V689U Chinese Digital Radio

I noticed the teaser for this radio on 409shop's website when I was looking up the current prices for the UV-3R radios. I've actually seen a different radio on Alibaba recently too but my inquiries are ignored or responded to by telling me that radio isn't ready yet.
According to these links:
http://www.brickolore.com/2013/03/409shop-teaser-v689u-digital-radio.html
http://www.brickolore.com/2013/03/v689u-kirisun-s760fp460.html
http://hamgear.wordpress.com/2013/03/13/chinese-digital-radios-theyre-here/
It's similar to, or it is actually this radio made by Kirisun:

http://en.kirisun.com/detail.aspx?id=61&zhu=1&Cyrus=1
I'm not sure though because the Frequency list here doesn't seem very useful for Amateur Radio needs. Another link that I've been to lists it as 400-470Mhz which would be useful and fairly standard actually for Chinese radios. It can do analog FM and digital modulation. All the details I can find on the digital is that it is 4FSK and it can create two 6.25Khz channels in a 12.5Khz frequency space which kinda sounds like TDMA?
It'd be cute if these were firmware reprogrammable and you could do codec2 on whatever chip is inside. I have a feeling it's the same old awful IMBE/AMBE type chips that you can only get through DVSI, like on D-Star. Of course this is coming from China, I guess it's possible they've reverse engineered those codecs and put them on a chip that can be reprogrammed to codec2 one day. That would make this radio more valuable. I just read on the hamgear link that they will be software updateable. So you can add more features, but no idea if that would include the codec or not. I'm guessing not, but we can always hope so.

Word is the pricing is going to be $200. A lot more expensive than other Chinese radios but you have the digital price premium to pay. (And the DVSI tax if it does use the DVSI chips)

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Baofeng UV-3R flashed

Lior is at it again, this time he's working on the Baofeng UV-3R radios. The MCU that runs the radio is flash programmable. Unfortunately the security bits are set so you can't read out the existing firmware first, but you can erase it and insert your own. A group is forming on the Yahoo Groups board to work on making a 100% community made firmware for these radios.
http://groups.yahoo.com/group/UV-3R/message/8141 This is the thread talking about the initial experiment. See this Youtube video:


http://groups.yahoo.com/group/UV-3R/message/8158 This is a thread where people are talking about what features they want to have in a community made firmware.
One thing to note, during the tests the PA circuits are turned off so it's outputting very low power. Too bad the radios are FM only, because that would be a good thing for transverters.. Hey, maybe it wouldn't be bad for the SHF stuff?
Could be good for fox hunts too.. Just flash it with a firmware to send the MCW occasionally and then hide it, no extra circuitry required.
These radios are pretty inexpensive at $41 each. I can well imagine quite a few things they could be used for if they are reprogrammed with a new firmware. Of course I have no illusions that the chip is powerful enough to do very complicated things. I am hoping this opens the door to a community who buys these radios for this purpose and then the companies respond to that by making more radios which can be flashed. Especially if they put more powerful chips in them and a few years down the road it's possible to flash codec2 onto one and have a very inexpensive digital radio.
I doubt that's possible with these. Maybe a 1200 baud packet firmware will come out though. Then you'd have a very inexpensive APRS tracker just by adding a GPS.

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Radio hacking: Baofeng UV-5R edition

http://groups.yahoo.com/group/baofeng_uv5r/message/20888
This rather industrious individual has been working on replacing the main CPU in his Baofeng UV-5R transceiver. These are cheap radios of course, but one of the neatest things is that they are cheap partly because they have a lot of functionality integrated. If I understand it correctly, there's a chip that basically handles everything for the radio functionality and then you have a CPU that controls the whole shebang over an SPI interface. The radio chip is an RDA1846.

The RDA1846 is a highly integrated single-chip transceiver for Walkie Talkie applications. It totally realizes the translation from RF carrier to voice in the RX path and from voice to RF carrier in the TX path, requiring only one micro controller.

The RDA1846 has a powerful digital signal processor, which makes it have optimum voice quality, flexible function options, and robust performance under varying reception conditions.

 Cut the power to the main mpu and that frees up the bus to communicate with the radio chip. In Lior's case, the SPI connection became damaged so he was able to enable I2C mode. He is using an Arduino so it actually works out to be easier to interface.


One neat thing he's already discovered is the ability to direct the RDA chip to produce sinewaves at any audio frequency and here his is demonstrating that by transmitting his callsign in morse code. According to him, 1200 baud FSK is even possible. That's just cool.

He has a page available here: http://www.liorelazary.com/index.php?option=com_content&view=article&id=49:hacking-the-baofeng-uv5r&catid=14:baofeng-uv5r&Itemid=17
This has more information and he may also work on the Baofeng UV3R at some point.

