Have been looking at deploying a sensor network for a while now.
Live on land here. My desire is to deploy basic sensors around the block reporting conditions (temp, humidity..) and also to activate relays (water system) or actuators (chicken house door). They will need to be watertight and low power. This is not a surveillance network. Its a sensor network spread across 4ha. The sensors will be distributed across the area with 200m being the longest path.
I have looked at deploying sensors using wireless or Bluetooth but neither were suitable. Either would work but range limited and high power requirements.
Whilst reading Glenn VK3YY’s blog describing LoRa tracker I recognised the opportunity LoRa presented.
LoRa stands for Long Range. This is a wireless Radio frequency technology introduced by a company called Semtech. This technology can be used to transmit bi-directional information to long distance without consuming much power. This is designed for remote sensors which have to transmit its data by just operating on a small battery. The LoRaWAN® specification is for a Low Power, Wide Area (LPWA) networking protocol designed to wireless connect battery operated ‘things’ to the internet in regional, national or global networks, and targets key Internet of Things (IoT) requirements such as bi-directional communication, end-to-end security, mobility and localization services.
Intend to use the (433MHz) LoRa transceiver modules based on SX1268 chips from Semtech Corporation and LoRa protocol for the network layer of my sensor network.
Use of 433MHz is legal to use in Australia without any form of licensing up to 25mW. Also included on Amateur 70cm band 420 – 450 MHz. Primary Service is ‘RADIOLOCATION’ with Amateur as Secondary.
Difference between LoRa and LoRaWAN
- LoRa is the modulation technique used in the physical layer of LoRaWAN network. It is basically CSS (Chirp Spread Spectrum) modulation used to provide different data rates using different spreading factors.
- The basic principle is that information is encoded using chirp (a gradual increase or decrease in the frequency of the carrier wave over time).
- Before sending a message, the LoRa transmitter will send out a chirp signal to check that the band is free to send the message.
- Once the LoRa receiver has picked up the preamble chirp from the transmitter, the end of the preamble is signalled by the reverse chirp, which tells the LoRa transmitter that is it clear to begin transmission.
- LoRa contains only the link layer protocol.
- LoRaWAN includes the network layer RF, PHY, MAC and Application layer.
High level view
Here is my proposed private IOT network.
Sensors, actuators, gateways and servers.
The network will consists of sensors, actuators, gateways and servers.
- Sensors capture and transmit data to gateways over distances near and far, indoor and outdoor, with minimal power requirement.
- Sensors will be based on Arduino devices
- Sensors can be based on ESP32 devices.
- End-nodes, or sensor devices will use LoRa Modulation (LoRa Technology) as the physical (PHY) silicon layer to create the long-range communication links
- There is a wide range of input options
- BME280 – temperature, humidity and atmospheric pressure sensor.
- CC811 – CO2 and TVOC (total volatile organic compounds) sensor.
- SDS011 – Dust sensor (particulate matter – PM 2.5 and PM 10).
- MQ135 – Gas sensor. Has high sensitivity to Ammonia, Sulfide and Benze steam, also sensitive to smoke and other harmful gases.
- AS3935 – Franklin lightning sensor (voltage divider)
- https://create.arduino.cc/projecthub/projects/tags/sensor …..
- Output will be relays or actuators depending on use. A relay can switch a water Solenoid whilst an actuator could close a chicken house door.
2. LoRa Gateway:
- Gateways send information via Wi-Fi to devices on the TCP/IP Ethernet network.
- Gateways will receive and send LoRa Technology
- Arduino compatible device.
3. Application Servers & Cloud IoT Services:
Applications interpret the data collected by LoRa devices. Not sending into Cloud Services initially. Will send APRS WX from external sensors once sorted.
The application server in this case will be a device salvaged from a dumpster running Linux hosting a MySQL database displaying the information via Apache (LAMP Stack).
The sensor nodes will be based on Arduino,ESP32 and ASR605x (ASR6501, ASR6502) controllers.
The LoRa gateway will be based on Heltec micro controller.
This device is supported by Arduino GUI and has onboard OLED, WFIF and LoRa. There is also battery management abilities.
