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Help Me Understand My TRS

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Kruegon

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Long, short, complicated and simple.

Purchased an Eggtimer TRS of the yard sale. I'm finally getting ready to use it. I'm an Eggtimer noob. Scratch that. A noob knows more than I do.

I've extricated the board from the nose cone it came in. I've purchase a Black Aero receiver case. I've ordered the terminal blocks from Eggtimer. Now I need to order the Lipos and charger.

Here's where I need some explanation.

Do I use 2S 7.4v Lipos on both the altimeter and the receiver?

The receiver has an orange wire coming out of the top of the main board. What's this for?

The main board has a button in the bottom left. The case has a button on the right side. Are these the same purpose? Do I need to de-solder the on-board button and wire the case button here?

Where do I wire the on/off toggle switch to on the board?

Yes, I'm sure I look like an idiot right now. Don't care. It my first time playing with Eggtimer products. I'm feeling very stupid right now. I just want to get it working.

ImageUploadedByRocketry Forum1486518981.830096.jpg
 

ksaves2

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That might be the wiring for the backlight in the LCD display or it's the wires to go to the momentary push button you need to be able to command the device. That's the black button on the side of the case.

Go to the EggTimer site and download the build photos in sequence, the instructions and the user guide. Open two windows on your computer/device and scan/read the instructions while looking at the build photos.

Yeah, you didn't build it but this should orientate you to the connections and such. Now read the user guide. It will tell you everything you need to know.

You need a 7.4V lipo for both the LCD and the tracker. The biggest I've been able to fit in the handle of that LCD case is 1500Mah. Do a search here and you should be able to find photos here. The fit in that case is tight.

http://www.rocketryforum.com/showth...finder-LCD-Build-Thread&p=1626820#post1626820

Kurt
 

Kruegon

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Thanks. I need to get this figured out. I've got some serious plans for this one and another upcoming Eggfinder.
 

Kruegon

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I can't find anything pointing out what the orange wire is for. Anybody got a clue?
 

tfish

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Is it a single orange wire or two? Do they go to pads labeled BL ?

Tony
 

Kruegon

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Two and yes to BL. But the other end goes no where.
 

Kruegon

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Ok. This is way more confusing that it feels like it ought to be. So on the black Aero case, you have a rocker switch and a button. When using Liops, you wire the rocker switch inline between the battery and board. Where does the button go?
 

ksaves2

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Ok. This is way more confusing that it feels like it ought to be. So on the black Aero case, you have a rocker switch and a button. When using Liops, you wire the rocker switch inline between the battery and board. Where does the button go?
Looking at your board you will have to desolder that tactile switch next to the buzzer in the lower left. You connect the momentary swtich to that connection.
If you don't want to do it, you could get the right battery and negotiate with Connor if he would do it. You would need to get a Lipo that fits in the handle.

Kurt
 

cerving

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Ok. This is way more confusing that it feels like it ought to be. So on the black Aero case, you have a rocker switch and a button. When using Liops, you wire the rocker switch inline between the battery and board. Where does the button go?
It goes to the two pads marked "SW" above the little horizontal button on the PC board. Those pads bring that button outside the board, which is something you'll need if you're using a TRS. The very early LCD boards didn't have those pads... I added them when the TRS came out.
 

Kruegon

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Ok that's what I was missing. So if I want to use the back light, I'd need another button or switch.

I believe my soldering skills are good enough for the battery leads and wiring in the button. It's more the tiny legs on the main chip that I worry about.
 

timbucktoo

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You really dont need the back light unless you are launching at night. I did not connect the light to mine.
 

BDB

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The black case in your photo is the battery case if you want to use AA batteries. You will need to disconnect it and attach a JST connector to the leads if you want to use the Black Aero case and a lipo like the one mentioned in the previous post.
 

Kruegon

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This is the battery I use for the LCD Reciever. It also fits perfectly in the handle of the Black Aero case.

https://hobbyking.com/en_us/turnigy-nano-tech-1500mah-2s1p-20-40c-lipo-receiver-pack.html
Thank you. I've been looking at lipo batteries a lot lately. I still do t fully understand them yet, but I'm getting there. So many different connectors and so many charger options.

The black case in your photo is the battery case if you want to use AA batteries. You will need to disconnect it and attach a JST connector to the leads if you want to use the Black Aero case and a lipo like the one mentioned in the previous post.
Yes. I already have a Black Aero case. Older one in blue. The battery box pictured was only surface mounted so it should be an easy removal. Clean the surface and holes. Tin the jst connector and solder through the board. Though I am considering putting a terminal block in for a more modular aspect. I'll decide later about the backlight. I can always as a button or switch later if I find I need it.
 

Kruegon

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It appears that if I want to optimize the TRS, I need 3 lipo batteries. Two for the TRS, one for the LCD. I realize I can technically run it off one battery, but it put a larger drain on it.
 

BDB

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You are right about 3 batteries, but you can run the ejection charges on a 9V battery if you want.
 
