critterhunter

One more picture...

By the way, the board is smaller than what it looks like while being held in my hand in the photos. Look at the ruler next to it above.

Haven't dove too far into it yet with a volt meter but want to check a few things. Wonder if the OUT DC jack on the thing is passing straight battery power or is being run through a voltage regulator to keep the output steady?

Also, as has been discussed earlier in this thread there is a voltage regulator on the bottom of the board. Still haven't checked the output voltage of that. Wonder also how much power it can handle to run a camera directly off of. Could be risky if the thing gets hot. Even without running something else off it I'd keep an eye on it and see how hot it gets. An extra heat sink may be in order or keep good airflow to it on the plane.

I'm going to assume the TX can be powered directly off a 3 cell lipo since it appears it accepts 9 to 12VDC, and shouldn't drift it's signal as the lipo discharges down to 9V since it features no tuning knob and a lock on channel. Also, the regulator in the TX should keep the voltage level constant to all aspects of the unit?

Would also like to hitch a amp meter up to this thing and see exactly how many amps it's drawing. Don't want to over tax my lipo with the motor at WOT and this thing transmitting.

daubut

Nice to see the photos of the TX in hack stage 1. I ordered mine yesterday so when it arrives I will start by removing the case and board and start to shave some weight off mine also. I will probably just solder the cable for my cameras AV out directly to the board removing the connectors. I will post some pics when I get the mods done.

I was also thinking that getting the weight down as much as possible would help me be able to install it in a more permanent position closer to the tail of the plane. Trying to get the TX as far away as possible from the RC RX hoping to eliminate interference issues before they arise. I am trying to keep my weight down and trying to keep most additions as close to the CG as possible. I want to try to keep the overall weight of the plane below 6-7lbs. I ordered a larger prop went from a 10X5 to an 11X4 to get a little extra pulling power. With 1.2 hp rating on the OS .46 it should pull the plane nice and docile (I hope).

Do you plane to leave the plastic casing off the TX antenna? If so, do you plane to install the antenna in the foam or have it stick out? I have been looking into the foam planes and some of the homebuilt foamies lately and am intrigued. Did you build your own hot wire foam cutter? I saw a few posts about it and have seen some homemade plans for a few, seem simple enough to make one.

Great info thanks, and good luck this hunting season!

critterhunter

Yea, after having this TX sit around collecting dust for a good year it's nice to be toying with it. When I bought mine I think it was like $50 or $60 and that was (and still is) a great price for a 2.4ghz 2 watt system. Now that it's thirty some dollars how can you go wrong?

Don't know if I'll remove the RCA and power jacks yet or not. I would like to take off that plastic elbow and nut though because they serve no useful purpose without the TX case. If anybody figured out how to remove them without desoldering the antenna let me know. I expect you could heat up an exacto knife and slit the plastic eblow down it's side. As for the nut you could dremel it off or something.

The AP foam plane I'm building should be able to lift this thing with no problem on a tiny CMOS or CCD camera and probably even with my Aiptek 5100M (4 ounces) pocket camcorder if I want to plug that into it. The foamie AP ship I'm building currently has a 48" wing and wing loading at the moment looks like it will fall between glider and trainer loads. However, if the weight gets a bit higher than I want I'll just hot wire out an even bigger wing to slap on it to get the wing loading about where I want it.

Good idea to move it as far away as possible from the RX antenna. On the other hand, using a good full range interference blocking RX such as a JR Sport should probably eliminate any concerns. I'd play it safe and do a VERY far away range test with a buddy watching the plane so you can be sure the RX still has control. Drive a block or so away and play with the TX as he watches what the plane is doing on the ground. As an added precaution I'd give the plane some right turn in the trims before launch. That way if the thing does loose contact it will start doing lazy circles until you can get close enough to regain control. The motor should automaticly shut down on most ESCs if it looses the signal so that won't be a concern.

