Missile Works RTx?

Where did you get your charger and I assume you have connectors for the battery so you don't have to unscrew from the RTx. Where did you get those?

Here is a list of all the things used during testing & final use, everything I ordered came from USA shipping address & was Ok'd by Missileworks.

For battery connectors I got these, 100 or 50 pair sound like a lot, but they were so cheap. If you want less just enter JST connector in search box at top of page to find lesser quantities.

https://www.ebay.com/itm/100PCS-Bat...374190?hash=item19f26c6bee:g:gGwAAOSwPe1T9V6z

10 pair.

https://www.ebay.com/itm/USA-10-pai...872406?hash=item43b34b6856:g:PqkAAOSwa-dWqIoF


These batteries give rocket unit over 10 hrs continuous runtime. about 3.00 3.7 volt

https://www.hobbyking.com/hobbyking...ck_Walkera_V120D02S_QR_Infra_X_QR_W100S_.html

Battery I use on base.7.4 volt No room inside, I just tape to exterior, it very large. The LCD and base use more juice.

https://www.hobbyking.com/hobbyking/store/__26564__Turnigy_1500mAh_2S_25C_Lipoly_Battery.html

Turnigy charger [25.50] I got after recommendation from Jim Amos, AC or DC comes with all connectors for charging recommended batteries & cord for AC & clips for DC to car battery. You can get cigarette type power connector also.[does NOT come with] this unit is small...size of 2 packs of cigarettes.

https://www.hobbyking.com/hobbyking...put_AC_DC_45W_Digital_Balancing_Charger_.html

Are there 2 sets of leads coming off the battery? if so why? https://www.hobbyking.com/hobbyking/s...QR_W100S_.html

What is the difference in this battery? 9210000003 - Turnigy nano-tech 750mah 1S 35~70C Lipo .. https://www.hobbyking.com/hobbyking...s_Nine_Eagles_Solo_Pro_180_AR_Warehouse_.html

Brent said:

Are there 2 sets of leads coming off the battery? if so why? https://www.hobbyking.com/hobbyking/s...QR_W100S_.html

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There are two sets of leads so buyers have options. The red lead is the JST connector which is what you'll use if you buy the JST connectors referenced in Jim's post above (also what I use). The white one is a Walkera connector and is commonly use in RC toys. Use the red one and ignore the white one, it's that easy.

Brent said:

What is the difference in this battery? 9210000003 - Turnigy nano-tech 750mah 1S 35~70C Lipo .. https://www.hobbyking.com/hobbyking...s_Nine_Eagles_Solo_Pro_180_AR_Warehouse_.html

Click to expand...

They're the same battery - read the descriptions. They just ship from different warehouses. You can pay the $3.21 and get is shipped from the US in a few days, or pay the $2.99 and get it shipped from overseas and wait a few weeks.

Edit: if you make an account with HobbyKing and sign in they will usually give you an option when adding to your cart which warehouse you want it shipped from. They just need to know where you live so they can show you which is closer. I think they now have two US warehouses, in addition to their overseas options. The US warehouses will cost you more, but you'll get it much quicker.

farsidius said:

They're the same battery - read the descriptions. They just ship from different warehouses. You can pay the $3.21 and get is shipped from the US in a few days, or pay the $2.99 and get it shipped from overseas and wait a few weeks.

Edit: if you make an account with HobbyKing and sign in they will usually give you an option when adding to your cart which warehouse you want it shipped from. They just need to know where you live so they can show you which is closer. I think they now have two US warehouses, in addition to their overseas options. The US warehouses will cost you more, but you'll get it much quicker.

Click to expand...

It looks like the US AR (for Brent and me) will have lower shipping charges as well if ordering items without free shipping. If there are ways around that, please let me know!

Cheers,
Michael

farsidius said:

There are two sets of leads so buyers have options. The red lead is the JST connector which is what you'll use if you buy the JST connectors referenced in Jim's post above (also what I use). The white one is a Walkera connector and is commonly use in RC toys. Use the red one and ignore the white one, it's that easy.

Click to expand...

