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JordanT said:
Of course, you can put the coordinates into Google Earth...but if you're in the middle of nowhere AND you didn't bother to bring a mapping application (like NAVTEC or any of the hiking apps which include/offer offline topo maps), then you can go low tech and get the app Free GPS, which looks like this to put your PacketPad data into. Then just follow the arrow to the rocket location.
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Jordan - I can't find the same app you showed, and it looks quite nice. Is there anything more to the name that might make it easier to search for?
 
beezwax said:
Well the "Ham Whisperer" study guide worked for me! I took the Technician exam today and got a perfect score, though the only thing that really proves is I can cram a lot of stuff into short-term memory. I ran through the entire 396 question pool twice this morning before the exam and didn't miss a single one so I knew I was ready...but to be honest I don't know what half the questions actually mean, I just memorized the right answers. The funny thing is the examiner gave me my results, then suggested I take the General exam since I could do it right then and it wouldn't cost any more than the fee I'd already paid, and I said Uh..........sure why not? I hadn't seen any of the questions and had no idea what was on the exam, so I was expecting to fail it miserably. But I got 20 out of 35 correct, still 6 shy of actually passing it but if nothing else I think I've learned how to interpolate for the sake of the FCC testing. Anyway now that the hoops are jumped I can get back to business and use these new powers to fight evil, and find rockets. Chris how are your studies going?
Click to expand...

Things went very well. I took the exam Jan 19th, and passed both the technician and general tests, and was five questions from passing the extra. Now I'm just waiting for my callsign...
 
AndyC said:
Jordan - I can't find the same app you showed, and it looks quite nice. Is there anything more to the name that might make it easier to search for?
Click to expand...

It really is called Free GPS...put that in the App Store search bar and it will be about the fourth app in. The cover image looks a lot like the compass screen shot I posted.
 
RadManCF said:
...passed both the technician and general tests, and was five questions from passing the extra...
Click to expand...

Wow that's awesome, well done! You took all three exams at once!? My brain was maxed out with just the Tech question pool, I'd need to take a class or join a club if I wanted to have any real understanding of this stuff. Maybe the desire will grow from this one day but for now it just felt like jumping through hoops. I'm waiting for a call sign too, well that and I need to collect a bit more kit before I can give RDF a try...
 
beezwax said:
Wow that's awesome, well done! You took all three exams at once!? My brain was maxed out with just the Tech question pool, I'd need to take a class or join a club if I wanted to have any real understanding of this stuff. Maybe the desire will grow from this one day but for now it just felt like jumping through hoops. I'm waiting for a call sign too, well that and I need to collect a bit more kit before I can give RDF a try...
Click to expand...
So, do you have an HT yet?
 
RadManCF said:
So, do you have an HT yet?
Click to expand...

Yes actually I just picked up a Baofeng UV-3R (the Mark 2 version which takes normal SMA-male antennas, rather than the versions which came before and after which for some reason are reversed and need SMA-female antennas like Wuoxon radios). I'm hoping it will work well enough for RDF tracking. I'm sure it isn't as nice as a Yaesu or Kenwood etc, but on the other hand it only cost me $36 shipped, and I have no intention of using it for anything else but this so I don't want to spend more unless I have to. I have a Tele-mini which I picked up from Altus Metrum during their Black Friday sale, though I still need to get their PC interface. And I ordered a BNC cable and BNC-SMA adapter on eBay for next to nothing, which hopefully will also prove usable (no surprise it's coming from China). But I still need to order a yagi and I suppose an offset attenuator (which folks seem to really recommend) which I plan to do from Arrow, though of course that's a bigger chunk of change. Have you assembled a working kit?
 
