We got any local Hams going to LDRS? A question.

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cvanc

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I have an older Walston and all the transmitters are down at 219.nnn. Any comments on using those freqs at your field? Thanks.
 
There should be no issue with using 219 - 220 for digital transmission. Although we are secondary users there, I am not aware of any primary services near our field using that segment of the band, so you should be good to go. Most fliers will be using 440 and above.
We will have an erasable white board at the RSO table for folks to list their frequencies in use pre launch in an effort to help prevent fliers from tracking the wrong bird/dealing with avoidable interference. We will ask fliers to delete their frequency information ASAP post flight/recovery to open the frequency to other fliers.
Greg
 
I do have a tracker that runs at about 218MHZ. An older device used to track birds. The only down side is the size of the antenna.
 
My reading of the Ham allocation indicates that CW transmission is technically not allowed by hams from 219-220 Mhz.

Plus you're supposed to notify the nearest AMTS station (where ever they are 30 days before transmitting ) if your less than 398 miles from one. NY/Conn coast is less than 398 miles from Potter. However I doubt that a few milliwatts at 10000 feet could possibly interfere with a coastal AMTS station.

https://www.arrl.org/frequency-allocations
 
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Crazy Jim will be there, biggest ham I know...

Chad, you going? Be fun to have some one else to pick on besides Al.

I do have 3 Marshall Falcon freq. in the 219 band . I'll be using....off hand 219.386... 219.486 have to dig out the 3rd.
 
LOL, I need to get my ham license so I can use my telemetrum! From what I've studied so far seems impossible.....

Really? The Tech test is not that bad. Read the book. Memorize as many questions as you can as they are online and it's a piece o' cake. I studied for about 4 months and did the Tech and General at one sitting. Did better on the General than the Tech but passed both. You just need the Tech to do the 70cm tracking. Get that Tech ticket and other options are out there.

The cost of APRS is dropping though not as economical as the EggFinder as you know. The SainSonic is a 1 watt GPS tracker/tranceiver that shows promise for rocket locating: https://www.radioddity.com/us/avrt5...th-thermometer-tf-card-support-aprsdroid.html

1 watt on the 2 meter band, tunable, probably only for 4" or larger diameter projects due to size. It will store the track in a .KML file on a micro SD card for later download. B/T compatible too so technically, since it's a transceiver, if one bought two of them, could use one for the receiver and bond it to an Android device and use APRSDroid and OSM maps for "off grid", no internet required, GPS tracking on a map. A cheaper receive station would be a Mobilinkd TNC: https://store.mobilinkd.com/ one can plug into any Ham handi-talkie and bond it to an Android device to use APRSDroid for on map tracking. Oh, it will telemeter the temperature of the device (a temp chip is on the board so it measures the heat production of the unit under power not the external temp) and the real time voltage.
So one can have a live "OnAir" report on the device health. I've run the thing all day long without issue.

Only downsides to it. Sirf 4 chipset so GPS altitude will likely be off and unacceptable to be considered for altitude record attempts above 30,000 feet. Lat/Long is perfectly fine. The instructions absolutely, positively stink. The user group has all the info to use and it's not that bad of a learning curve. Just leave out the micro SD card to program or it won't connect and one has to use the provided USB/serial cable. When done programming, slide the micro SD card back it. It uses APRS so it won't work with the Android program: "GPS Rocket Locator".

Sooooo. For a higher powered APRS tracker one can get going for a bit less than $200.00 not including an H/T (AP510 and Mobilinkd B/T TNC. More if you have to buy an Android device). If a flyer is already a Ham with a VX8/FT1D series or D7/72 radios they just have to shell out for the AP510. If one is interested, there is a U-tube video that can be searched for for programming details and the latest programming software and firmware is at that first link above.
Scroll down and click on "downloads" and then download the file at "AP510 APRS Software". Change the name and put .zip on the end and the files will unpack. I virus checked and it's clean. Or search online. You'll not find anything more recent. I'll probably be looking to Ebay away some of my older Byonics trackers in the future. Kurt
 
My reading of the Ham allocation indicates that CW transmission is technically not allowed by hams from 219-220 Mhz. Plus you're supposed to notify the nearest AMTS station (where ever they are 30 days before transmitting ) if your less than 398 miles from one. NY/Conn coast is less than 398 miles from Potter. However I doubt that a few milliwatts at 10000 feet could possibly interfere with a coastal AMTS station. https://www.arrl.org/frequency-allocations

Since this can has been opened - quoting from the referenced site: "This allocation is only for fixed digital message forwarding systems operated by all licensees except Novices. Amateur operations must not cause interference to, and must accept interference from, primary services in this and adjacent bands".

Obviously we are dealing with dated information since the Novice category doesn't exist anymore. Anyway as we are dealing with data transmission, one could certainly make the argument we are dealing with digital messages being forwarded to a receiver. Remember that CW in essence is digital being on or off (1 or 0). As long as the rocket is on the pad, and once it's back on the ground it would qualify as a fixed forwarding system, now wouldn't it? We'll just make sure it doesn't transmit while in motion! ;) :)
 
Good argument! Also try and find locations of AMTS stations on the internet. I searched and found nada.
 
Actually, the Novice class does exist and there are 13,565 of them as of today.

As of April 15, 2000, the FCC no longer issues new Novice class licenses. Current Novice licenses remain valid, and can be renewed indefinitely.
 
Actually, the Novice class does exist and there are 13,565 of them as of today.

As of April 15, 2000, the FCC no longer issues new Novice class licenses. Current Novice licenses remain valid, and can be renewed indefinitely.

Yup. If the holders want to renew it until they die, they can. Kurt
 
I find it interesting so many still exist as they all were given the opportunity to upgrade to tech plus, by passing the tech written exam.
With the elimination of the code requirement tech plus doesn't mean anything now, but at the time it did.
That's the approach my then 10 year old daughter took.
 
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