E(gg)xtras - Accessories for Eggtimer / Eggfinder

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sl98

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During the recent Black Friday, I purchased a TRS and a couple of the flight computers to go with my older Rev C boards. I noticed several posts in various threads of accessory items that I may use when I start building. Unfortunately, all of these suggestions are scattered in different threads. I'm not vouching for any of these ideas but I thought it might be helpful to get them in one thread. You should be able to use the links to go to the original thread and the source that was posted in the original thread. I'm sure I missed some. If you are aware of things I missed post a reply with a link to the post and I'll try to add it to the table below.




The above table is not an exclusive list. There are additional items that are discussed in the thread below. The links provided were copied from the referenced posts. Use caution and verify the item is correct before buying.
 
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Yes thanks. What a lot of people look for and don't know if they will work or not. Very useful :)
 
I seem to remember a "patch" antenna that might be useful for mounting on a pole for a longer range receiver base station.
 
I seem to remember a "patch" antenna that might be useful for mounting on a pole for a longer range receiver base station.

https://www.streakwave.com/itemdesc.asp?ic=ARC-PA0910B01&eq=&Tp=

The patch antenna is heavy and not amenable to triapsing out to the downed rocket. If used, best to disconnect and put a duck antenna on the receiver to
take to the last known packet.

Linx technologies 1/2 wave antenna: https://www.linxtechnologies.com/resources/data-guides/ant-916-cw-hw.pdf
Same with 1/4 wave: https://www.linxtechnologies.com/resources/data-guides/ant-916-cw-qw.pdf Google for a sale source.

Something like this might be considered for a base monitoring station as opposed to a patch antenna: https://www.ebay.com/itm/900-1800MH...ectional_Network_Antennas&hash=item35de1b3656

Don't completely discount a Yagi antenna. It does indeed have a narrow pattern but once the rocket has landed, it could give and extra edge trying to receive
new packets from a rocket that has landed quite a distance away and in the undergrowth. This should be "last" on the list of a sport flyer and might not be needed. https://www.ebay.com/itm/900Mhz-GSM...ectional_Network_Antennas&hash=item3f2678c00a (Would need to get an extension cable if going to use.)

The jumper cables listed above are good to actually use the stock provided plastic case work in a vertical fashion:

https://www.ebay.com/itm/40pcs-20cm...tDomain_0&hash=item27e2828fc7&afsrc=1&afsrc=1

A 4" version of this cable is adequate: https://www.ebay.com/itm/cable-RP-S...onnectors&hash=item3f2eb8c2e1&afsrc=1&afsrc=1

Can get it to look like this: https://www.rocketryforum.com/showt...for-Eggfinder-GPS-Tracker&p=739782#post739782

Can fit this 2100mah pack: https://www.hobbyking.com/hobbyking...2100mAh_2S3P_Receiver_Pack_US_Warehouse_.html

Kurt
 
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Also requires an RP-SMA to N connector or cable, which was not as readily available as I had imagined.

Sure there are:

https://www.ebay.com/itm/RP-SMA-to-...ectional_Network_Antennas&hash=item19d459b958

I had a bunch of SMA board connectors so my cable needs are different. This is what I use because of it:

https://www.ebay.com/itm/cable-N-ma...Coaxial_Cables_Connectors&hash=item4173649830


The RP-SMA needs the first one. Look on ebay and get the length you want. I don't recommend trying to carry the
patch antenna around. It's a heavy thing. Use it for a base station and plug in a more portable antenna to proceed to the recovery site. If one is just flying
a sport rocket, the patch antenna is probably superfluous. If really pushing the altitude above 10k' with a lot of expected drift, might be helpful. Kurt
 
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L-Com has a number of antennas for the various frequency bands we use in rocketry.

https://www.l-com.com/wireless-ante...|14927168331&gclid=CJDpjJSQxMICFWho7AodIDEAGQ

A moderate gain patch antenna pointed skyward mounted on a pole or tripod works great to downlink data or video from a rocket. Patch antennas are available with linear or circular polarization. There are s/n advantages if you choose to use a circularly polarized antenna in the rocket and the ground station, however you need to make sure both the transmitting and receiving antennas have the same polarization.

Bob
 
L-Com has a number of antennas for the various frequency bands we use in rocketry.

https://www.l-com.com/wireless-ante...|14927168331&gclid=CJDpjJSQxMICFWho7AodIDEAGQ

A moderate gain patch antenna pointed skyward mounted on a pole or tripod works great to downlink data or video from a rocket. Patch antennas are available with linear or circular polarization. There are s/n advantages if you choose to use a circularly polarized antenna in the rocket and the ground station, however you need to make sure both the transmitting and receiving antennas have the same polarization.