- WiFi LoRa 32 (V2) from Heltec Automation
- Microcontroller ESP32 @ 240MHz
- WiFi WIFI802.11 b/g/n/e/i
- LoRa chip SX1278
- Bluetooth BLE
- Flash 8MB
- RAM 320KB
- Display 0.96 inch 128*64 OLED
- Fully supported by Arduino IDE
- Lithium: Battery socket for Heltec boards is SH1.25-2 (JST 2P-1.25 (JST connector with 2 pins, separated each other by 1.25mm)
- Vext 3.3V(500mA) output, for external devices (e.g. sensors) power supply, in deep sleep mode, Vext can be shut down via software
- $30AUD delivered
Anyway so off I went.
Ordered some BME280 sensors and a couple of the CubeCell dev boards. The intent is to deploy outside. This setup will be able to run off a 18650 3.7V 1200mAH lithium polymer Battery.
Started to program with the devices and sensors I have here. Had all-ready ordered a WiFi LoRa 32. The built in Display, WiFI and Lora interfaces for $20 was too hard to pass.
This data is not going to any cloud IoT services. Ultimately will expand to exploit select IOT cloud services but intent is to keep it internal.
I’ve used JSON ‘encoding’ for data being sent. There are a lot of reasons not to use JSON. Im using JSON to support device IDs.
LoRaWAN provides headers that support device identification. Had a go at Cayenne Low Power Payload (Cayenne LPP) encoding. Worked as described in the tutorials. It is used as payload for the TTN so a lot of material around. For now I did not want the overhead of LoRaWAN just for device ID so using JSON for the payload and adding own device control. Yes JSON is fat. Same data is 21 bytes using Cayenne whilst JSON comes in at 65 bytes.
When it comes time to send to IoT services it will be straight forward to pass the JSON to Cayenne then to via LoRaWAN to said service.
The use of JSON is also consistent with conditions of the Amateur licence. Not encrypted, clear text. No privacy concerns with clear text out here. Remote private network broadcasting current conditions in clear text. Dare say of little interest to Mr Potato Head.
Typical Data Packet;
Also the size of the JSON data in bytes for the JSON string and RSSI from the gateways point of view are sent.
Decided not to use the Heltac library, not because it was not enticing but wanted to ensure compatibility across wider devices so open libraries used. Used the LoRa library from Sandeep Mistry. The Heltec library is identical
HTTP GET to PHP script on Centos server. Not happy with using GET. Again based on the Heltec examples as it worked.
PHP used for the script on the LAMP server to store the data in a MYSQL database. Based on existing routines and works well. No presentation layer. Just working routines for now.
So currently (8 Mar 2020) Two sensors are sending data.
Here are the contents of two tables;
So the basic functionality is present however, the gateway hangs after a couple of hours use. Suspect I have a buffer over run. Currently checking code as suspect its my error. I have Mega 2650 Mini available so will order another couple of SX1278 boards and create a gateway to see if its a hardware issue
I’ll go into detail of each step and link pages here;
- Arduino Sensor Sender
- WiFi LoRa 32 (V2) LoRa Gateway
- Centos LAMP Application Server
- Interfacing SX1278 (Ra-02) LORA Module with Arduino
- Mozilla WebThings PHP IOT Framework
- WiFi LoRa 32 (ESP32) TTN
- VK3YY Tracker
- G6EJD ESP32 voltage reading function
- Battery Level Sketch
or dumpster diving for computers.
I’ve noticed a trend. At the end of university terms the skip bins around student accommodation fill up with fridges, lounges and computers.
I’m putting this down to the the high cost for freight and low cost of technology.
Its not like I don’t have enough computers. In the shed there is an Apple IIe Clone, varies 8080 -> Pentium based devices (IBM XT & AT339) and collection of RISC (ultra 2, SS2,10 & 20, HP and a dual CPU DEC Alpha) devices.
They all worked before being put away. Doubt they would boot up without addressing NVRAM issues and the odd wasp nest but they are going nowhere. Well that’s debatable as whilst the cases and boards may stay in my shed their souls will be reward in Silicon Heaven.
