I am new here and excited to get into this area of communications.

An idea struck me the other day. We live in an area of mountains with not a lot of line of site for connections. So I got to thinking is there any way to take the signal from the router and sending it through a cheap Chinese radio 2 meter or 440 radio to relay the signal to a router set up the same way. These radios are so cheap now that I wondered if anyone has tried to hack this together.

Thanks for any input.

No.

(Sorry, couldn't resist.)

Seriously, there just isn't enough bandwidth available on 2M/440 to squeeze any serious throughput in. The 2.4 Ghz wifi channel is 20 Mhz wide, much wider than the 25 Khz available on the lower bands. If you rummage around the forums, you'll find some links to a couple of companies developing narrow band radios with decent throughputs, but 'decent' means slow dial-up. Better than 9600b packet, but you probably won't be doing video conferencing. I've worked with radios commercially that can reliably do 96k kb (kilo- bits, not bytes) in a 25 Khz channel, but they aren't cheap.

I've got a similar situation; I don't live around mountains, but I do live in a hole. I'd need an 80' tower to get a clear line of site anywhere. I'm pretty much stuck with mobile operations from my car. If you can get something up on a nearby mountaintop, however, you'll be surprised at the performance you can squeeze out of these little routers.

Good luck, and have fun.

Yes.

(Sorry, couldnt resist )

But not the way you describe.

We can run spread spectrum on 70cm @ 10 watts PEP.

In theory at least, we should be able to run White Space radios on 70 cm. I also hear that a Japanese company has sold a 70cm-specific 802.11 radio. If they are available in miniPCI or USB form, such a radio could easily be run in an OpenWRT node. Embeddable backplanes with miniPCI are very popular node hardware with the WISPs and certain ones will run OpenWRT distros. And lots of folks have hacked a USB onto a Linksys box.

A quick search found this:

http://www.carlsonwireless.com/products/ruralconnect-ip.html

and this:

http://www.wirelessinteractive.com/orion400/

These are complete commercial systems with an embedded router, antenna etc but at heart they have an Atheros card of some kind (someone will have parts to sell). These run above 460. But there are always hacks....

UPDATE:

This link is a fairly targeted and names names....

http://www.3dbwireless.com/boyd/?p=466

Cheers;

Bob KV4PC

https://www.xagyl.com/store_ca/product.php?productid=16450&cat=327&page=1

Here is a 1 watt 70 cm radio WIFI card.

Another 70 cm radio: http://doodlelabs.com/products/sub-ghz-range/420-450-mhz-band-dl435.html

Oddly, these guys clearly state this radio is intended for Amateur Radio service, yet advertise 128 bit AES encryption "for over the air privacy".

Also oddly, they claim to only want to work with OEMs. Anyone know of a company making commercial ham nodes for 70 cm? Heh... want to start one?

Cheers;

Bob KV4PC

http://nwdigitalradio.com/ is making a 70cm digital radio, coming soon.

@KD7RYY

WIFI = IEEE 802.11a/b/g/n MAC, PHY, waveform.

While a 56 kbps radio is of general interest to most anyone playing with digital modes it is not very closely related to "BroadbandHamnet", being simply a "pretty quick packet radio". You can run TCP/IP over any bidirectional serial link. You can also mesh pretty much anything that involves TCP/IP with the right routers. However 56kbps is no where near the data rate required by "high speed multimedia". You would be hard pressed to do one channel of VoIP over a solid 56k link.

Im not belittling it - 56k packet has been a long time coming and it has a well defined place in the world of Amateur Radio. But it is part of a different "food chain" so to speak.

The radios I posted are 1 Mbps to 54 Mbps 802.11b/g mini-PCI radios that produce several WIFI channels on 70 cm. They can be directly interfaced to and supported by OpenWRT/OLSR software and WIFI radio drivers on certain hardware (H/W that is equipped with mini-PCI slots or over USB-to-mini-PCI adaptors) for which these S/W have been ported.

The Linksys routers currently supported by BBHN can be adapted to use these radios by exposing the USB ports currently present on the Broadcomm chip, adding a power injector and a USB-to-miniPCI adaptor, and loading the USB driver packages for OpenWRT. Certain compatible hardware that may be supported later can use the cards directly.

The 56kbps radio is a radio for a different technical domain, and is generally governed by different sections of Part 97 rules. For example, Radio Amateur use of spread spectrum such as WIFI is currently limited to 10 watts PEP. A packet radio can run the full legal limit. But the bandwidth they can occupy is significantly different.

73;

Bob KV4PC

Bob,

John Hansen tested both the radio's that you posted and presented his findings at a previous DCC.

You are correct that these two radio's can be used with modified linksys gear. But why do that when ALIX type boards from PC concepts are available? Soekris boards will accept those radio cards, as will Mikrotik routerboards.

Enough of this.

The point about the UDR56K that was  presented at DCC is that the 56K barrier may not exist. The presentation at DCC is not included in the proceedings, unfortunately, so unless you were in attendance, you may not find what was discussed on the interweb. You may need to communicate directly with the UDR56k team to learn just what are the capabilities of their radio as the published information is somewhat lacking.

Alternatively, the conference was filmed and I believe the video is available on amateurtelevision website.

73

Marc

KD7RYY

Marc:

Alix, Microtik, etc are examples of the "compatible" hardware I was referring to. I have a couple of Microtik boards myself running Ubiquiti SRs. However, BBHN has not been ported to any of these as yet. And they considerably more expensive. You can make a "compatible" node on them of course but it isnt BBHN.

