Search found 46 matches

by Wowbagger
Wed Sep 04, 2013 6:36 am
Forum: Astro DStar and other digital voice formats
Topic: I scored a few of these but have no idea...
Replies: 8
Views: 6906

Re: I scored a few of these but have no idea...

[quote="motorola_otaku"Yaesu had one of their "C$FM FDMA" radios on display at HamCom. There was no accompanying documentation, ad slicks, or anything in the way of support. Wish I'd had a waveform analyzer handy because it definitely is not speaking P25 or TRBO.[/quote] Probably...
by Wowbagger
Sun Aug 12, 2012 1:19 am
Forum: HAMFESTS!!!
Topic: Joplin - August 24-25, 2012
Replies: 7
Views: 4139

Re: Joplin - August 24-25, 2012

I may have to give it a miss. The Cosmosphere is having it's 50th that weekend - a one-in-a-lifetime event vs. a yearly event. Hmmm. Let me think.
by Wowbagger
Sat Aug 11, 2012 11:45 am
Forum: HAMFESTS!!!
Topic: Joplin - August 24-25, 2012
Replies: 7
Views: 4139

Re: Joplin - August 24-25, 2012

Well, were I coming down from Des Moines, I'd at least plan on a little time in KC, and plan on doing some of the more interesting attractions around Joplin, and make a weekend of it - head over to Springfield to Bass Pro, eat at Lamberts, maybe take a couple of drives around the Branson area. If I ...
by Wowbagger
Fri Aug 10, 2012 2:47 pm
Forum: HAMFESTS!!!
Topic: Joplin - August 24-25, 2012
Replies: 7
Views: 4139

Re: Joplin - August 24-25, 2012

I'm tempted to go, as an excuse to get over to that area (since I stopped doing Route 66 on the Air I've lost that excuse).

But I'd round it out by doing some other Route 66 attractions (4 women on the route, the inn in Baxter Springs, then a run through Tulsa and OKC before heading home).
by Wowbagger
Tue Feb 28, 2012 10:49 am
Forum: Astro DStar and other digital voice formats
Topic: P25 Phase 2
Replies: 9
Views: 5783

Re: P25 Phase 2

I.. what. How does that even work without incurring delays in channel grants? Also I'm looking at your own company's application note on P25 control channels and don't see this mentioned. Time for an update maybe? The worst case delay on a channel grant using only one slot of a channel as the contr...
by Wowbagger
Mon Feb 27, 2012 3:49 pm
Forum: Astro DStar and other digital voice formats
Topic: P25 Phase 2
Replies: 9
Views: 5783

Re: P25 Phase 2

Right now the only Phase 2 solution on the table is Motorola's X2 TDMA system. It's essentially the same thing as Astro25 but with 2:1 TDMA capability. The control channel is Phase 1 and the vocoder is still IMBE. Wrong. The control channel *can be* Phase 1 style, OR can be a TDMA channel, either o...
by Wowbagger
Sun Oct 24, 2010 9:17 pm
Forum: EQUIPMENT REVIEWS
Topic: Flex 1500
Replies: 6
Views: 10312

Re: Flex 1500

I've been waiting for Flex to get the software running under Linux. I'd talked to the president when he was in town for the Central States Microwave society meeting (I'd persuaded work that it would be worth having a table there - and since we both do SDR, we talked shop), and they were supposedly w...
by Wowbagger
Fri Apr 30, 2010 8:01 am
Forum: VoIP/IRLP/EchoLink etc
Topic: Low latency IP Audio streaming for remote base?
Replies: 14
Views: 9774

Re: Low latency IP Audio streaming for remote base?

I'm not sure Skype gives me anything Ekiga doesn't - both need a central server to set up the call, and at least with Ekiga I can think about running my own SIP server that I control access to.
by Wowbagger
Thu Apr 29, 2010 5:46 pm
Forum: VoIP/IRLP/EchoLink etc
Topic: Low latency IP Audio streaming for remote base?
Replies: 14
Views: 9774

Re: Low latency IP Audio streaming for remote base?

Not that I am aware of: likely, the radios will be my IC7000, and a SDR5000 borrowed from work - Which one I use for receive and which one I use for transmit is still open for debate, but I am leaning toward the SDR doing RX at home and my 7000 doing TX.
by Wowbagger
Thu Apr 29, 2010 9:46 am
Forum: VoIP/IRLP/EchoLink etc
Topic: Low latency IP Audio streaming for remote base?
Replies: 14
Views: 9774

Re: Low latency IP Audio streaming for remote base?

Well, I've been doing a bit of experimentation, so I'll share: Experiment #1: icecast2 + ices2 (http audio streaming) Verdict: Unsatisfactory - buffering adds a minimum of 2 seconds latency. If the system is configured to use a low bitrate then it is even worse, as many clients insist upon buffering...
by Wowbagger
Wed Apr 28, 2010 11:12 am
Forum: VoIP/IRLP/EchoLink etc
Topic: Low latency IP Audio streaming for remote base?
Replies: 14
Views: 9774

Re: Low latency IP Audio streaming for remote base?