I use a Apple Mac for my desktop (the 27’ 5K iMac screen soothes old eyes) and for my personal notebook. There is a Dell notebook with Windows XP and a serial port for programming radios and everything else runs Linux.
I rarely purchase new. The Macs come from Apple refurbished site and if I need components, eBay is the first port of call. Anyway I have recently acquired two computers by not being too ashamed to jump into a skip bin.
MSI 7688v1.0(G52-76881X1)(P55A Fuzion). i5 CPU 760 @ 2.80GHz with 8GB memory.
Walking home down Collins St noticed a skip bin with the results of an office refurb. Hidden between the discarded partitions and lighting there were several computers cases, LCD screens and a printer. Seriously ? computers are considered office waste now ? Ok going in….
I was not alone and had to act fast. These computers had attracted the attention of another ‘recycler’ and we worked together. He took two boxes and a screen whilst I only grabbed a single box, did retrieved memory from one of the other boxes and just made it to the train heading home.
Knew it was a intel based device due to the sticker on the fan and assuming later then a Pentium based device as no ‘Intel inside stickers’. It was a long ride home wondering if I was bringing someone else’s rubbish home or had hit silicon jackpot. Michele is very tolerant but we don’t need another ancient device in the shed. Got home and ran it up to setup as no HDD. The case was low end and missing feet but did have a power supply. Also has a NVIDIA GT216 PCI-E video. The mother board supports Multi-GPU Computing. Ok that sounds cool so lets get another card tomorrow. Went back to the skip bin on the way to work on the next day armed with screwdrivers and pliers to retrieve more memory and a second video card but there was only had plaster and cables left. Too late.
Sourced a tower case and HDD. Installed Linux Fedora 29 and configured as a LAMP box so now it is hosting test instance of the ParksnPeaks website. This use to be hosted on the HP8100 but ran out of space and unable to add another drive.
The HP 8100 was sourced second hand from eBay. It has a 2TB drive and runs Ubuntu 16.04.5 LTS hosting AppleTalk as it is the backup target for our Macs. The idea here is to pick it up one computer when leaving for fires so whilst you may loose hardware, will have data.
Dual Xeon Server
Intel® S5500BC Server. Dual Xeon(R) CPU E5506 @ 2.13GHz with 16GB memory.
Walking back from lunch recently I noticed a tower sitting next to a skip bin. It had empty slots where HDD carriers had been removed. You could see two heatsinks. This device caught my interest but I had to leave it as the case was too big to take back to work. I was receiving enough ribbing from by lunch buddies all-ready so stashed the case behind the bin to and took the ribbing whilst walking back to office.
So once back at the office and out of sight of my ‘friends’ I grabbed a Phillips head and went back to see what was under the heat sinks. Took off the heatsink and rubbed back the compound to find an Intel Xeon processor. Half the memory banks were filled. There where no hard disks nor a power supply so decided to take the board leaving the case in the bin.
Got a case out of the shed and ran her up. She booted to setup no issues. I took a photo and sent to those who doubted it just to prove I’m not just a nutter, but a nutter with a dual Xeon server. Added a HDD and installed CentOS Linux. Setup up a search for ECC memory and picked up additional 16G from the US for $77 delivered. Now all the memory slots are filled, just need a decent case. The device is a SSI CEB form factor – 305 X 276mm slightly larger than a ATX 305 X 244 mm so a slight challenge as don’t want to buy (or pay for) a server case. Here she is running. Notice doing nothing.
So what am I going to do with them ?
None of the devices are doing any real work. Need a box for testing and backup.
The inner accountant says should do nothing and keep using the HP8100 as backup and dev box. It requires no new hardware and uses the least energy.
The inner geek says not to listen to that idiot. If he had his way you would have been eating lunch at your desk not enjoying luksa and there would be a dual xeon server in land fill now.
So have got my eye on a case for the Xeon. Will add a couple of drives for backup target and use it as the dev / test box going forward.