The two sets of leads serve two different purposes, the white one is for a balance charging each cell, the red JST connector is for connection to the device the battery is to power. Anytime there are two or more (2S, 3S, etc) its highly recommended to use a balance type charger as it will extend the life of the battery, and charge the battery correctly and safely.

Brent ,I like you, needed someone to explain all this to me, I didn't get any of it at first.

Every one is correct so, far but to simplify:

On the 1 cell 3.7 volt battery there are 2 leads for reason previously stated. White for hooking up to many RC planes/boats/cars that have a matching plug. The red JST is for charging and our use. It's only 1 cell, so no need for "balanced" charging.

On the 2 cell 7.4 volt battery. The JST connector is one we use and the other is for "balanced" charging. Because it has [2] 3.7 cells = 7.4 volts, those cells must be charged in a way that the both charge at same rate. You don't want 1 full before the other. It could overcharge and get fried before the 2nd cell is fully charged. Hence the term "balanced" charging.

The charger I show is a balanced charger....through some sort of "magic".LOL it trickle charges both cells at same rate so they finish at same time. If you overcharge a lipo they can catch fire, or explode. Notice they are in a plastic wrap rather than a hard case.

During overcharging and high rates of discharge, [seen in planes and cars when full throttled] the battery gets very hot, releases gas, and a slight swelling of the case is common/expected. It then dissipates and the covering shrinks back to original shape.

Single cells [the 3.7 one] don't normally have this issue. When done charging ...it's done. This charger shuts off when charge is finished on all sizes of batteries.

That's my caveman explanation. I'll leave the chemistry and details to others more versed in LiPo's

rharshberger said:

The two sets of leads serve two different purposes, the white one is for a balance charging each cell, the red JST connector is for connection to the device the battery is to power. Anytime there are two or more (2S, 3S, etc) its highly recommended to use a balance type charger as it will extend the life of the battery, and charge the battery correctly and safely.

Click to expand...

That's true for 2S and larger LiPo's, but not for this 1S. The 1S LiPo doesn't have balance charging. It's exactly how I explained it and this is corroborated with the product description. Red is JST and white is Walkara - there is no balance charge lead.

blackjack2564 said:

At a later date..... when ordering a new rocket unit, it comes matched to the old base. No need to ever change base, just the new units.

Missile works keeps a log/record of all sales & who bought them. When you buy a new unit, they match it to your existing base.

Got it? If not ask the question another way...maybe I'm not getting what you are asking.

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Just giving u a hard time Jim with all the corrections, not tying to passively say anything. Sorry bud. Should've put a smiley face. 😊

Really looking forward to the RTx

progress on my new 3D printed sled. I have to add some hard points to tie the antenna to and re-route the battery and switch wires to the proper location and relocate the battery box.

Got the E-mail! Purchase has been made. Great service from Jim as always. My first altimeter purchase was an rrc back in 99 and have always been pleased with the product and service. Really looking forward to this coming and using it.

Dennis

It seems like it should be -just- possible to mount the RTX/GPS && rrc3 side-by-side in a 54mm. Can anybody confirm, or have I misread the specs?

No not side by side.[I couldn't do it]
I put one on each side of sled with Lipo's in front. Easily done.

blackjack2564 said:

No not side by side.[I couldn't do it]
I put one on each side of sled with Lipo's in front. Easily done.

Click to expand...

Was it within a mm or so? Near miss, or not even close?

dhbarr said:

Was it within a mm or so? Near miss, or not even close?

Click to expand...

Butted up side by side...tight....will not go into center of fiberglass 54mm coupler, by 1/8in.overhang
That counts as not even close for me. Even if they did fit, being close to outside of coupler, terminal blocks stick up to high to clear.

Is there some reason over/under won't work for you?

A) idle curiosity and B) thinking about a triangular or diamond sled, since we can print whatever magic now.

Say, two sides for the MW RRC3/RTX (GPS up, TX down), one side for an Eggfinder TRS (TX up), batteries"inside", single allthread in the middle through the tip.

Basically if it it's worth doing it's worth overdoing. I'm sure there's 10 obvious things wrong w/it, just playing in my head.

Yes, having access to a printer will open many avenues of solutions a flat sled won't.

Let us know how you make out!