As far as the antenna goes I'm going to leave the plastic sleeve off. Like I said, the antenna wire is real flexible and shouldn't break or loose it's shape even if you cranked it from end to end in a loop. When I mount it on the plane I'm probably going to stick it straight up and down inside the foam and sticking out the top of the fuse. I'm not too worried about protecting it, just keeping it in one position in a way that it won't flop around on me. If I decide to mount the TX on top of the wing the antenna will either point straight up or be horizontal trailing towards the tail. Some people report better reception on other transmitters by having the antenna sideways, others straight up. The main thing is to position your camera RX in the same way on the ground. I'd also mount the RX on top of a four or five foot PVC pipe you stick in the ground just to give it the best chance of not seeing interference. Probably not a big concern with this powerful of a unit.

Yep, made myself a homemade hot wire bow and a hot wire table bandsaw style cutter. Both are VERY simple to make and cost just about nothing if you have the parts laying around in the garage. You can go to the thread called "Here's A Simple A FREE Foam Build Plan! Cool Looking Plane Too..." in the foamie forum and read that. WARNING: I'm very long winded in my messages on there but others helped me walk through building a foam cutter, wing jig, and that plane. All the info you need is there. Later on, towards the end of the thread, you can see my final third build version of that plane complete with photos and step by step build instructions. While I'm not using that plane for my AP I think it would be the perfect platform for it. Just scale it up in size to whatever you want wing wise. Dual booms, single aileron, and an elevator type setup. My current AP foamie build is in the other thread in this AP forum under "Homemade Foamie AP Platform" or something like that.

Once you get into hot wire cutting foam bodies it will become an obsession. You learn so much more about planes, how they fly, and some rather good build skills as well. Saves you a ton of money and also gives you added satisfaction when you fly something you built from scratch.

dzbum

My Feedback: (5)

I am still waiting to see someone do a range test on this tx more than just a quick walkabout. I doubt it is a 2w tx but it could be enough to work well. Daubut did you receive the one you orders yet ? I would be interested to see what you think. Like you said for the price if it is only good for none RC stuff then nothing much lost.

daubut

I haven't recieved mine yet. I haven't gotten an email from the seller saying he shipped it yet. I will post as soon as I get it. Plan to do same range/antenna testing as soon as Iget though.

critterhunter

Based on a few other transmitters I've peaked at the internals on I'm willing to bet this thing is 2 watt or at least very close to it. Either way, I'm sure it's more than powerful enough to handle any kind of distance you want to fly at, even at some further fly-by-wire flights that are out of visual sight. However, a good way to get a general idea to it's output would be to hitch an amp meter up to it and see just how much current it's drawing. I would figure there is some type of formula to figure if it's at least close to the power output it claims. I'd also like to do an amp meter reading on it anyway just to judge how much load it's putting on my plane battery. Might be a good idea if your lipo is barely able to handle the amp draw of your motor at WOT.

trireme

Based on the current consumption rated at 12v 500ma, it is likely that this unit is more around 200mw, not 2000mw. 200mw with good clear line of sight, should go 1000ft. Most 2 to 3 watt broadcasters draw more power then that.

critterhunter

Hmmmm.....Now I'm going to have to test mine for myself to see. A TX this large that gets this hot (heat sink the voltage regulator on the bottom!) shouldn't be just 200mw. I know my 800mw unit isn't 1/5th the size of this thing. Yet, the proof is in the numbers and not just superficial observations. I'll check a few things and post some info...

trireme

http://www.ayagroup.com/product_info...oducts_id=1450

Looks kinda like this? But this says 0.1w rf power...

dzbum

My Feedback: (5)

It would be nice to think this was a 2w TX but I agree that it is too good to be true. Given that it draws 500mA @ 12v I think 100mW-200mW range is probably more likely.
Has anyone had experience with cheap 1.5w TX's from China that they sell on Ebay.
[link=http://cgi.ebay.com/3000mW-Wireless-Security-video-AV-Transmitter-Receiver_W0QQitemZ300055423990QQihZ020QQcategoryZ4 8632QQcmdZViewItem?hash=item300055423990]Ebay Tx link[/link]