Want to add some devices outside for sensors and to automate garden activities. Glenn VK3YY raised the opportunities LoRaWAN present so intend to work out how to build a mesh of small devices reporting to the server using 70cm band. Will need a device to host a database and process all the data that will be generated and this would be a honourable task for such a device.
Recently acquired a unbuilt ATS4b kit.
This is a miniature 5 band CW radio. A KD1JV kit. It is small, lightweight, and fairly rugged HF QRP Radio. It uses very little current on receive and is efficient on transmit.
- 80, 40, 30, 20 and 15/17 meter operation
- LCD display with back lighting
- DDS VFO for wide tuning range with crystal stability, 50 Hz tuning steps.
- Single step or auto increment tuning
- Sensitive, 0.2 uV receiver with very low internal noise for exceptional S/N ratio.
- Selective CW filter with 4 crystal IF filter and audio band pass filter
- 7 to 12 volt supply supporting;
- 4.5 to 5 Watt transmitter output on all bands (with 12 volt supply)
- 2.5 watts output typical with 9 volt supply
- 50 ma no signal receive current
- 680 ma maximum transmit current at 12 volts
- Small size, 12.5cm wide, 6.8cm deep, 2.5cm tall
- Light weight, 178G.
This is a SOTA radio.
This kit was released 2011 so lucky to get my hands on one (Thanks Tyler and Bill). You can purchase an assembled similar radio being a LNR MTR4B (80,40,30 & 20) at 400US$ + freight. Given the declining AUD (thanks mining why does the need for foreign owned enities to profit override my desire to play radio ?) it really has not been high on my list to purchase one. I jumped at the kit. This device supports 80m.
Have a mate in the US (Thanks Jason) and he was happy to receive and send on to me so ended up landing here at around $400AUD inc freight.
This is a part of the quest to reduct weight so as to pickup some of the more challenging summits. Whilst are not a long walk they will be a big effort given the terrain and conditions. This device will keep the radio and antenna equipment well under 1Kg and support 5 bands be it CW only.
Reluctant to go out without 80m. For the chasers as much as to ensure enough contacts to qualify. Not having issues getting CW contacts these days.
Had spent the morning soldering copper tubing for fire sprinkler system. This is using the gas torch, liquid flux and 3mm solder. The afternoon was to be different. Once it started to rain (the geese were happy) I decided to come in and get out of the mud and cook up a radio.
This kit contains SMD components. Previous build of SMD based device was a KD1JV MTR v2. This went well with the only real issue being as a result of losing a component and replacing with the wrong type.During the build, you have to choose between 17m or 15m. I will go for 15m.
Having read the manual and check the parts it was time to start assembly. This is not a task to rush into but rather progress in an orderly manner.
First step is to add the IC’s. Decided to hand solder these as a single task as the idea of placing all the semiconductors, capacitors and resistors then melting the solder in one sitting did not sound like a good idea.
At end of day one I had the IC’s on ready to inspect. Completed page 15 of the manual.
Day Two. Testing the rework device.
Was not filled with desire to start heating up the board yesterday. Decided to verify the hot air soldering process before going forward. Using Solder Paste from Jaycar which has the Chemtools ID on it. Found the spec sheet on Chemtools website.
Yes using leaded solder. Have had trouble with using unleaded solder and think by now I have enough lead in my system given the paint used when a kid and the years of soldering not to get too worried about it.
Didn’t trust the 852d+ soldering rework station so checked the temp and tested with an old board from the shed. Yes the display was out so experimented until in the range and able to take caps off the S3 board and solder them back on in a timely manner. All good.
So think I’ve procrastinated enough so time to commit to melting solder, tomorrow caps ….
Day Three. Check and Check again.
Zoomed in on some components with a 2MP USB microscope from eBay checking.
Upgraded the lights above the table but basically my eyes are not what they use to be so need such a tool. Not the absolute answer but these microscopes are worth the $A30.
Mixed results. The microscope stand had to be extended to get a good view. It did expose issues (surprising number of joints that were missed) and they were addressed. Once checked and addressed went back with magnifying glass and checked again. If this was left it would manifest as failure in the field so keen to fix now.
