Hello Guillaume,
Great to hear that you're willing to try narrower bandwidth offerings! That's a huge help to give this new mode you're working on a try. To your other point, unfortunately yes, the FCC restrictions here in the US are antiquated. Until they can be changed (the request is already been pending for YEARS), we have to live with them. Please not that it's the *symbol* rate that's limited for say 70cm. I would imagine that 70cm would be the most popular band to use in the US to experiment compared to say 33 cm or 23cm.
I had to look up the whole thing again but here is the exact FCC wording:
http://www.arrl.org/part-97-text *§97.305 Authorized emission types.*
--
UHF:
70 cm
Entire band
MCW, phone, image, RTTY, data, SS, test
(6), (8).
33 cm
Entire band
MCW, phone, image, RTTY, data, SS, test, pulse
(7), (8), and (12).
23 cm
Entire band
MCW, phone, image, RTTY, data, SS, test
(7), (8), and (12).
(f) The following standards and limitations apply to transmissions on the frequencies specified in §97.305(c) of this part.
(6) A RTTY, data or multiplexed emission using a specified digital code listed in §97.309(a) of this part may be transmitted. The symbol rate must not exceed 56 kilobauds. A RTTY, data or multiplexed emission using an unspecified digital code under the limitations listed in §97.309(b) of this part also may be transmitted. The authorized bandwidth is 100 kHz.
(7) A RTTY, data or multiplexed emission using a specified digital code listed in §97.309(a) of this part or an unspecified digital code under the limitations listed in §97.309(b) of this part may be transmitted.--
(8) A RTTY or data emission having designators with A, B, C, D, E, F, G, H, J or R as the first symbol; 1, 2, 7, 9 or X as the second symbol; and D or W as the third symbol is also authorized.
(12) Emission F8E may be transmitted. --
--David KI6ZHD
On 06/03/2019 01:16 PM, f4hdk wrote:
Hello,
Yes, I will try to provide smaller bandwidths in the following months (or weeks?) for NPR. Probably ~180kHz, which could carry ~90kbps with 2GFSK and ~160kbps with 4GFSK (net datarate).
But I don't think that I will propose modulation parameters which could match the (very small) FCC restrictions (100kHz and 56kbaud if I remember well). This rule seems outdated to me... even if it still applies.
Do not hesitate to take a look regularly at my hackaday web-page in order to keep informed about "New Packet Radio". https://hackaday.io/project/164092-npr-new-packet-radio
73, Guillaume F4HDK
Le 03/06/2019 à 04:00, David Ranch a écrit :
Great to hear and thanks for the update Mark. Has there been any mention of supporting smaller bandwidths in the future?
--David KI6ZHD
On 06/02/2019 05:27 PM, Mark Phillips wrote:
Got a pair of these modems working! They are just running across the bench right now. I have an RPi3 and a MMDVM hotspot connected to the client (via a switch) with the master connected to a spare port on the back of my pfSense firewall. I'm using mode "22" which is 270KHz wide for about 220kbps of data bandwidth. This seems more than able to handle the serving of a web age and running the MMDVM. I also did a test in 500kbps mode using a wifi hotspot attached to the client. I was able to sustain a "wifi calling" cellphone conversation for over an hour with no issues.
For those not following the project, new firmware was released this weekend that allows tuning of the RF from 420-450MHz which is a great improvement over the EU only bandplan.
Take a look here http://g7ltt.dyndns.org:2210
Mark G7LTT/NI2O
On Tue, Mar 26, 2019 at 4:24 PM Steve L via 44Net 44net@mailman.ampr.org wrote:
In case anyone feels the need:
It's pretty easy to file a petition through the ECFS. When you go to the main ECFS page https://www.fcc.gov/ecfs/filings in "Type of filing" select "petition for rule making", and fill out the rest of the form and upload your petition.
A couple useful pages from the FCC: < https://www.publicknowledge.org/assets/uploads/blog/RP_FCCPetitiontoDeny.pdf
https://www.fcc.gov/about-fcc/rulemaking-process Here is a quick summary from the last one, three are more details on the page. *Organized comments*. *Clear explanation and support for views*. *Alternatives. * *Examples of concerns.* *Statutory limitations.*
It's also helpful to review recent amateur petitions and the FCC response. The rejections are a wealth of information on what not to do. It might be advisable to suggest RM-11392 and DA 08-1092 rejection, RM-11699 and DA 13-1918 rejection, as starting points since its somewhat related.
Don't use ham jargon, be sure sure to explain acronyms at least once in the filing, if repeated makes it easier to follow. Don't bash other amateur modes or practices. Don't use technical terms unless fully explained so a lawyer can understand, most on the Commission are non-tech types. Don't ask to ban anything, if you want that done make the case to the FCC that whatever it is is poor practice without requesting a ban......let them do it.
Do make your petition concise and to the point without a lot of rambling and legalese. Do provide a reason as to why it's a benefit to the amateur service as a whole, also in the public interest if it applies. Do have someone, with the background to understand it, proofread and comment. Do be ready for rebuttal of comments if there are any opposing....wait for the "reply to comment" period, this isn't an internet forum squabble. Keep comments/reply to civil and professional.
On Sun, Mar 24, 2019 at 3:13 PM Ron Economos via 44Net 44net@mailman.ampr.org wrote:
This keeps coming up. Has anyone ever submitted a petition for rule making to the FCC? Or are folks afraid that stirring the pot will get DATV banned on 70 cm?
Ron W6RZ
44Net mailing list 44Net@mailman.ampr.org https://mailman.ampr.org/mailman/listinfo/44net