I saw an ad for these guys in CQ yesterday but don't know a thing about them: http://www.glentekcorp.com/ Their solution to IP latency is to use a POTS line for audio back to the operator with the IP side handling radio control. I don't guess the remote base site will be close enough to use point-p...
by Wowbagger
Wed Apr 28, 2010 8:12 am
Forum: VoIP/IRLP/EchoLink etc
Topic: Low latency IP Audio streaming for remote base?
Replies: 14
Views: 9774

Low latency IP Audio streaming for remote base?

I'm helping my club out on setting up Kids Day on the Air this June 19th. Unfortunately, the site we pretty much have to work from has a S7 noise floor, with interfering signals as high as -60dBm! - not exactly conducive to HF contacts. The plan is to operate a remote base for receive, somewhere wit...
by Wowbagger
Thu Oct 15, 2009 7:21 am
Forum: Astro DStar and other digital voice formats
Topic: amplification and p25
Replies: 6
Views: 5238

Re: amplification and p25

C4FM is FM - a class C amp won't do anything to it, because the signal is constant amplitude. Now, if you were to be using the CQPSK modulation scheme and you used a class C amp, you'd basically end up turning the signal into C4FM - you'd widen the spectrum back out to 12.5kHz rather than 6.25kHz. T...
by Wowbagger
Fri Aug 21, 2009 7:23 am
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

OK cool, that puts my mind at rest. I expected as much re the wide pulse/LSM/other proprietary stuff Yes - ADP algorithm isn't part of the P25 spec, so I would automatically consider that to be proprietary. Here's where it gets tricky though. the Keyfill interface/protocol *is* part of the publicly...
by Wowbagger
Thu Aug 20, 2009 8:55 pm
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

Point number 2 is the one that intrigues me - OP25 has been implemented from the TIA/ETSI specs and publicly available information such as the Daniels P25 training manual - nothing more.. Apart from the DVSI stuff, is there anything else that's encumbered by NDA/patents? Oh, things like how Motorol...
by Wowbagger
Thu Aug 20, 2009 1:55 pm
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

Like any software project, (especially one like OP25) this project has people with all sorts of eclectic skills. Join the mailing list and you'll see exactly how/what I contribute. Surely your employer won't discipline you for reading up on our efforts. It's not a question of that - it's the questi...
by Wowbagger
Thu Aug 20, 2009 9:39 am
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

Very impressive. Are you a contributor to the code, or "just a user" (not that being "just a user" is a bad thing, as good user feedback is VERY important)? I am interested in this project, but due to my position I get nervous when thinking about looking at or contributing, due t...
by Wowbagger
Sat Jul 11, 2009 7:14 am
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

OP25 will get there. Once the receive code is complete, then work will start on tx code. Cheers, Matt How are you handling the vocoding? Are you using the DVSI USB dongle, or just spacing that bit off for now? Also, are you deriving any of the parametrics on the signal, such as Mod Fidelity error o...
by Wowbagger
Thu Apr 09, 2009 7:05 am
Forum: Astro DStar and other digital voice formats
Topic: Please Edumacate me...
Replies: 60
Views: 36564

Re: D-Star is a disappoitment

Sorry, but I need to vent: D-Star is only a 4800 bis per second total data stream equivalent signal. 2400 bis per second are reserved for actual digital voice, 1200 bis per second are reserved for FEC (forward error correction) on the igital voice. (This is for callsign and short message data.) Ano...
by Wowbagger
Tue Nov 04, 2008 12:10 pm
Forum: Astro DStar and other digital voice formats
Topic: NXDN?
Replies: 14
Views: 9767

Re: NXDN?

And yet more "DVSI has everyone by the balls" proprietary vocoder shit. :ve4uo: Well, they are like the only group actually making vocoders. Wrong. There are plenty of other vocoders out there. The problem is one of inertia: since developers of communications protocols are already using D...
by Wowbagger
Sun Nov 02, 2008 8:39 am
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

Even the engineers working down the hall from me have a fuckload of trouble getting CML samples. Buy a USRP with the appropriate transmitter and reciever modules, and... http://www.sedition.org.au/op25/ :baby: Iiiiiiiiinterestink. However, I think they are going to have real problems with the IMBE ...
by Wowbagger
Wed Jul 16, 2008 5:13 pm
Forum: HAMFESTS!!!
Topic: Central States VHF Society Annual Conference
Replies: 0
Views: 12346

Central States VHF Society Annual Conference

The Central States VHF Society Annual Conference is next week (24th July 2008 - 26th July 2008) at the Airport Hilton in Wichita. Any other hamsexuals going to be there? I brought it to our (Aeroflex Wichita) Marketing/Communications guys, and we are going to have a table there, and I got drafted as...
by Wowbagger
Sat Jul 05, 2008 11:19 am
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