Day Four. Capacitors Bottom Side.
Capacitors went on well. So will check the board again to be sure.
Day Five. Through Hole Components.
Not consecutive process as well work and we went Wuthering Saturday. Checkout the video, thats us in the red to the left !
The SMD parts went well. Very happy with the result. Working through the through hole components now.
Wet and windy weekend to was able to continue work on assembly Sunday. I have been following the instructions carefully as aware may not get such a kit again and that components may not be available should I loose or break some.
Adding the Low Pass filters (Page 20 in the assembly manual), which states that “These all go onto the Bottom Side of the board” whilst the picture on same page shows C73,C74 and C75 mounted from the top. I soldered C74 was per the instructions and whilst checking noted the discrepancy created by the picture. Removed C74 and placed in on the top of the board as per the picture. This caused conflict in my head and went checking out pictures on the web and which show them mounted on the the bottom.
See no reason to tempt fate de-soldering and moving C74 again so leaving as is on the top. Also have enlarged the hole to support a BNC connector for the antenna. Files the hole so it was slightly higher so as avoid the board. As you can from a dry run it will fit without causing grief.
Working through the toroids now, again carefully and without time constrains.
Day Six. Final Assembly.
Well actually 10 days in total but have to go to work and other things….
After winding and installing the toroids its a case of assembling the hardware and connectors.
She did not come up on the first test and this was quickly traced back to a faulty 9V battery connection. Found another in my sons junk box and away it went.
From here it worked as described. The DDS came up on 10Mhz exactly.
Outputting 2w on the 40 – 15M 9V with 80M around half that. I took note of the torrid winding (loose for even and tight for odd) but there is not a lot of room to move for L12 & L14.
Connected to the home antenna and turned the receive to peak noise.
The unit is operating so ready to take out onto a summit.
I see no value in disassembling and trying to refine the windings on 80M. Ok yes did chase this device for 80M but its a fall back frequency. Let’s get out on a summit and see how it works before playing with the number of turns.
Another Arduino basd project, well not quite. The Arduino Uno is a microcontroller board based on the ATmega328P. This kit from QRPLabs also uses the ATmega328P. The software is not open source. Updates are provided as hex files.
This kit is extremely well documented. It is worth buying and assembling just for the documentation.
The assembly instructions are very clear and contain operation theory and alignment process.
Once assembled the device would not start. According to the excellent troubleshooting doc the processor had not been reset.
I had performed the modification for reliable microcontroller startup (repurposing inductor L5) during assembly so turned to the troubleshooting manual for direction. First was to go back and check components then touched up the soldering around the processor and crystal and she started Ok.
Next was to follow the assembly manual and align / tune then update the firmware. Again wth the excellent instructions there were no issue here.
Update Firmware from Mac;
I’m going to update the firmware from Mac using avrdude.
Purchased a USBAsp AVR programmer locally. It has a 10pin connector so get a 10 to 6 to match the ISP interface on the QCX or use dupont connectors like I did.
There are instructions on the QRPLabs site for win process for using but No I want to use my Mac. Again Google is your friend. Given allready have XCode installed, I decided to just install avrdude and use the command line.
Process is straight forward.
Open a terminal session and install Homebrew;
ruby -e “$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)” < /dev/null 2> /dev/null
Then install avrdude;
brew install avrdude
So the software is installed.
First Plug in the USBASP and verify the computer can see it (About->System Report) then check avrdude can see the QCX;
Allens-Air:QRPLabs allen$ avrdude -c usbasp -p atmega328p
avrdude: warning: cannot set sck period. please check for usbasp firmware update.avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.00s
avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: safemode: Fuses OK (E:FC, H:D1, L:F7)
avrdude done. Thank you.