Bob

For the 70cm Ham Band, I think Jim Jarvis posted this link to this antenna:

https://www.antennas.us/store/p/390-UC-4364-513-UHF-Amateur-Satellite-Antenna-with-built-in-LNA.html

I suspect this would be the Rolls-Royce for the Beeline APRS/GPS tracking set. I think Jim had a 118,000' flight at an LDRS a short while back so I suspect he would have needed all the range he could get out of a system. :wink:

Streakwave has a $13.95 patch antenna that will work with the EggFinder ISM frequencies previously discussed here along with others: https://www.streakwave.com/items.asp?Cc=ANT900FP&iTpStatus=0&Tp=&Bc=

This is the parent page to the one I posted above.


Kurt
 
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For the 70cm Ham Band, I think Jim Jarvis posted this link to this antenna:

https://www.antennas.us/store/p/390-UC-4364-513-UHF-Amateur-Satellite-Antenna-with-built-in-LNA.html

I suspect this would be the Rolls-Royce for the Beeline APRS/GPS tracking set. I think Jim had a 118,000' flight at an LDRS a short while back so I suspect he would have needed all the range he could get out of a system. :wink:

Streakwave has a $13.95 patch antenna that will work with the EggFinder ISM frequencies previously discussed here along with others: https://www.streakwave.com/items.asp?Cc=ANT900FP&iTpStatus=0&Tp=&Bc=

This is the parent page to the one I posted above.


Kurt
Jim's antenna is good, but large and expensive. It's great for receiving weak signals at a base station location but you wouldn't want to be humping it around in the field. Jim used a real-time tracking system so he knew the location of his rocket was with 100 meters or so at all times it was in line of sight of the receiver. I'm sure he projected where it landed and drive out close to it and then hiked with GPS guidance to get close enough to pick it up on a handheld. ARPS is good enough tracking balloon flight that if you have an audible beeper in your payload, the last transmitted GPS location gets you close enough to hear the beeper.

There a literally thousands of suitable 900 MHz ISM antennas. The one you suggest costs about half as much as the one I suggested after you include the price of the antenna cable and connector. The one I suggested comes with the antenna cable and connector of your choice attached and weighs half as much. Both should work fine for an EggFinder.

Bob
 
Actually, I use an eggbeater.

It worked pretty well in 2011. The transmit rate was every 10 seconds, and most packets were collected (flight ended about 8 miles out). However, during another flight, there was more data missed, so we added an AMSAT/ARRL preamp to the system. Unfortunately, there was a bad part in the preamp, and in 2013, data collection was reduced. Fortunately, I had later coordinates from my handheld, so it was no problem locating the rocket. Everything worked well this year with the pre-amp fixed, except that I didn't get a high altitude flight to demonstrate it.

Jim

IMG_3326.JPG

Balls 2011 GPS Graph PNG.jpg

telemetry.jpg
 
I know of 2 guys who fly at BALLS that have beacons out on the playa to help receive the signal.


JD
 
Maybe a dumb question. Can I cut one end of this cable off, strip the insulation/shielding and use it for a "wire" antenna on my EF TRS when I don't have room for a rubber ducky antenna? Is there a better/simpler way?

WiFi Antenna EXTENSION Cable/Lead Wireless RP SMA male to female 20 inch 50cm US
https://www.ebay.com/itm/WiFi-Anten...ectional_Network_Antennas&hash=item20f181c8c6

Thanks.
NikeMikey

Ummm,

You don't want all-thread running next to the antenna. You can run a shorter version of that cable to the bulkhead and screw an antenna like this to it:
https://www.linxtechnologies.com/resources/data-guides/ant-916-cw-qw.pdf

Or even get a flexible extension cable and run it along the drogue shockcord from the bulkhead socket:

https://www.ebay.com/itm/RP-SMA-mal...871?pt=LH_DefaultDomain_0&hash=item4d2787cc47

Your antenna would be clear and out in the open at apogee then.

Look at picture #2 here:

https://www.rocketryforum.com/showt...for-Eggfinder-GPS-Tracker&p=739782#post739782

See the short cable that goes from the EF receiver board to the outside of the plastic case? The case would be the bulkhead and you could attach a short antenna there if it is the aft bulkhead or screw in another short extension cable to tape to the shockcord and screw a small antenna into it. You could have the antenna in the forward bay if you prefer as long as you protect it from the
powder flash of the BP. A cardboard tube with a wrap of duct tape works. Your bays need to be radio lucent. No carbon fiber or
metallic paint.

