---------------------------------------------------------------------- Subject: Re: APRN the best setup From: WA8LMF2@aol.com Date: Sat, 7 Dec 2002 02:14:04 EST X-Message-Number: 1 In a message dated 12/6/2002 9:02:23 PM Pacific Standard Time, wolthui3@msu.edu writes: > What I am not sure of is can you send the SSTV image say every 5minutes > on 144.390 without disrupting the APRS traffic greatly? NO!!!! Furthermore, the VC-H1 is almost impossbile to mode switch into the auto-beacon mode without an external software application controlling it. [ I have often wished for a convenient way to do this without a computer controlling it for use with my "Mobile LiveCAM" while driving cross country. ] > If not can you > use band B on the d700a on a secondary frequency for SSTV while still > having APRS on band A? The APRN concept is similar to Mic-E APRS-burst-after-voice transmission -- The APRS data burst is completely separate from the SSTV transmission that precedes it. Both are transmitted on the same frequency, and are normally conducted on a non-APRS frequency. At the fixed station: Basically, you feed the base station receiver audio into BOTH a TNC connected to a standard APRS mappping application AND into the computer sound card connected to an SSTV reception application. [ Any of the standard soundcard SSTV apps that can automatically save a received image into a JPG file can be used. The freeware mmSSTV works very well for this application. ] [ Of course the big-bucks luxo approach to this would be to use a D700 at the fixed station as well. The internal TNC could decode the APRS burst and the sound card interface can be connected to the 6-pin mini-DIN "External TNC" connector on the D700. [ This connector is actually just RX audio, TX audio and PTT suitable for external TNCs, soundcard interfaces, repeater controllers, etc. In the mobile you are probably using this port to connect the VC-H1 which again, like any SSTV device need RX audio, TX audio and PTT keying. ] The complexity comes after that. A third program then has to: 1) Monitor for the appearance of a new JPG image file. 2) Screen cap the APRS map image into a file when a new SSTV image is detected 3) Assemble the two images above into an HTML page. 4) FTP the HTML page and two images to a web site. Other random considerations: The VC-H1 powers up defaulted to the Robot 36 transmission mode. Unless it hears some other mode on receive, it is stuck in this mode, unless an external computer controller commands it into another mode. While R36 is great for CQing (it's the shortest transmission time of any SSTV mode outside of the classic 8-second B&W mode SSTV started with 30 years ago), the resolution and image quality leaves a lot to be desired. If you want to transmit scenics and other complex images, the unit will need to be commanded into a higher quality mode such as the very popular Scottie 2 mode (90 seconds transmission time). The VC-H1's internal firmware is HORRENDOUSLY BUGGY. Once the device switches into Scottie2, it will not transmit more than 4 or 5 times without locking up and crashing. You then have to cycle the power off and back on which makes it reset to Robot 36! The provided camera head on the VC-H1 is really awful. It's a low-res fixed-focus CCD imager similar to the ones in X10 spycams or home security CCTV systems. The field of view is excessively wide angle (equivalent of about a 30mm lens on a 35 SLR) which further aggravates the resolution problem since most subjects show up far too small in the image. You can remove the camera head and expose a 3.5mm stereo mini-jack. Plug in an external NTSC image source The image quality will be about 1000% better. [ I have used some ot the original Kodak 640x480 digicams with 3:1 optical zoom lenses that ranged from 35-100MM equivalent very successfully for this purpose. These are often available second-hand very cheaply since the outbreak of "megapixel mania" in the digicam market. Since all the standard SSTV modes that the VC-H1 transmits are 320x240 pixels, such a camera has more than enough resolution. ] More details on my mobile SSTV "LiveCAM" setup at my webpage at: http://wa8lmf.com Stephen H. Smith [ who has been on SSTV for over 30 years ] Home Page: http://wa8lmf.com Ham Radio/Mobile SSTV page: http://members.aol.com/wa8lmf/ham APRS Stuff http://members.aol.com/wa8lmf/aprs | Radio Communications Systems Personal Computers | Consulting and Systems Integration | GPS Custom Mapping & Radio Coverage Surveys | File Conversions MS-Windows Setups Networking ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: "Pat Karp" Date: Sat, 7 Dec 2002 08:27:01 -0600 X-Message-Number: 