Noting the warning message. A quick Google revealed this is not an issue and there is a parameter you can pass to avrdude to skip skip the check so not worried, Ok then lets flash the device;
Allens-Air:QRPLabs allen$ avrdude -c usbasp -p ATmega328P -U flash:w:T1.00f.hex
avrdude: warning: cannot set sck period. please check for usbasp firmware update.avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.00s
avrdude: Device signature = 0x1e950f (probably m328p)avrdude: NOTE: “flash” memory has been specified, an erase cycle will be performed To disable this feature, specify the -D option.avrdude: erasing chipavrdude: warning: cannot set sck period. please check for usbasp firmware update.avrdude: reading input file “T1.00f.hex”avrdude: input file T1.00f.hex auto detected as Intel Hexavrdude: writing flash (32076 bytes):
Writing | ################################################## | 100% 21.78s
avrdude: 32076 bytes of flash writtenavrdude: verifying flash memory against T1.00f.hex:avrdude: load data flash data from input file T1.00f.hex:avrdude: input file T1.00f.hex auto detected as Intel Hexavrdude: input file T1.00f.hex contains 32076 bytesavrdude: reading on-chip flash data:
Reading | ################################################## | 100% 16.32s
avrdude: verifying …avrdude: 32076 bytes of flash verified
avrdude: safemode: Fuses OK (E:FC, H:D1, L:F7)
avrdude done. Thank you.
thats it done ! Now running version 1.00f.
From here I intend to go through the troubleshooting instructions with my new oscilloscope and explore the device.
Another Arduino based project. This time an W8TEE and K2ZIA Antenna Analyzer.
Purchased the PCB from https://qrpguys.com/w8tee-k2zia-antenna-analyzer
Not a kit so sourced the components. Easy to order from china off eBay. Took about 2 weeks for all the bits to come in.
Assembled and she started but the SWR for a 51ohm dummy load was off the scale.
The audrino and screen are ok. Checked and double checked solder joints so needed to verify the DDS and SWR bridge operations.
My old Dick Smith device is not cutting the mustard so borrowed an oscilloscope from Lacky VK3ALM. Traced the signal into the SWR bridge and nothing out. Checked the components and well my bad as the 51ohm resistors were in-fact 51K ohm. Bit of a difference. Replaced and off she went !
Downloaded the latest WA2FZW software from IOGroups – https://groups.io/g/SoftwareControlledHamRadio/files/Improved%20Analyzer%20Software
The documentation and a debugging guide are available from this group, essential information.
Use a case from radio parts (CB8808). Yes there is a pimple in the middle. No intention to remove as works fine.
So far have scanned all my antennas at home. I can recommend this device. Not a kit but the process to source and assemble was fun.
04082018 – VK3/VC-024
Went to Mt Beckworth for the VK1 S2S Party.
Third attempt to activate Mt Beckworth this year, first failed as the KX3 battery was flat and didn’t take a spare up to the site, second was changed to Mt Bunnyioung as slept through the alarm. Made it this time
This is a good site for such activities as close and clear.
QRPGuys 20/30/40 vertical with an additional 6 ground wires making 9 in total.
It is hard to pick differences without actually running all the antenna up at the same time, but a much better response with the additional ground over the original 3 wires when deployed at Mt Bunnyioung recently.
Didn’t run the end fed out to gain 80m as comfortably qualified and the other sites ended on on these bands.
This was also a run with the new ‘Compact heavy-duty 7 m mast from SOTABeams’. As you can see the mast nearly fits into my backpack.
This will be great as now will not be harassed when hiking through dense bush (still not returning to Hells Gate !) Bit heaver but figure I just need to get fitter.
Good activation with 15 S2S in the fog. Also 1mm rain but not complaining about that given the drought in NSW.
anyway, great activation. Ready for VK JA ZL – EU S2S QSO Party Saturday 20 October 2018 – 06:30 UTC to 08:30 UTC (Melbourne, Australia*AEDT (UTC +11) Sat, 20 Oct 2018 5:30 pm)
HF SIGNALS started shipping the μBITX boards (or micro BITX) December 2017. This is a a fully wide-band 3 to 30 MHz transceiver with upper and lower sideband and CW, power up to 10 watts and solid digital control. The circuit boards come wired and tested and with all the hardware. An interesting component of this radio is the Radino. This board has a Arduino Nano controller and a Si5351 for all local oscillators.