73;

Bob KV4PC

Bob,

Well, then, you may wish to take a look at the yahoo group for NW-MESH, or at a compendium of some of their work at http://nw-mesh.wikidot.com/

This group in Federal Way Washington has ported an earlier version of HSMM-MESH to Ubiquiti equipment in an attempt to gain the advantage of the higher power available from the bullet M2HP.

There is a proceedure somewhere in their documentation for adjusting Openwrt Attitude Adjustment to mesh with their special build for WRT54XX hardware.

Further HSMM-PI is available for loading onto Raspberry Pi or Beagleboneblack, and will work with every usb wifi dongle that I have tried.

Further, one of the local hams in Vancouver, Wa that is also quite adept at linux has made broadbandhamnet and NW-MESH and older HSMM-MESH talk with eachother.

Of further interest to you might be www.hamwan.org

73

Marc

KD7RYY

Marc:

Interesting links, those. Thank you.

A local ham is working with HSMM-PI on PI and Bone with an eye to getting BBHN compatibility.

I have a couple of Bullet2 I would like to get into BBHN service.There is really alot of compatible or nearly compatible hardware around that is perfectly happy running OpenWRT that I would like to do BBHN.

73;

Bob KV4PC

I'm running a mesh with 1 WRT54GL running BroadbandHamnet-v1 and two HSMM-PIs, works great! Just wish that the BroadbandHamnet interface would display a few of the extra details like note position (once of my nodes is mobile and has a GPS receiver).

I also have a good friend who is using a Bullet in his BBHN mesh; feel free to drop in #broadband-hamnet on Freeenode IRC if you have any questions about all of  these compatabilities -- there are a few of us around every day talking about this stuff!

PS: Next time I go up to Huntsville, maybe we can grab a meal. I'll probably be up there some time in December for an interview. I also pass through a good bit on my way to Nashville.

73 from Tuscaloosa!

K0RET Ryan Turner

Ryan:

Code to display GPS coords on a mesh status page is in this article.

http://hsmm-mesh.org/applications-for-the-mesh/145-gps-on-a-mesh-node.html

KTF

OFDM is permitted on 70 cm because it is an "Image Emission".

[From http://www.ntms.org/802.11/ARRL Board of Directors 2005.doc ]

OFDM Can Be Classified as an Image Emission

John Stevensen, KD6OZH in 2005 began development of a HSMM Orthogonal Frequency Division Multiplexing (OFDM) Modem that will allow Radio Amateurs to have all –mode voice, text, data, and video (i.e., multimedia) high-speed digital communications on the VHF, UHF and SHF bands. Alpha testing of the OFDM modem was done in Texas using an ATV channel in the 70cm band operating in a digital “image mode” coined Amateur Digital Video (ADV).

In a January 2005 report to the ARRL board of directors, the HSMM Technology Task Force submitted the following concept as basis for such a 70 cm OFDM modem capable of Amateur Digital Video.

The 70 cm band is ideal for HSMM and, using the following interpretation of FCC regulations, we should be able to use OFDM modems with an occupied bandwidth up to 9 MHz (at least) on the 70 cm band. HSMM would be classified as an image emission type. This interpretation also allows 6 kHz (or more) bandwidth OFDM modems on the MF and HF amateur bands.

In 47 CFR 97.315 the emission type "image" is defined as including "emissions having B as the first symbol; 7, 8 or 9 as the second symbol; W as the third symbol".

In 47 CFR 2.201 (c) (2) a first symbol of B defines the type of modulation of the main carrier as an "emission in which the main carrier is amplitude-modulated (including cases where sub-carriers are angle-modulated) with independent sidebands". The OFDM modem fits this description as it has a central carrier with multiple subcarriers in the upper and lower sidebands that are angle (phase) modulated. In 47 CFR 2.201 (d) (5) a second symbol of 7 indicates that the nature of the signals modulating the main carrier are "two or more channels containing quantitized or digital information". 47 CFR 2.201 (d)(2) and (3) indicate that time-division multiplex is excluded for a single channel so the time division multiplex inherent in HSMM communications creates two or more channels. In 47 CFR 2.201 (e) (8) a third symbol of W indicates that the type of information to be transmitted is "a combination of the above" and that includes (4) "facsimile", (5) "data transmission, telemetry and telecommand", (6) "telephony" and (7) "television". HSMM fits this definition as it includes data, speech and image components.

In 47 CFR 97.305 "a station may transmit the following emission types on the frequencies indicated, as authorized to the control operator, subject to the standards specified in 97.307(f) of this part". The following table includes the "image" type for all bands and references 47 CFR 97.307 (f) (2) for the 160 m through 1.25 m bands but does not reference it for the 70 cm through 1 mm bands.

This is the only restriction on the image emission type and states that "the total bandwidth of an independent sideband emission (having B as the first symbol), or a multiplexed image and phone emission, shall not exceed that of a communications quality A3E emission". I can't find a definition for "communications quality" but it seems to be taken as 3 kHz on the MF and HF bands.

Thus OFDM modems using 6 kHz or less should be authorized on 225 MHz and below and OFDM modems with no bandwidth restriction on 420 MHz and above. If the emission must fit within the bandwidth used by existing analog image communication devices, that bandwidth would be 9 MHz for DSM AM ATV with a 4.5 MHz sound subcarrier.