beezwax said:
Yes actually I just picked up a Baofeng UV-3R (the Mark 2 version which takes normal SMA-male antennas, rather than the versions which came before and after which for some reason are reversed and need SMA-female antennas like Wuoxon radios). I'm hoping it will work well enough for RDF tracking. I'm sure it isn't as nice as a Yaesu or Kenwood etc, but on the other hand it only cost me $36 shipped, and I have no intention of using it for anything else but this so I don't want to spend more unless I have to. I have a Tele-mini which I picked up from Altus Metrum during their Black Friday sale, though I still need to get their PC interface. And I ordered a BNC cable and BNC-SMA adapter on eBay for next to nothing, which hopefully will slso prove usable (no surprise it's coming from China). But I still need to order a yagi and I suppose an offset attenuator (which folks seem to really recommend) which I plan to do from Arrow, though of course that's a bigger chunk of change. Have you assembled a working kit?
Click to expand...

I'm in the process, I've got a Yaesu FT-60, which also uses an sma antenna. I built a J pole antenna, which is an omni directional antenna. I haven't gotten around to making a Yagi as of yet. No attenuator yet either, but I've done some reading, and it looks like a good DIY item. The advantage to using an offset atennuator is that it shifts the frequency of the recieved signal. Oftentimes, when doing RDF, once you get close to the transmitter, the signal is so strong that the radio starts recieving the signal through the connection between the antenna and the reciever, inside the case. Once that happens, any external atennuator is useless. Since an offset atenuator shifts the signal's frequency, the reciever must be tuned to a frequency different from that of the original signal, thereby avoiding the problem. BTW, 1/2in copper pipe makes good antenna elements. Good electrical properties, and very lightweight. The J pole I built is about six feet tall, but is light enough that carrying it upright while hiking is not uncomfortable.
 
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Those are all good tips, thank you (and sorry for completely derailing your thread with discussion of exams and general kit, I know this was supposed to be about APRS). I can certainly see that antennas and even attenuators could be good DIY projects if you're handy with electronics, but I think I will probably still suck it up and just purchase those two items. Since I am still basically scratching my head about this whole process even though the license requirement is out of the way I think I should avoid the potential for compounding errors and not try to make my own antennas etc yet. I want to learn how to actually use these items successfully first before I go trying to build my own.
 
beezwax said:
Those are all good tips, thank you (and sorry for completely derailing your thread with discussion of exams and general kit, I know this was supposed to be about APRS). I can certainly see that antennas and even attenuators could be good DIY projects if you're handy with electronics, but I think I will probably still suck it up and just purchase those two items. Since I am still basically scratching my head about this whole process even though the license requirement is out of the way I think I should avoid the potential for compounding errors and not try to make my own antennas etc yet. I want to learn how to actually use these items successfully first before I go trying to build my own.
Click to expand...
Oh, don't worry too much, this thread never really went in the intended direction. And I can understand not wanting to compound errors. If it's any encouagement, if you build your own Yagi, the most electronically involved part of the project will be stripping the coax, seperating the conductors, and attatching them to the driven element. For 1/2in or larger pipe, hose clamps work great. So, are you still waiting for your callsign?
 
If I was going to scratch build anything it would certainly be the yagi. I can see that there's really not much to the antenna, probably the only critical part would be to keep the arm lengths and locations precise? Unlike an offset attenuator which looks like a much more involved build! I just checked my FRN again, still comes up blank...not sure how long the FCC takes to process new call signs but I guess there really is no need for urgency on my part. Do you have your very own string of letters and numbers yet?
 