Radio Description – http://www.hfsignals.com/index.php/ubitx-circuit-description/
uBITX Net – great source of uBITX information.
groups.io has a group for the varies BITX projects.
I chose not to use the plastic case that it came with or to print a 3D but instead purchased an universal enclosure from Amateur Radio Kits (INKITS). It took 6 weeks deliver, which was not unexpected. These things take time and worth the wait, The case is excellent value. Metal and came with additional installation hardware including PCBs for the external connections.
uBITx wiring – http://www.hfsignals.com/index.php/ubitx-wire-up/
uBITX Net has a list of updates to make.
- The case included a power board and fuse which addressed the reverse polarity issues.
- KD8CEC firmware upgrade described below
- My board has a FCI audio chip so no action there
- Header connectors available from Jaycar for the leads
Initial build photo below. Have added additional wiring for ground issues and wired in USB interface. Will get a photo next time case off. Will be soon enough
Digital to the Left, Analogue to the right. Pin 1 to the left
Update – VU3SUA case documentation – https://ubitx.net/2018/08/03/vu3sua-case-documentation/
Used the front panel board that came with the case. Proved to be convient and tidy but still not without its challenges. You will need to follow Sunil Lakhani on facebook to gain pictures of the boards, assembly tips and info for the board
The encoder is not straight through.
1<->1,2 <-> 4,3<-> 3, 4 <-> 2
You need to add two resistors to support a CW paddle. Follow the directions on uBit.net.
Worked as advertised. Again checkout ubitx.net – http://ubitx.net/compare-software-options/
Decided to go with KD8CEC firmware – http://ubitx.net/wp-content/uploads/2018/04/ug1072_087.pdf
Get the latest from https://github.com/phdlee/ubitx.
Download the firmware files from GitHub, compile and upload to the Radino.
Bingo so now you have a HF full source code for the HF transceiver on your computer. That is cool in initself.
I ended up running version 1.08. Manual – http://ubitx.net/manual-kd8cec-firmware/
The board is v3. I want to address the T/R click noise and add an CW Audio Filter. Also saw pcbs for filters based on Glenn VK3IL’s blog.
Nick VK4PLN uBITX Add-On boards – https://vk4pln.blogspot.com/2018/03/vk4pln-ubitx-add-on-boards.html
Calibration of these devices appears to be a black art;
Deployed common ground via a star config which improved the audio however still have the noise when using the speaker.
Current solution is to stick to headphones and use the device.
Updated the pic to show grounding. The brown wire goes to the common on front panel board. Still noisy.
This is a fun radio.It’s cheap, it works and requires very little skills to get operational.
Think will source another board. The uBitX v4 boards have no Audio IC On the board.
26.5m 80/40/20/10 EFRW
Went with 49:1 on a FT82-43 toriod with 3:24 ratio and a 120pf 500v mica cap (that was what I had) with 26.5M of wire.
Intentionally selected a length with no half waves. 26.5 m = 87 feet. (https://udel.edu/~mm/ham/randomWire/)
http://www.qrpkits.com/sota.html with 19.5 m wire and counterpoise
Trap 20/40 Dipole based on SOTABeams pico traps – https://www.sotabeams.co.uk/pico-traps-kit-pair/
Trapped end feed also based on pico traps.
QRPGuys Portable Tri-Band Vertical Antenna – https://qrpguys.com/qrpguys-tri-band-portable-vertical-antenna
Looking for a DX antenna for S2S evenings. A 20m vertical appears to be the answer.
This will rock for 20 and 30 but doubt 40 will be much chop.
Got the switches 2m off the ground.
Had to keep the forth radial as it reduced swr, actually it flattened it. So three radials one down each guy and the forth just hanging down. Actually except you need the squid pole its quite a compact sturdy antenna.
Spreed the anti with clear acrylic
Tuned each segment with the VK5JST tuner. Also ordered the W8TEE and K2ZIA Antenna Analyzer – https://qrpguys.com/w8tee-k2zia-antenna-analyzer
20082017 – VK3/VC-018 Mt Bunnyiong
VK1 SOTA activation day and a test run for miniHFPA HF Packer Amp.
