 Package marking shows CM040B. TI Park marking lookup provides CD4040BPW
U16 Package marking shows C22A. TI Part marking lookup provides LMV761. The SOT-23 footprint appears to match what is on the PCB.
Sens 4 is know to be capacitive since it is listed as such on page 13 of the WMO Common Code Tables Document
Circuits
RF from CC to Ant1 - coming soon
Relative Humidity Circuit
File:Relative Humidity Circuit Schematic.pdf
U16 -Input also has a cap to ground not shown on the sketch.