Will aluminum rods effect the transmission of the GPS?

cwbullet said:

Will aluminum rods effect the transmission of the GPS?

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It could. One could do a mockup bay and a ground test then take out the tracker and perform the test with the 900Mhz antenna in the free air over the same terrain. If the range is farther out in the free air as opposed to inside the ebay with the antenna wire parallel to the metal all thread, you'll have to decide if you can live with that range.
There's nothing more sickening than see a rocket disappear after launch and not see positions coming in after the expected apogee.

I haven't had trouble with a GPS getting a lock with the all-thread running parallel to the sides of the GPS receiver antenna ie. the square patch antenna. I haven't tried it with the the all-thread running over the top of the GPS receiver antenna and don't know whether that would affect the GPS reception from the satellites. It might.

I see Jim offers a mounting so the GPS antenna is facing "up" as opposed to the "side" like the Beelines, EggFinders and others. I think there's one rocket tracker that has a circularly polarized GPS receive antenna but the name escapes me for the moment.

A couple thoughts here. Facing up would mean getting the best exposure of the sky on ascent to get an apogee fix. Under G the GPS is going to cut out if it hits the speed limits and even if it doesn't, the doppler effect can cause dropouts on the GPS receiver. Some are better than others for resistance to doppler effects. Once the rocket is slower than 1200mph a good GPS will start sending again. With side facing still get adequate exposure towards the horizon and heck if the tracker bay is facing the right way, the antenna of the side mounted tracker "might" be facing up!:wink: Yeah right, we all know everything is flopping around up there.:eyeroll:

There are changes in rocket orientation going over the apogee and I will say the side mounting of the GPS receiving antenna hasn't hindered me or anyone I've witnessed with a viable recovery. The flopping around on descent under drogue, I've seen dropouts on
both the NMEA (like this device) and APRS trackers. Miss a couple on APRS and that's 15 seconds between position receptions. I've seen dropouts with the 1/sec NMEA trackers too but in both cases that could be due to Rf and tracker transmitting issues, antenna positioning (polarity) and receiving vagaries.

I've laid an AP510 SIRF IV tracker with a top mounted GPS receiver on it's side so the GPS receiver was looking horizontally on the ground and it locked on 6 to 9 satellites. Perfectly enough for a satisfactory recovery. If your MissileWorks top mounted GPS receiver antenna is lying on it's side on the ground in the rocket, you should be O.K. to affect a recovery. Geez, I've always wondered what would happen if one of my side mounted GPS receiver antennas ended up facing down. Admittedly not the best position but I don't think I've run into that situation.

Do not get fixated on the GPS altitude. It's nice to see a descending rate that is commensurate with your rockets status ie. your drogue is out and you should see an altitude descent that fits that state. Your main is out, you should see considerable slowing. If you see that, it's a big relief and you don't have to be able to "see" the rocket on descent. You know it will land nominally and you'll know where to go. Remember, the GPS is to find the rocket, you can always download that altitude flight info from your recording altimeters when you get the rocket back. You guys are going to like flying this way. I believe the Eggfinder TRS is one device that sends the baro altitude to it's receiver
along with the position instead of the GPS altitude. Perhaps the MissileWorks does the same too if using an RRC 3? Can Tele-Mega telemeter the baro altitude too?

Yeah, yeah. I know certain GPS recording trackers are necessary for record attempts in the nether portions of the ether where baro devices get a little "flaky" but I'm not going to get into a pissing fight here. Turns out some chipsets are better for this than others and better than the baro device when going to extremes.

One antenna solution is do an aft mounted bulkhead connector and get a short interconnect to whatever 900Mhz antenna you want to use. You ziptie the cable and antenna along your apogee shockcord and viola' the antenna is out in
the "free air" unencumbered by all-thread. You'd have to do something like an SMA or RP-SMA socket on your transmitter module and have an interconnect to the inside wall of the bulkhead. Ebay is a good source for cables.