Incidentally in the discussion somehow a link to a bluetooth module was posted: http://dx.com/p/pcb-bluetooth-module-blue-140788 It'd be really neat to integrate a bluetooth module into something like this in order to use a cellphone bluetooth headset on a radio, but this one seems to be specifically for stereo bluetooth speakers. I wish someone would make a more universal module that could provide one or two or no serial profiles, one or two or no headset profiles, stereo profile, so on and then you could use whatever you needed in the project.

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Codec2, wifi and the future of Ham Radio

I've been keeping an eye on the progress of codec2 more recently. There's a modem and mode for using codec2 over the air now. FreeDV is a modem for Windows and Linux that lets you send codec2 voice in a 1.1khz bandwidth that can be sent over FM or SSB. The codec runs at 1400bps in this mode and has room for a callsign ID in the stream. Very neat!
I'm hoping sometime this year I can get one or two Raspberry Pi boards and configure it with one of the Debian distributions as a standalone codec2 digital radio, using standard 2m radios for the RF. Who knows, maybe I can use the GPIO pins with my reverse engineering work from last year to allow it to completely control my TM-241a radio.
Codec2 can, of course, be run at several other bitrates and other modems. Codec2.org suggests that a GMSK or C4FM modem might be developed for FM use.

Last year at the Hamvention a SDR based data radio was announced that could do up to 56K on 440mhz. UDR56K-4, KB9MWR has the press release. What I find interesting is that you could fit many streams of Codec2 audio over a 56K stream. What if you could get 2 pair of these modems, 2 inexpensive duplexers and then have a "wide" (for Ham Radio) bandwidth full-duplex link into a disaster area? You could have some bandwidth set aside for a dozen or more VOIP telephone links, compressed with codec2, for people to call out on. Meanwhile have bandwidth left over for emails, forms, graphics, you name it.

Another interesting thing that is going on are these little pocket sized wifi APs from China sold under the TP-Link name. You can find the TP703N for $20 on eBay practically any time. They have a port of openwrt, there are other devices available if you browse through that page. This particular one has 1 ethernet port, 1 usb port, 1 usb power in (5v 500ma) and of course built in wifi. Probably ideal for a HSMM-Mesh network. Thanks to the openwrt port, it should be possible to make these mesh nodes, or even more easily enough. I don't think they use the full 500ma so a small power source might be enough to keep one running for quite a while depending on what it is.

A lot of work has been put into smartphone technology in the commercial sector over the last decade, it'd be great if we could use some of that. A part15 wifi mesh would be nice in an emergency area. Non-hams could connect to it with their smartphones and get necessary information in several forms. Maybe apps could be developed which would let people send small messages, their GPS location or maybe a compressed picture to people who could use that information to direct personnel. As a part15 network, it wouldn't be necessary to worry about restricting who can use the network or if any traffic might pass over it that would violate part97 rules.

The FCC is trying to free up more spectrum for free wifi usage. http://motherboard.vice.com/blog/the-fcc-wants-to-blanket-the-country-in-free-wi-fi This article has the idea that they want to act as an ISP, but that's not what I understand. From what I understand they just want to open more spectrum up like the 2.4ghz and 5ghz bands for wifi. This is contingent on TV broadcasters giving up some of their spectrum instead. This means it would be much lower frequency (under 900mhz, above 440mhz) which should help the signals cover more distance. I have to wonder what this will eventually mean for the Ham world above 30mhz. Maybe someone will make a 2-way radio that runs on super-wifi?

There are the Ubiquity and other branded* 440mhz wifi modules as well but I have not heard any reports on those. They are not cheap by today's rates. I think they were >$100 per module and then you still had to have something to put them in.

*I can't remember what other manufacturer was making these now and my Internet searches are inconclusive tonight.

Stumbled across this article about Hams using wifi which posits a 2.4ghz digital wifi repeater with a 25mile range. I'm going to read more of it later but that could be interesting. Obviously using pricier equipment than the TP-Link stuff.

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TR-9000 frequency problem

Ran into a weird issue the other day on my TR-9000 when turning it on after a long time of being powered down. My band limits were set to 143.800-145.999. Seemed like the lower edge in the United States zone with the higher edge set to the Japan zone. Very weird. Found a PDF talking about mods on boxspringsonline.com though. One of which told how to modify the band limits and step size of the radio. Turns out, when power is applied to the radio, that is when it sets the limits. It's not when you turn the power switch on.

I had accidentally powered off my bench power supply when working in here one day for a short time. It must have been then when this funkiness happened. All I had to do to fix it was turn off the power supply and count out 5 seconds or so. Once I turned it back on and turned the radio on, I had the normal USA band limits of 143.800-148.995.