beezwax said:
If I was going to scratch build anything it would certainly be the yagi. I can see that there's really not much to the antenna, probably the only critical part would be to keep the arm lengths and locations precise? Unlike an offset attenuator which looks like a much more involved build! I just checked my FRN again, still comes up blank...not sure how long the FCC takes to process new call signs but I guess there really is no need for urgency on my part. Do you have your very own string of letters and numbers yet?
Click to expand...
I'd say the most critical part of building a Yagi is to make sure that the driven element is insulated from the other elements. I've been surprised by my J pole- it's sized for the 2m 144-148Mhz band, but it picks up the 108-137Mhz airband, the 70cm HAM band, and the NOAA weather radio stations in the neighborhood of 162Mhz as well. I still don't have my callsign yet either. There's some interesting history behind the process. Around 1980, regularory agencies were generally facing massive budget cuts. One of the FCC's cost cutting measures was to push the HAM radio licensing process off onto volunteers, kind of like our process for HPR certs. Under the current scheme, there are fourteen organizations acreddited as Volunteer Examiner Coordinators, af which ARRL is one. If you take the test at an ARRL session, the paperwook all gets funneled through their headquarters in Newington, Connecticut, and from there, given to the FCC. From what I've heard, the VEC's can be a bottleneck.
 
Gotcha, well I did a walk-in for the exam portion of a class that was being offered by a local club (I didn't have time to take the whole class, just sat the exam with the other students) but I don't think it was an ARRL session. No matter though, it'll be processed eventually and if something gets lost in the shuffle I have the little certificate they gave me for backup :) I'm really surprised that your j-pole is picking up all those different bands but I guess I don't understand radio mechanics enough to know why that's happening!?
 
beezwax said:
:) I'm really surprised that your j-pole is picking up all those different bands but I guess I don't understand radio mechanics enough to know why that's happening!?
Click to expand...


Not really surprising,, more like expected. Any ol piece of wire will receive heaps of frequencies. You need to worry about resonance when you transmit. Just receiving APRS data and decoding it you could use the above antenna or the rubber duck the radio came with. Just remember to transmit only on a resonant (or close to) antenna.
 
That's pretty cool! Thank you for sharing that link for the DIY yagi, I just read through it and it sure sounds simple enough. Maybe I will give it a try... :)
 
Last year, I took my test from AARL on a Saturday. I showed up in the database two Wednesdays later (11 days).


All the best, James
 
Finally got my callsign, I'm KD0UFC. I'm ammused by the suffix; I'm not a fan of UFC, but still, what are the odds? Also, eham.net is a good place to look for links to antenna designs. One I found rather interesting was called a J beam, which is essentially a cross between a J pole and a Yagi. The dimensions given in the link are for a 2m antenna, but it does include formulas for calculating dimensions for other bands.
 
Nice! Mixed martial and radio arts, you can use your street fighting and "fox hunting" skills to find your rockets...you know, if your launch site is also home to bears or aggressively territorial squirrels :)
 
Sorry everybody, My disclaimer to not transmit was insufficient. Thank you for pointing out that the resonant transmitting frequency is 2m on that plan I posted BRB. It would still work for just receiving packet data though just don't transmit.


V2rocketeer said:
Not really surprising,, more like expected. Any ol piece of wire will receive heaps of frequencies. You need to worry about resonance when you transmit. Just receiving APRS data and decoding it you could use the above antenna or the rubber duck the radio came with. Just remember to transmit only on a resonant (or close to) antenna.
Click to expand...
 
RadManCF said:
Finally got my callsign, I'm KD0UFC. I'm ammused by the suffix; .
Click to expand...

Hey Chris,,

welcome to Ham radio I am VK2ICJ. Your suffix could be "Unidentified Flying Contraptions"

Now I will try and convince you to learn the code (wink)

73 de vk2icj sk..
 
V2rocketeer said:
Hey Chris,,

welcome to Ham radio I am VK2ICJ. Your suffix could be "Unidentified Flying Contraptions"

Now I will try and convince you to learn the code (wink)

73 de vk2icj sk..
Click to expand...

So, that last line translates as: "goodbye from vk2icj, a dead guy". Or does sk mean somthing other than silent key?
 
RadManCF said:
So, that last line translates as: "goodbye from vk2icj, a dead guy". Or does sk mean somthing other than silent key?
Click to expand...


When sending the final tranmission in morse code you follow your call with SK which does mean silent key because you are not transmitting anymore,,, hence the term silent key also being used to described a ham who has passed on. The 2 dots after the sk are not sent as "periods" or full stops but as dits..