Noticed the alerts going up for VK1 2017 Winter SOTA Party so decided to go to local summit to play SOTA one what looked like a reasonable day to go out. Propagation recently has been terrible for NVIS so decided it was time to test my newest toy, a miniHFPA HF Packer Amp. This is a 35 watt linear amplifier designed for portable operations.
Decided to a to build a lightweight amplifier that can be backpacked to sites and be powered by a light weight LIPO 3S battery. Did look at commercial options. There are several out there a assembled Chinese unit and there are several kits available from eBay but appeared not to have adequate filters and lacking harmonic suppression. Glenn VK3YY describes building a unit based on W6JLs designs. There are a lot of kits around which would be more accurately described as harmonic generators.
I went for the HF Packer kit. I have decided to build as much as I can and not being a electronics engineer more that happy to assemble kits. The new 35w kit was announced and I put my name down for a unit. Not the cheapest options but was expecting a unit that was well designed and meet the conditions of my licence
The build went well. The biggest issue I had was using unleaded solder. My fixed temp iron was not hot enough. A new variable iron fixed the issue and the build progressed. Once completed had issues completing the testing process. The issue came down to incorrect marking of the RF ports. Once addressed (Thanks David) the device leapt into action.
So going from 5w to 35w output is a gain of 8.45dB. Given 6dB is a S point expecting an additional 2 sS points for my signal reports. VK7CW and VK2YW gave me a 599 with the amp in use.Off top a great start. Later without the amp in use I received a 559 from VK2WP. None of the contacts were soliciting reports as my CW is only good for making contacts not setting up experiments. Pre roll over SSB contact with VK1CT received 59 and post received 45. No one described poor signal so very happy with results.
At 717grams it won’t be a frequent addition to SOTA activations but when conditions are not good and the trek supports the additional unit and battery 35W it will be available.
The 4500mAh 3S 30C LIPO was at 80% after hour of use. Time for new batteries so will be going for a 2500/3000 mAh unit.
So the next is to develop a suitable antenna. Used a trapped 20/40 unit based on SOTABeams 100w traps for this activation.This unit is too heavy for SOTA however so looking at options.The AMP is rated at 35W for 60/40 & 30/20m bands. Will need a resonate antenna to avoid carrying a tuner so looking at a EFHW (End Fed Half Wave) instance. There is a lot of information out there. David VK3IL page describes a similar quest he went on and a search of the SOTA forum search pointed me towards HB9TVK. Thinking of using T80-6 for traps and a T140-43 for the matching transformer, RG178 coax and lightweight wire. Yes looking at grams here and the trap weight has to be trimmed else the wire will sag too much and can’t be seen on a summit with a sagging antenna!
More on antenna as options are finalised. Also will be building a CW radio for wet harsh conditions. Ordered the QRP-Labs single-band 5W CW transceiver kit and will build into a waterproof case.
160 to 6m Endfed for Portable deployment.
This is a big antenna and will not be suitable for tight summits. However ideal for Alpine summits.
135 feet or more then 42m appears to be the go.
7M squid pole holding top at 7m. Yellow cord to keep tips 2m off ground.
guy on squid pole
RF choke on RG174. 8 turns so can use 10m shield as counterpoise.Ends held in place with cable ties then covered in heat shrink tubing.
End Fed – http://vk6ysf.com/longwire_antenna.htm
VK6YSF 9:1UNUN http://vk6ysf.com/unun_9-1_v2.htm
Emergency Amateur Radio Club of Hawaii (EARCHI) 40m to 6m Endfed antenna using a 9:1 match. It consists of 30ft (10m) of wire fed into a 9:1 UnUn (Unbalanced to Unbalanced).Plans for the Antenna are available from EARCHI’s website
Counterpoise lengths appear to be quarter the lowest band so for 160m will be 40m. The ideal radiator length is one that avoid harmonic multiples (1/4 or 1/2) of the operating frequencies. Why is this not a dipole ? High impedance to support multi band operations. Here are the sites that describe the radiator lengths;