Don't ask me why that's the band limit. Every other radio I've ever owned has the usual 144-148Mhz. Obviously with those radios if you transmit right up against the limit you are going to have signal outside of the allowed frequencies. I guess Kenwood just trusted people to be honest?

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Packet Hailing Channel

Hailing frequencies open captain!


http://nwdigitalradio.com/products/

Kidding, good talk. Skip a few minutes in to avoid an intro. I was skeptical of the UDR56k when it was first announced. When you can get converted wifi modules that can do several megabits in Ham Radio bands, 56K seemed a little slow, and pricy. I guess compared to the common 1200 baud equipment, it's super-fast though. $400 has always seemed a bit much for me.

It's probably a good price though. I'm not sure what it costs to produce but it's probably what the market can bear and there are a fair number of Hams out there with big enough toy budgets to afford to buy these. At least they're not $1000 COUGHICOMCOUGH

eBay has a number of listings for wireless modules for Arduinos listed. There are NRF24 (2.4ghz) modules, and 2.4ghz bluetooth modules and modules based on the TI C1100 and similar chips that can do 440 or 900mhz bands for very inexpensive. Obviously it's a completely different purpose than something like the UDR56K. But could be interesting for some short range modes. I wouldn't be surprised to see an APRS mode one day.


http://www.aprs.org/aprs-rfid.html
This is a little old at this point but first I've heard of it.
Using RFID tags to beacon on APRS when participating hams are in areas with the proper equipment.
It could be handy to use to keep track of people inside of a large building, or see when people are in
the club radio station. Tags are really cheap and readers can be very cheap too. (At least, assuming
the readers I have seen for $10 are compatible with the tags you buy into)

I'll try to post other talks I find interesting. I seem to be getting hit with a deluge of them lately.

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TM-241a Remote Control commands

I made a pretty nifty discovery the other night. While I had zero luck trying to talk to my TM-241a with only my Bus Pirate... It can talk to it when I am piggybacking on the RC-10 I bought. There's one other variable here that I don't know if it changed anything or not... I updated the flash on the Bus Pirate since I was working on scanning for codes earlier in the year. I'm not entirely sure if the original firmware was running a serial clock on data out or not. That is absolutely essential for the radio to pay any attention to what you are saying.

Bus Pirate runs at 3.3v but can tolerate 5v logic, measurements seem to suggest to me that the radio uses 5v logic but then again, the measurements I've made were with the Bus Pirate and not a DMM.

Looks like the RC-10 brings RD (pin 6) to logic 1 (low) for about 250ms when the radio first turns on. I'm thinking that must be how it is telling the radio it is there. What I don't know is how the clock works. It doesn't run all the time, only when data is being sent or received. Also, when you adjust a control on the radio itself, it sends the data out on it's own. I'm thinking that the clock is run by whichever device has data to send. It also looks like the RC-10 sends 0xFF for each byte that the radio sends out. Maybe an acknowledgement signal of some sort?

Still working on the list of commands. Found a fair few sniffing the TX from the RC-10, but found even more after I separated those into groups and then sent the missing values from the groups. Seems like only 6 bits matter out of the bytes. There are two commands, VOL UP and VOL DWN, which use 2 bytes. 0x3C B0/0xBC 0xB0. I still haven't mastered these because they seem to continue to affect the volume after I send them. It either maxes out, or drops to 0. Only if the radio is told to use the remote unit's volume control instead of it's own. If it is, it's own volume control no longer does anything until a command is sent to re-enable it.

My progress is a bit hindered by the fact that my unit has the infamous LCD problem. It's full of garbled junk, and most of the time the elements are all faded out. Completely useless, but sometimes it works. Sometimes I can apply pressure and it works. I need to open it up and reseat the cable but I just haven't done it yet.

Ordered some parts on Ebay to make a sort of breakout box. Got some header pins, a jack that can accept a mic plug, and some other things like jumpers. I already have some perfboard with traces on it. I'll make it so I can plug my Bus Pirate into that and quickly disconnect the RC-10 to test things without it helping me. One of my major goals with this project is to make something standalone that can be used without a RC-10/RC-20 unit helping. It'll probably be a month before all of the stuff arrives though.

There are a couple of things I'd like to discover. I've found some things out already, and have a lot of buttons mapped but I can't completely replace direct control with an RC unit just yet. Some functions haven't been discovered yet. One other thing bugs me... When I first started working on this and didn't know what the protocol was I tried several other things with my Bus Pirate, one of which was I2C. Using the scan mode, I was hoping to discover if it was I2C and if so, what address. Somehow I accidentally overwrote the first couple memories in the radio with completely junk data. I may have blogged about that once actually, it's stuff that is impossible to enter in even with a keypad. I'm thinking there must be some mode to directly communicate and control the memory contents. I'd love to figure out how.

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