Get er done! :baby: That's kind of what I was trying to do with the hardware here. Where would a person get the specs for the protocol, enough to do something like that? Either from the TIA, or I think there's enough information on the Internet that, if you have enough background in signal processi...
by Wowbagger
Fri Jul 04, 2008 8:55 am
Forum: Astro DStar and other digital voice formats
Topic: P25 repeaters
Replies: 75
Views: 55816

Re: P25 repeaters

I'm rather surprised somebody hasn't done the simpler idea of just using a low-cost low-power DSP to: 1) take the flat RX audio (discriminator audio) and recover the CAI symbol stream. 2) take that symbol stream and regenerate the idealized waveform out to the flat TX input. The DSP wouldn't have to...
by Wowbagger
Sun Jun 15, 2008 8:48 am
Forum: HAMFESTS!!!
Topic: HamCom 2008 - Plano, TX
Replies: 44
Views: 20946

Re: HamCom 2008 - Plano, TX

I might have liked to go, but unfortunately I was ministering to an ailing repeater. That was a weird one: the machine had gone deaf. I got to the site, plugged the RX into my service monitor, and did a quick check: -120dBm for 12dB SINAD. OK, so maybe the antenna is bad. It's a bit of a trick to ch...
by Wowbagger
Tue Jun 03, 2008 11:15 am
Forum: HAMFESTS!!!
Topic: HamCom 2008 - Plano, TX
Replies: 44
Views: 20946

Re: HamCom 2008 - Plano, TX

I'd have said "Get your towel (you DO know where your towel is, don't you?), place it between the antenna and the car, and strap it on the side of the car, running from hood to trunk, tied through the passenger side windows and at the hood and trunk. Bonus points for using it as a lance <sfx fr...
by Wowbagger
Thu Dec 13, 2007 11:00 am
Forum: Astro DStar and other digital voice formats
Topic: Astro modulation type
Replies: 3
Views: 3895

Re: Astro modulation type

C4FM CQPSK WIDE What's the difference? Which should I use? Short answer: whatever the system you are on uses. Longer answer: C4FM is the APCO-25 standard specified modulation. It occupies a 12.5 kHz channel, and has no AM component (it is pure FM), and so does not require a linear amplifier. CQPSK ...
by Wowbagger
Mon Sep 24, 2007 1:59 pm
Forum: VoIP/IRLP/EchoLink etc
Topic: IRLP - The Fedora Legacy Project is shutting down, by WY0X
Replies: 8
Views: 5984

Re: IRLP - The Fedora Legacy Project is shutting down, by WY

FYI folks, The Fedora Legacy Project is shutting down. This will mean that all Fedora nodes won't have security updates via yum, probably effective relatively immediately. I think you may be confusing two different things. The Fedora Legacy project was the project for Fedora before Redhat became in...
by Wowbagger
Tue Sep 18, 2007 4:10 pm
Forum: HAMFESTS!!!
Topic: Route 66 on the Air, Sept 8th 2007 to 16th Sept 2007
Replies: 3
Views: 2055

1057 contacts

Well, we made about 1057 contacts, on 20, 40, and 80 - furthest contact was Moscow Russia. Not bad, considering that all but Wednesday we were a single radio station - Wednesday some guys from Chanute Kansas showed up with their radio, so I let them have the G5RV and I worked with my Mini Tarheel on...
by Wowbagger
Fri Sep 07, 2007 5:32 pm
Forum: HAMFESTS!!!
Topic: Route 66 on the Air, Sept 8th 2007 to 16th Sept 2007
Replies: 3
Views: 2055

Bump

by Wowbagger
Fri Sep 07, 2007 7:25 am
Forum: Astro DStar and other digital voice formats
Topic: Hetrodynes... does it happen with...
Replies: 17
Views: 10247

Back on topic. Does transmit deviation matter for P25? I just thought, if I'm using 2.5kHz deviation and my mate is using 5kHz, does it matter? (apart from bandwidth use??) P25 is not like analog FM - there is a specified deviation for the symbols, and if you aren't at that deviation you aren't mak...
by Wowbagger
Tue Sep 04, 2007 5:50 pm
Forum: Astro DStar and other digital voice formats
Topic: Hetrodynes... does it happen with...
Replies: 17
Views: 10247

by Wowbagger
Tue Sep 04, 2007 2:56 pm
Forum: Astro DStar and other digital voice formats
Topic: Hetrodynes... does it happen with...
Replies: 17
Views: 10247

Re: Hetrodynes... does it happen with...

First of all: VOCODERS ARE NOT PROTOCOLS! You are using some protocol which uses IMBE as a protocol (e.g. you are using APCO-25 CAI). Saying you are using "IMBE" is like saying you are using "big". If anything - analog or digital - interferes with a digital protocol, then the res...

Go to advanced search