This (troubleshooting why you're not getting heard) would be a good topic for a Wiki article. I'll start it myself when I have a chance, but if someone else wanted to take a shot at it that'd be great.
Scott James Ewen wrote: > > > On Fri, Oct 30, 2009 at 11:03 AM, Kevin Jensen <[email protected] > <mailto:ktjensen%40gmail.com>> wrote: > > > 1) 15 seconds only matters, if someone can hear my packets. > > Sure, if you are in the middle of no where, hundreds of miles from > anyone on 144.390, this is true. You're not quite in that situation in > West Haven. There are a LOT of stations within 20 miles of you. You > are very probably being heard over that kind of range. Digipeaters > with good HAAT will easily hear you over that distance. > > > That is still an issue, as they are not getting through for some reason. > > Getting through is a totally different issue than being heard. While > it is true that you "won't get through" without being heard, the > opposite is not true. You could very well be heard by MANY stations, > but because of issues such as deviation misadjustment, you won't "get > through". Being heard and being decoded are related but not equal. > > > Maybe 5 to 10 get through and are displayed on APRS.FI for the 20 > > minute trip to work in the morning. Nothing else gets through. > > So, some stations are able to hear AND decode your packets. This tells > us that for the most part everything is working on your setup... this > could still indicate an improper deviation, low power output/bad SWR, > or something like that causing problems. > > > The > > packet frequency is not that busy. I can hear packets from several > > other stations, and they all display on my Nuvi 350. > > The packet frequency is not that busy from your perspective. You can > only hear the activity that is within simplex range of your station. > Let's say that for arguement's sake that is a 20 mile radius around > your vehicle. Digipeaters are usually located where they have a pretty > good view of the area around them. Let's say a digipeater 10 miles > away can hear an area with a 30 mile radius. That digipeater can hear > everything you can, and a whole lot more. If there are stations within > range of the digipeater that are sending packets at the same time you > are, at best, one of the two stations are going to be heard by FM > capture effect. Worst case, both packets are garbage. Now consider > that neighboring digipeaters will usually be able to be heard by the > local digipeater, even if they are further than 30 miles away simply > due to the fact that the digis are up on high spots. > > Digipeaters are hubs of activity, repeating packets like crazy. They > listen to all activity on the frequency, and only digipeat those > packets asking for another hop. Packets that have paths that are used > up are still heard, but not digipeated. This still takes up time on > the digipeater even if it's not going to digipeat the signal. For you > as a user in the digipeater area, it might sound like there's not a > lot of activity, but for the digipeater, it might be another story. > Try driving up on a hilltop nearby one day and have a listen to > 144.390 for a while. See if it still sounds really quiet. > > > 2) Have tried setting SMART to ON with appropriate parameters (as > > suggested here), and an INTERVAL of 2 minutes. With these settings, I > > get two or three packets through on my 20 minute trip. > > Yes, because SmartBeaconing is going to send fewer packets than your > 15 second interval. Throwing hundreds of baseballs at a dunk tank > target gives you lots of opportunity to hit the target, but a couple > well aimed baseballs that hit the target means your arm is not as sore > at the end of the day. > > > 3) Do I have something wrong? > > Most likely... first culprit to look at is deviation, as it is a very > common setting to have set wrong. > > > Does a packet contain all the last > > several coordinate breadcrumb trails in it (several gps coordinate > > sets that are stored over the last several minutes)? Or does a packet > > only contain the last single coordinate set, for the moment? I think > > the latter. > > You are correct. The packet only contains the current GPS information. > Regular APRS does not do any buffering of information. APRS is a fire > and forget protocol. There's no way for your station to know if the > packets you are sending are being heard by anyone. > > > 4) I can hear the packets fine with my stand alone HT radio, with > > APRS. They should like everyone elses packets. But maybe I do need > > to adjust the volume settings (what is that command?) so that the > > modulation is improved. Maybe I am undermodulating the packet, with > > my audio from the TRACKER? > > Using OTWINCFG, and playing with the modulation control will let you > test... I'd listen on another radio, and if possible watch another > APRS radio to see if the packets are being decoded, or as a last > resort watch the computer to see if you are making it to the APRS-IS. > > > 5) Also need to check my radio and its baud rate. Do not recall if > > it is set to 1200 or not. It should be at that setting I assume? > > No need to worry about a baud rate in the radio. You said you were > using a TM-V71 and an OT2... you should be feeding audio tones into > that radio, not digital data. > > > Thanks for all the comments. They all make sense during investigation > > of optimal APRS. > > Let's keep going to see if we can get you better reliability so you'll > reduce your packet rate from 15 seconds down to something reasonable. > > Right now it's like you're standing in the middle of a room shouting, > but none of those around you can understand what you are saying. We > need to help you reduce the volume, and increase intelligibility. The > end result is better communication all around. > > James > VE6SRV > >