One other tidbit: I have a tendency to set the main deployment for high fliers to 800' and above. It will give you time to get some good position fixes if the rocket begins to drift out of the radio foot print. If the rocket is at the limit of it's range, your last packet may be up high and you blow the main down low and you lose packets because the rocket is out of range. If you blow your main a bit higher, you'll be able to see a drifting trend develop on a mapping receiver and know how to proceed once you get to the last known position. This protocol could be helpful if flying at the limits of the radio range. If your flight is going to be landing pretty close, not so important.
If a live mapping device is possible/available, tracking gets really cool. Have fun! Kurt

I finally had the opportunity to play with my new RTx yesterday. This is my first experience with tracking of any kind. I had 3 flights with it, none of which went anywhere close to going out of sight or off of the field. I was interfacing with the Missile Works LCD module.

My first impression? Outstanding! It was as close to "ready-to-fly" as you can get. Everything is very intuitive. If you have never used tracking and have been considering the RTx, I would recommend that you just go right ahead and do it. You would not regret it!

As CJ mentioned above, a 1S LiPo really won't drive the receiver and LCD module. You need a 2S. I initially tried the 1S and even at maximum contrast, I could just barely read the LCD. The transmitter is fine at 3.7V.

I'm really looking forward to giving it more of a challenge at Freedom Launch in a few weeks. I will update this post with my experiences...

Cheers,
Michael

blackjack2564 said:

Here is a list of all the things used during testing & final use, everything I ordered came from USA shipping address & was Ok'd by Missileworks.





Battery I use on base.7.4 volt No room inside, I just tape to exterior, it very large. The LCD and base use more juice.

https://www.hobbyking.com/hobbyking/store/__26564__Turnigy_1500mAh_2S_25C_Lipoly_Battery.html

Click to expand...

Quick start guide says: Recommended is a 1-cell 750mAH Lipo [Turnigy Nano-tech @ HobbyKing]. Is the suggested battery for the Tx or Base? Micheal in post 262 says to go with a 2s in the base. Can someone suggest a 7.4V that DOES fit in the base?

bill2654 said:

Quick start guide says: Recommended is a 1-cell 750mAH Lipo [Turnigy Nano-tech @ HobbyKing]. Is the suggested battery for the Tx or Base? Micheal in post 262 says to go with a 2s in the base. Can someone suggest a 7.4V that DOES fit in the base?

Click to expand...

I talked to Jim about a 2S lipo and he said no problem. I am using a 2S 460 mA in the TX and a 2S 300 mA in the RX.

460mah Lipo

300mah Lipo

Thanks Tim, just ordered 2.

Interesting that everyone seems to be using 2s lipos with their RTx hardware. During beta testing, we used the following batteries:

Rocket RTx - sparkfun 1s 850 mAh
Base RTx - sparkfun 1s 1000 mAh

We never had a problem with these batteries and they lasted for multiple flights and launch days without charging.

ben said:

Interesting that everyone seems to be using 2s lipos with their RTx hardware. During beta testing, we used the following batteries:

Rocket RTx - sparkfun 1s 850 mAh
Base RTx - sparkfun 1s 1000 mAh

We never had a problem with these batteries and they lasted for multiple flights and launch days without charging.

Click to expand...

I only used 2S because that's what I had in my possesion & since Jim said it was ok, I used them!

What I noticed when I used a 1S lipo for the base and LCD screen, the LCD screen was barely visible even on maximum contrast. With the 2s lipo, this is not an issue. It does not fit in the handheld case, but I will just strap it to the back.

Crazyrocket said:

What I noticed when I used a 1S lipo for the base and LCD screen, the LCD screen was barely visible even on maximum contrast. With the 2s lipo, this is not an issue. It does not fit in the handheld case, but I will just strap it to the back.

Click to expand...

Same situation here. 3.7V drives the RTx just fine, but the LCD is illegible in a normally lit room at maximum contrast. It would definitely not be enough in bright sunlight. 7.4V was the answer for me. Jim confirmed for me as well that the 300 mAh nano-tech listed above will fit in the case. I plan to get a couple with my next Hobby King order. Until then, it's not an issue for me to have the battery outside of the case. YMMV

Cheers,
Michael

Interesting as we haven't had a problem with viewing the base LCD panel using the batteries mentioned above.

Maybe Jim can comment as to why you had to use a 2s with your base.

Ben