6 > The complexity comes after that. A third program then has to: > 1) Monitor for the appearance of a new JPG image file. > 2) Screen cap the APRS map image into a file when a new SSTV image is > detected > 3) Assemble the two images above into an HTML page. > 4) FTP the HTML page and two images to a web site. The Program APRN does just that. However it creates a new page each time Without deleting the old one. I wrote a little utility that would watch a directory for a new file to appear. This file can be anything you select but does require you to specify the name of it in advance. Then it will upload it to your Website. It should support all of the Inet transfer protocols although all be the FTP is untested. After it uploads the file it erases the local file and waits for it to reappear. I have often thought about doing the same thing with SSTV only using 440 and making a separate station to handle the traffic for it. But I could never find all the peace's to make it work. But will keep working on it. In light of this tread I will look into the way SSTV software saves the pictures and maybe adjust my little program to work with it. ;-) ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: Roger Grady Date: Sat, 07 Dec 2002 12:53:40 -0500 X-Message-Number: 10 At 02:14 AM 12/7/02 EST, WA8LMF2@aol.com wrote: >Furthermore, the VC-H1 is almost impossbile to mode switch into the >auto-beacon mode without an external software application controlling it. [ >I have often wished for a convenient way to do this without a computer >controlling it for use with my "Mobile LiveCAM" while driving cross country. This brings up a question - I don't have the VC-H1 software that Kenwood sells but I've read that it's a great example of how not to design user interfaces, to put it charitably. Has anyone ever seen any other software to interface with the VC-H1? Roger Grady K9OPO ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: David VanHorn Date: Sat, 07 Dec 2002 14:52:57 -0500 X-Message-Number: 17 At 12:53 PM 12/7/2002 -0500, Roger Grady wrote: >At 02:14 AM 12/7/02 EST, WA8LMF2@aol.com wrote: >>Furthermore, the VC-H1 is almost impossbile to mode switch into the >>auto-beacon mode without an external software application controlling it. [ >>I have often wished for a convenient way to do this without a computer >>controlling it for use with my "Mobile LiveCAM" while driving cross country. > >This brings up a question - I don't have the VC-H1 software that Kenwood >sells but I've read that it's a great example of how not to design user >interfaces, to put it charitably. Has anyone ever seen any other software >to interface with the VC-H1? I don't think there is any. I would agree, it's thoroughly excerable. I think, for APRN to work, the station ID and position need to be in the SSTV data. Otherwise, you're making a large assumption that the position packet and picture are related. Chromapix talks about a "caller ID" feature, apparently some sort of low data rate encoding before the picture is sent. I haven't been able to find any information on it though. I've been using two of the VC-H1s, and a Tasco converter here, with chromapix, for skywarn. It's SO nice to get radar updates in the field. ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: Bob Bruninga Date: Sat, 7 Dec 2002 15:39:11 -0500 (EST) X-Message-Number: 21 > In a message dated 12/6/2002 9:02:23 PM Pacific Standard Time, > wolthui3@msu.edu writes: > > > What I am not sure of is can you send the SSTV image say every 5minutes > > on 144.390 without disrupting the APRS traffic greatly? APRS is a concept for uplinking live SSTV images from mobiles, to a SSTV receiver for direct aving to a WEB page for instant access by anyone with a browser. It was never intended to do the SSTV uplinnk on APRS. The uplink takes place on a local simplex or repeater. APRS is only used to send a single STATUS packet to identify the SOURCE, and LOCATION of the image for futuer automatic reference by the web page. See the APRN idea web page. http://www.ew.usna.edu/~bruninga/aprn.html But glad to see someone is thinking on persuing these concepts. They are very powerful... de WB4APR ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: "Dick C. Reichenbach" Date: Sat, 07 Dec 2002 16:35:18 -0500 X-Message-Number: 23 I'm currently working on some APRN stuff. Humble though they may be, here are my thoughts. I installed soundmodem. It is capable of decoding the packets. I have also compiled but not yet tested or configured the AX.25 application WAMPES. I put an extra sound card in my UNIX box. I also installed OSS drivers. They have the option of splitting the /dev/dsp output into multiple output streams. So I can connect the QSSTV application to one virtual device and the Soundmodem to the other virtual device. I also got QSSTV to compile. It receives pictures ok, but doesn't send them. Although sending pictures isn't nessasary for this application, I would still like to have that capability. This is as far as I have physically gotten. Future steps are: A script, probably perl, will listen for messages sent to my station. When it hears a message like "SSTV 146.55 Scottie2", it will change the frequency of my radio to 146.55, and set a unix "lock", and set QSSTV to Scottie2 and respond with "SSTV receive ready". I should be able to do this with AX.25 ports and it wouldn't interfere with Xastir. In theory. The mobile station could then send the picture (on 146.55) with the appropriate tag on the end. My station would probably respond with the ack message. (on the APRS freq) The spool lock on the radio could then be released and the radio retuned to the PCSAT d/l frequncy, or any other frequency for that matter. The perl script would take off the tag and store it in (probably) a mySQL database along with the filename and location of the picture file. The database could be searched and any picture displayed along with the location of the sending station. This could be done ala "Findu style". Where the maps aren't stored picture files, but generated on the fly from information stored in a database. And the sent SSTV picture is displayed underneath the map. Take care, 73 Dick Reichenbach - KC8OBZ Bob Bruninga wrote: > > In a message dated 12/6/2002 9:02:23 PM Pacific Standard Time, > > wolthui3@msu.edu writes: > > > > > What I am not sure of is can you send the SSTV image say every 5minutes > > > on 144.390 without disrupting the APRS traffic greatly? > > APRS is a concept for uplinking live SSTV images from mobiles, to a SSTV > receiver for direct aving to a WEB page for instant access by anyone with > a browser. It was never intended to do the SSTV uplinnk on APRS. The > uplink takes place on a local simplex or repeater. APRS is only used to > send a single STATUS packet to identify the SOURCE, and LOCATION of the > image for futuer automatic reference by the web page. > > See the APRN idea web page. > > http://www.ew.usna.edu/~bruninga/aprn.html > > But glad to see someone is thinking on persuing these concepts. They are > very powerful... > > de WB4APR > > --- > You are currently subscribed to aprssig as: dreichen@columbus.rr.com > To unsubscribe send a blank email to leave-aprssig-28336O@lists.tapr.org > Questions regarding the SIG go to the SIG administrator: wa1lou@tapr.org ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: Bob Bruninga Date: Sat, 7 Dec 2002 21:17:51 -0500 (EST) X-Message-Number: 29 On Sat, 7 Dec 2002, Dick C. Reichenbach wrote: > I'm currently working on some APRN stuff. Humble though they may be, > here are my thoughts. Here is an IDEA I just had today. Sinec the tones for SSTV go between 1200 and 2300HZ and AX.25 packet is 1200 and 2200 Hz, then it is possible that a short AX.25 packet can be sent within a line of SSTV! If the shortest packet is something like WB4APR>MYBOAT: Then we can send the SENDERS call and a 6 character IMAGE name in only about 18 characters of AX.25 (or so). The original SSTV was 15 lines per second or about 70 ms per line. SHucks, it takes about 125 ms to send that shortest packet. Nevermind. But close... But imagine if we could, then a TNC monitoring SSTV would show who is sending what... de WB4APR, Bob ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: "Wes Johnston" Date: Sun, 8 Dec 2002 00:17:31 -0500 X-Message-Number: 1 Sounds something like closed captioning on SSTV... very interestign indeed. One line of video (or retrace) becomes data.... Wes ----- Original Message ----- From: "Bob Bruninga" To: "TAPR APRS Special Interest Group" Cc: "TAPR APRS Special Interest Group" Sent: Saturday, December 07, 2002 9:17 PM Subject: [aprssig] Re: APRN the best setup > On Sat, 7 Dec 2002, Dick C. Reichenbach wrote: > > > I'm currently working on some APRN stuff. Humble though they may be, > > here are my thoughts. > > Here is an IDEA I just had today. Sinec the tones for SSTV go between > 1200 and 2300HZ and AX.25 packet is 1200 and 2200 Hz, then it is possible > that a short AX.25 packet can be sent within a line of SSTV! > > If the shortest packet is something like WB4APR>MYBOAT: > > Then we can send the SENDERS call and a 6 character IMAGE name in only > about 18 characters of AX.25 (or so). The original SSTV was 15 lines per > second or about 70 ms per line. SHucks, it takes about 125 ms to send > that shortest packet. Nevermind. But close... > > But imagine if we could, then a TNC monitoring SSTV would show who is > sending what... > > de WB4APR, Bob > > > > --- > You are currently subscribed to aprssig as: kd4rdb@netzero.com > To unsubscribe send a blank email to leave-aprssig-28336O@lists.tapr.org > Questions regarding the SIG go to the SIG administrator: wa1lou@tapr.org > > ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Re: APRN the best setup From: David VanHorn Date: Sun, 08 Dec 2002 00:33:53 -0500 X-Message-Number: 2 At 12:17 AM 12/8/2002 -0500, Wes Johnston wrote: >Sounds something like closed captioning on SSTV... very interestign indeed. >One line of video (or retrace) becomes data.... Apparently this already exists, see the chromapix dox, where they talk about "caller ID", apparently a way of tagging the image to a callsign. If you have a callsign and a time, you can get the position from the APRS stream, we don't need to put it in the picture data. ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: SSTV & packet From: Tom Weeden Date: Sun, 08 Dec 2002 19:26:39 -0600 X-Message-Number: 12 The very nice freeware program MMSSTV has many options that I've never heard of before. One is FSKID. If you enable FSKID, the program will encode your callsign in FSK at the end of the picture. The receiving end takes the callsign data and fills in the ID field on the user's screen. I don't know what the FSK parameters are, but it seems to me that the foundation is in place for an APRS-formatted FSK packet to be appended to the end of the SSTV picture...or, heck, even a standard 1200 baud AX.25 APRN stamp. Someone would have to convince the MMSSTV software author to incorporate it. >Subject: Re: APRN the best setup >From: Bob Bruninga >Date: Sat, 7 Dec 2002 21:17:51 -0500 (EST) >Here is an IDEA I just had today. Sinec the tones for SSTV go between >1200 and 2300HZ and AX.25 packet is 1200 and 2200 Hz, then it is possible >that a short AX.25 packet can be sent within a line of SSTV! >If the shortest packet is something like WB4APR>MYBOAT: >Then we can send the SENDERS call and a 6 character IMAGE name in only >about 18 characters of AX.25 (or so). The original SSTV was 15 lines per >second or about 70 ms per line. SHucks, it takes about 125 ms to send >that shortest packet. Nevermind. But close... >But imagine if we could, then a TNC monitoring SSTV would show who is >sending what... >de WB4APR, Bob --Tom Weeden Amateur Radio WJ9H Madison, WI http://www.qsl.net/wj9h ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: RE: SSTV Frequency From: "Michael J. Wolthuis" Date: Sun, 8 Dec 2002 21:32:12 -0500 X-Message-Number: 16 Bob, The problem with using two meters from what I have been told is that if I run Band A on APRS (144.390) and use Band B for SSTV (VC-H1) on a 2meter freq. then the two will not coincide very well because they have to wait for each other to transmit and then when SSTV is TX no APRS data is available on RX either. This was info from one fellow ham that I got, the VC-h1 is not here in my hands yet so I can not really attempt anything, plus I have to build a receiver station yet. I was told if I run it on UHF on Band B that they can coincide with each other. Then I can pull my APRS position off of the national feed to overlay with the picture received on the SSTV freq. One other thing confuses me, when you talk about repeaters, can SSTV go through a standard voice repeater? I didn't think so, but maybe I am wrong. If so, why not build a HIGH UHF machine for SSTV? Just still trying to figure everything out. Everyone's input surely helps! Mike Wolthuis Kb8zgl President Michigan State Univ. Amateur Radio Club -----Original Message----- From: Bob Bruninga [mailto:bruninga@usna.edu] Sent: Sunday, December 08, 2002 9:19 PM To: Mike Wolthuis Cc: TAPR APRS Special Interest Group Subject: Re: [aprssig] SSTV Frequency On Sun, 8 Dec 2002, Mike Wolthuis wrote: > Group, > With all these new thoughts on APRN and SSTV I am very interested and can > not wait to play more. I have some really good ideas now to make this work > really well, but from everything I can tell it has to be done on a seperate > frequency from APRS, which is what I figured. > > So, my question is, what is the UHF frequency, if there is one, that has > been dedicated to this form of SSTV? Also, I read something about an SSTV > repeater. Do these exist on UHF in some states? I really want to find one > frequency and stay on that so I can have multiple SSTV receivers around my > state using APRN and have the same if travelling to other states that use > this concept. > > Is UHF the place to do it? If not, what