If you can fit your TRS wire antenna far enough forward into your main chute bay, you could put a stiff plastic tube stent over the wire antenna so it doesn't get squished by the main chute being thrown aft under acceleration. You'd simply drill a form fitting hole in the bulkhead for the antenna to project through and seal with clay. I'm doing that with a Beeline GPS tracker in a small rocket and it works perfectly fine. You don't want the antenna to get smushed down and deformed.
Won't radiate well. Kurt
 
Thanks. I had ordered the extension cables. I was looking for a way to mount a wire antenna to the bulkhead fitting. I was wondering if I could use a second extension cable (with the end cut off) that had been stripped down to bare wire over 80mm of its length. It looks like the 1/4-wave antenna you suggest would be a better solution.
NikeMikey
 
I actually tried that during development of the Eggfinder, it really doesn't work that great because there's no ground counterpoise. I also tried stripping the braid back a little and soldering a 80mm length of brass tubing over it and the jacket to work as a dipole counterpoise, it was better but by the time you go to all that trouble you might as well just get one of the Linx antennas and be done with it.
 
I actually tried that during development of the Eggfinder, it really doesn't work that great because there's no ground counterpoise. I also tried stripping the braid back a little and soldering a 80mm length of brass tubing over it and the jacket to work as a dipole counterpoise, it was better but by the time you go to all that trouble you might as well just get one of the Linx antennas and be done with it.

Thanks I just ordered a couple of these for $7 each from Mouser.

https://www.mouser.com/Search/Produ...virtualkey59000000virtualkey712-ANT-916-CW-QW

NikeMikey
 
Think I have most of the accessories listed in the first post, but ordered a 10-pack of the screw terminals to retro fit the two eGGtimers that CaveDuck assembled for me.

My first eGGtimer the terminal pins worked great, but the wires in the slide on plugs/blocks were not infield friendly wires backing out and coming loose from the connnectors .. and not conducive to the way I do sleds now..one wire one hole style. The second eGGtimer we did 'lead wires' hanging out and the small 1s mini jst wire broke at the attachment point and the terminal blocks will eliminate that issue.

If they survive my R&R (will do lead wire one first) - may update one or both to 9v operation , i really hate those mini/micro JST whips .

Kenny
 
Think I have most of the accessories listed in the first post, but ordered a 10-pack of the screw terminals to retro fit the two eGGtimers that CaveDuck assembled for me.

My first eGGtimer the terminal pins worked great, but the wires in the slide on plugs/blocks were not infield friendly wires backing out and coming loose from the connnectors .. and not conducive to the way I do sleds now..one wire one hole style. The second eGGtimer we did 'lead wires' hanging out and the small 1s mini jst wire broke at the attachment point and the terminal blocks will eliminate that issue.

If they survive my R&R (will do lead wire one first) - may update one or both to 9v operation , i really hate those mini/micro JST whips .

Kenny

Yeah, with the terminal blocks it's easy to test and replace wire ends whereas with enough movement on a soldered pigtail, it will eventually snap off at the board and one will have to desolder and clear out the hole and hope they don't strip off the pad in the process.

A comment on a plain wire antenna at the bulkhead. I'd worry about a thin wire antenna getting bent out of shape too much to be an effective radiator.
A 1/4 Linx antenna attached to a cable taped/secured to the apogee shockcord is a good solution. Kurt
 
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When I bought the kit I asked for all the extras; USB cable and those terminal blocks.
I haven't been able to put it together yet as: I have no experience soldering SMT parts.
Have to wait for some free time to open up so oneblackhawk can help me.

JD

I don't suppose anyone could add the term blocks for the Eggfinder TRS?
 
I successfully used this bluetooth module on my EF Rx. My Samsung S4 had no problem talking to it.

https://www.banggood.com/HC-06-Wireless-Bluetooth-Serial-Transceiver-Module-Slave-p-908617.html

A variety of Android apps can parse the data. "Bluetooth GPS Provider" and "Bluetooth GPS" can provide information about the nature of the
fix, number of satellites, WAAS vs GPS, connection etc from the packets coming in from your EggFinder or TRS. Your Android device has to to be set to "Enable Mock GPS Provider". "GPS Rocket Locator" can give to points and a datum line. Nice when it works. I've sometimes noticed it lockup and shutdown. That's where the lat/long comes in for backup on the EggFinder LCD screen. Can either go to another location
app on your Android device or use a handheld mapping GPS. I have an old Etrex Vista HCX that I set for decimal degrees and can simply input the lat/long. Will navigate one to the coordinates with a datum line and specfics like ETA and such.
The Ham Radio APRS trackers have just a "little" edge over the EggFinder but the EF costs like $400 to $600 LESS than a comparable ham
setup that will do portable realtime tracking/navigation on a map. It's not worth the extra bux for a sport flyer to find a rocket. The utility of the EF system is pretty darned good. Kurt
 
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