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Kruegon

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No more than they cost at hobby king, no reason not to pick up 3. I mean once you have the charger, the batteries are easy.
 

sl98

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ImageUploadedByRocketry Forum1486604235.562092.jpgImageUploadedByRocketry Forum1486604303.054329.jpg

I use 2 of these Wild Scorpion 500mAh LiPo's on my TRS. Got them on eBay. They work great. I also use them with my Quantum but I run the Quantum with a single battery.

You can find them in a 2 pack for under $12 and free shipping.
 
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ksaves2

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You are right about 3 batteries, but you can run the ejection charges on a 9V battery, if you want.
No not necessary. In a minimum diameter rocket I feed the pyro channel and the TRS off of one 1300 mah 7.4V 2S battery. I use a Featherweight screw swtich to turn off/on the pyro side.
To Jeff Jones: Thanks for posting that link. That's the battery I use and I couldn't find my old thread that showed it. That is the largest capacity that fits in the handle. On that link I placed in #2 the bent over pin socket at the top of the picture goes to the metal locking toggle switch seen on the right for the back light. I had some friends in a computer business that let me salvage wires and plugs out of old computers.
Folks are right if one is not launching at night, the backlight isn't needed.

People, with dual battery situations one MUST have a switch on the battery to power the electronics AND one on the battery for the pyro circuit. Why? Because if one pre-prepares a rocket for flight a week or two in advance, if there
"ISN'T" a switch on the pyro battery, it could be drained EVEN though the battery on the electronics side is turned off!

This is not just for the TRS, I've observed this with several dual battery altimeters I've tested. How do I know? Just put LEDs with the proper polarity on the ematch circuits, connect up a battery on the pyro side with no battery on the electronics side to power up the flight computer. One will see a faint glow coming off of the LED's. That is current going through the continuity test circuits. It won't blow the matches but it will slowly drain a battery connected to it that doesn't have a switch in the off position.

If one isn't aware of this "little" detail then they will be in for a little surprise when they get to the pad and their device starts beeping a fault when the pyro battery is dead or with insufficient current. Worse yet would be
if there was just enough current left not to trigger a default situation and one or none of the deployment ematches fire during the flight.

Sure, if one plugs in fresh batteries on site and flies, not a problem with an unswitched pyro battery.

This leads to the situation where one has to make accommodation for two switches in a small rocket. Might be hard to do and one could consider a deployment device that is meant to be used with one battery in that situation or
do as I did with the TRS and wired one battery in parallel with a screw switch on the pyro circuit that I can access through the static port. I plug the single battery to power the entire system with the screw switch off on the pyro side and activate the TRS and get it in standby mode. I have no room to switch the battery. The act of plugging the battery in powers the electronic side.

I ground tested with ematches with NO SWITCH on the pyro side and plugged the battery in and out and tried to see if I could get the matches to fire spuriously and nothing happened. I used the Featherweight switch not as a "safety" feature as some say it would be but as a means to cut the current drain. Plus I could say it is a "safety feature" that would provide psychological assurance to any RSO.

Nonetheless, if you want to fly the TRS with a single battery use a large capacity one and you won't have to worry about it.

Again, this is not just something to be aware of with a TRS. Any dual battery installation can exhibit this behavior. The early EggTimers that are dual battery do it too. It's a characteristic one needs to be aware of because if
they don't take it into account it could inconvenience them or worse off, they push the button without heeding a devices warnings.

Yeah, there are double pole single through keyswitches out there but the ones I found are big and heavy. Kurt
 

cerving

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Or better yet, hook up the battery on your work table before you take it to the RSO. You're probably going to top off your LiPo's the night before, anyway. Not connected, no drain.
 

ksaves2

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Or better yet, hook up the battery on your work table before you take it to the RSO. You're probably going to top off your LiPo's the night before, anyway. Not connected, no drain.
Yeah, that's what I do Cris. Had an intense discussion about switches in another thread. A TRS behaves safely with one battery and no switches. Plug in, make sure it's in standby mode and go to the RSO. I did the pyro switch so if I'm questioned
by an unenlightened person I can rightly say "it's really safe" since there is no power "on the pyro side".

Let's say that a device (not necessarily any of your products) suffers a crash and is destined to blow the ematches the next time power is applied no matter what. Well, would one want that to happen while the rocket is on the pad pointing up with one or more of the deployment charges going off? If it's a big rocket, besides getting blasted in the face, the upper pieces could come down on one's head.

If one was in the prep area with the rocket lying on the ground pointing away from any and everybody and given the fact the flier has face protection which is safer? The rocket landing on your head or the one that blows horizontally on the ground and is restrained by the harness(es) while the preparer or flier is off to the side?

Once the battery is plugged into the TRS, pyro switch or no pyro switch, if the charge remains intact and the TRS is "quiet" in the standby mode, it is perfectly safe and "not" dangerous.

I think the same can be said about your Quantum too. Kurt
 

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