else may be? Any HF? 2 meters has lots and lots of unused spectrum. We have 100 repeaters in the baltimre washington DC area on the books, but scanning the band during monrning rush hour and you might hear 4 of them in use.... bob > > Thanks everyone, > Mike Wolthuis > kb8zgl > > --- > You are currently subscribed to aprssig as: bruninga@usna.edu > To unsubscribe send a blank email to leave-aprssig-28336O@lists.tapr.org > Questions regarding the SIG go to the SIG administrator: wa1lou@tapr.org > de WB4APR@amsat.org, Bob PCsat WEB page http://www.ew.usna.edu/~bruninga/pcsat.html ISS-APRS FAQ: http://www.ew.usna.edu/~bruninga/iss-faq.html CUBESAT Designs http://www.ew.usna.edu/~bruninga/cubesat.html APRS LIVE pages http://www.ew.usna.edu/~bruninga/aprs.html APRS SATELLITES http://www.ew.usna.edu/~bruninga/astars.html MIM/Mic-E/Mic-Lite http://ssdl.stanford.edu/mims/ ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: RE: SSTV Frequency From: Roger Grady Date: Sun, 08 Dec 2002 22:05:23 -0500 X-Message-Number: 18 At 09:32 PM 12/8/02 -0500, Michael J. Wolthuis wrote: >One other thing confuses me, when you talk about repeaters, can SSTV go >through a standard voice repeater? I didn't think so, but maybe I am >wrong. If so, why not build a HIGH UHF machine for SSTV? SSTV will go through a voice repeater just fine. There's nothing in it outside the voice bandpass. Some repeater groups/trustees might take issue with SSTV on their repeater (which is certainly their right to do) but that's a political issue, not a technical one. Roger Grady K9OPO ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: RE: SSTV Frequency From: kb2scs@optonline.net Date: Sun, 08 Dec 2002 22:17:02 -0500 X-Message-Number: 20 Hi Michael Yes SSTV works through regular voice repeaters. There is just two things you have to do first. Number one is the most important. 1) Get repeaters owners permission first. 2) Key the pit switch on the side of the vh-c1 first. What you want to do is bring up the repeater before you transmit your picture. You would normally key the vh-c1 pit button announce your callsign then release the pit button then immediately push the vh-c1 picture transmit button. Most repeates have a delay when they are first keyed. You have heard the effect when the first characters of a Hams transmission are clipped because they started talking before the repeater has completely come up. By doing what I have suggested you will not lose the first bytes of your SSTV transmission. On 8 Dec 2002 at 21:32, Michael J. Wolthuis wrote: > Bob, SNIP One other thing confuses me, when you talk about repeaters, can SSTV go > through a standard voice repeater? I didn't think so, but maybe I am > wrong. If so, why not build a HIGH UHF machine for SSTV? > > Just still trying to figure everything out. Everyone's input surely > helps! > > Mike Wolthuis > Kb8zgl > President Michigan State Univ. Amateur Radio Club > Let us hope we never witness the "Silence Of The Hams" 73 DE John KB2SCS Mail To: kb2scs@wa2pnu.#nli.ny.usa.noam E-Mail: kb2scs@arrl.net ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: RE: SSTV Frequency From: "Gregg G. Wonderly" Date: Sun, 08 Dec 2002 21:22:51 -0600 X-Message-Number: 22 >Most repeates have a delay when they are first keyed. You have heard the >effect when the first characters of a Hams transmission are clipped because >they started talking before the repeater has completely come up. More often then not, it is the fact that you are using CTCSS, and your radio is slow to unsquelch. I have a scanner on a local linked repeater system. I always hear everything said on the scanner, but there is a full second if not two delay on the TH-D7 before the squelch opens on it... ----- gregg@cytetech.com (Cyte Technologies Inc) ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: RE: SSTV Frequency From: Bob Bruninga Date: Sun, 8 Dec 2002 22:30:41 -0500 (EST) X-Message-Number: 23 On Sun, 8 Dec 2002, Michael J. Wolthuis wrote: > The problem with using two meters from what I have been told is that if > I run Band A on APRS (144.390) and use Band B for SSTV (VC-H1) on a > 2meter freq. then the two will not coincide very well because they have > to wait for each other to transmit and then when SSTV is TX no APRS data > is available on RX either. You QSY the A side (APRS) to the SSTV uplink frequency for the 40 seconds it takes to do an SSTV uplink. The other 99.99% of the time it stays on 144.39. The only time you need to uplink an SSTV picture is when you see a fire, a Wreck, a Terrorist of whatever... Remember, your ARPS packet on the SSTV uplink frequency tells the APRSN system who is sending the picture... Bob ---