Since I am replying to this lol I should have used KN istead of SK which means "go ahead" "over" or "back to you" SK is for the last transmission only.

:cyclops:

so

KD0UFC KD0UFC de VK2ICJ FB OM KN
 
RadManCF said:
So, that last line translates as: "goodbye from vk2icj, a dead guy". Or does sk mean somthing other than silent key?
Click to expand...
He meant the prosign "dih-dih-dih-dah-dih-dah" (with no space). There's no character set that will put a bar over the "SK", is there? I tried using underbar on the line above, but the spacing gets compressed and that doesn't work either.
 
Darnit, you guys have sucked me into the HAM radio world. I got a study guide called " The No-Nonsense Guide to Taking the Technician Class Exam" and then found the practice tests on the eham.net site. After 2 tests, I'm up to the 85% level which indicates I'll likely pass it....... Now the local Hamfest is on March 8th or so, and I'll go take the exam then. I just downloaded the same Guide to the General exam, but don't know if I can be ready for that one too.

So after you get the License, and then buy a Yaesu VX-8GR with the GPS in it, and the Telemetrum unit for the rocket, then you need a cable to go to a laptop that will show the Google Earth map of your rocket flight? That sure is a lot of money to track a rocket.:y:
 
hobie1dog said:
Darnit, you guys have sucked me into the HAM radio world. I got a study guide called " The No-Nonsense Guide to Taking the Technician Class Exam" and then found the practice tests on the eham.net site. After 2 tests, I'm up to the 85% level which indicates I'll likely pass it....... Now the local Hamfest is on March 8th or so, and I'll go take the exam then. I just downloaded the same Guide to the General exam, but don't know if I can be ready for that one too.

So after you get the License, and then buy a Yaesu VX-8GR with the GPS in it, and the Telemetrum unit for the rocket, then you need a cable to go to a laptop that will show the Google Earth map of your rocket flight? That sure is a lot of money to track a rocket.:y:
Click to expand...


Ham radio is what brought me back to rocketry in the 90's. Ham radio has so many little niches of interesting tech.

If you are going to get the Telemetrum (I have one) then you do not need the VX8. The Telemetrum uses a proprietary protocal to exchange the data between the transmitter and the reciever not aprs. You will need the teledongle and a suitable antenna along with a computer. I use a little netbook, works a treat mate. The teledongle works like the TNC and radio in the Yaesu. The BigRedBee products use standard APRS so there you would need a radio, TNC (or a radio with a buit in TNC like the VX8),and an antenna. To the best of my knowledge you cannot directly connect a computer to the VX8 series radios to get a Google Earth display from APRS but the Kenwood TH-D72 can, so that might be an option for you. There are some micro portable TNC units that have digital displays that display decoded packets, so you could get a cheaper HT.

There are a lot of options when it comes to this..
 
I've got a study guide and have been browsing through it off and on for a little bit. Sooner or later...


Later!

--Coop
 
hobie1dog said:
Darnit, you guys have sucked me into the HAM radio world. I got a study guide called " The No-Nonsense Guide to Taking the Technician Class Exam" and then found the practice tests on the eham.net site. After 2 tests, I'm up to the 85% level which indicates I'll likely pass it....... Now the local Hamfest is on March 8th or so, and I'll go take the exam then. I just downloaded the same Guide to the General exam, but don't know if I can be ready for that one too.

So after you get the License, and then buy a Yaesu VX-8GR with the GPS in it, and the Telemetrum unit for the rocket, then you need a cable to go to a laptop that will show the Google Earth map of your rocket flight? That sure is a lot of money to track a rocket.:y:
Click to expand...
$$ is one of the reasons I prefer RDF to GPS. And I don't veiw getting sucked into the HAM world as a bad thing, just as an opportunity to fly some interesting payloads. Like an ATV transmitter, or low power 2m FM repeater...
 

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