I think this is probably a true 1.5w but I would like to hear from someone who has seen one in use or tested one.

critterhunter

I know Randall had the 1.5w unit and he said this 2w unit was the same thing as far as he could tell as the internals looks very similar. Either way, I'll report back when I have something to add.

critterhunter

Did some more weight savings measurements on the TX. I used a dremel to remove the metal nut and plastic elbow sleeve at the base of the antenna. The main sleeve just pulls right off but you have to slit the elbow and nut to get them off. There is plenty of room in there to not hit the antenna or it's little board near it's base so just take a little care with a cutting disc on a dremel or something. Without the elbow/nut the TX now weighs 2.6 ounces (75 grams). That compares to 2.8 ounces (78 grams) for the TX without those components removed, and 2.9 ounces with the main antenna sleeve still on as well.

There is still plenty of weight savings to be had. For instance, on top of the video jacks there is extra white plastic (can be seen probably in the above pictures) that has empty mounting screw holes in it. You can heat a knife or dremel that off as well, which I plan to do. At least two or three of the board's corners have way extra wasted space on them where the main ground trace (very wide) is. If you cut off those corners without cutting through the entire trace you should save some more weight. There are various other things that could be hacked off the board to get the weight lower, probably under 2 ounces...Such as removing the video/audio jacks and wiring the camera directly to the board or using a servo plug to hitch the camera up to it. The DC in/out jacks could also be removed and wired directly to the board or by using a mini plug such as a servo harness. Not sure if I'm going to do those things as the weight is pretty good as it is.

My next step is to check the amp consumption of the board. My main concern if anybody knows is how much current standard servo plug wires can handle? I've already got a servo plug wired directly to my plane's battery leads that I plan to run my Aiptek 5100M pocket camcorder off of, and perhaps this TX with a CCD camera when the camcorder isn't installed.

Again, I'd probably add an extra heat sink to the voltage regulator and/or the other component on the bottom of the board if they seem to get hot while test bedding.

As for the anenna, I'm planning to glue it directly to the side of the TX board to keep it in one place. At the moment I'm thinking the antenna will be pointing straight down toward the ground but am not sure which orientation is best for a strong signal. Which way do people normal point the TX antenna and what's the proper position for the ground antenna?

dzbum

My Feedback: (5)

It looks like standard servo cable is AWG 24. The chart I am looking at says 3.5A for chassis wiring and 0.6A for power transmission. Hope that helps.

questtek

As for the anenna, I'm planning to glue it directly to the side of the TX board to keep it in one place. At the moment I'm thinking the antenna will be pointing straight down toward the ground but am not sure which orientation is best for a strong signal. Which way do people normal point the TX antenna and what's the proper position for the ground antenna? Point the transmitter antenna down and the receive antenna up. This privides the same polarization on the antennas which is very important. The worst possible arrangement is one antenna horizontal and the second vertical.

dzbum

My Feedback: (5)

Generally it makes no difference if it is horizontally polarized or Vertically polarized as long as the RX and TX are the same. The most common is vertically polarized I would say.

critterhunter

I did a bit more playing with the weight on the TX tonight. Heated up an exacto knife and cut off the extra white plastic above the video/audio jacks where there are dummy screw holes. I then fired up the dremel with a cuttting disc head and went to work on the edges of the circuit board where there is extra unneeded board. I can post a picture of this if anybody wants it but mainly you just nip off any extra board at the edges without crossing any trace lines or shorting the main ground line which is rather thick at 2 or 3 corners. Also found at one near corner a dummy capacitor lead hole that wasn't being used for anything and took a good portion of that out. As said, feel free to dremel off any extra board edges but don't cut through the main (fat) ground copper trace circuit or any other traces. In other words, cut as far into the board as you can without crossing over or cutting in half any trace lines. With the white plastic at the top of the video/audio input jacks removed and the board being trimmed I save well over 2 grams or so by my scale. The white plastic could also be trimmed down even more as it has a large body enclosure that goes well behind the av jack leads, short of just removing them and soldering the camera directly to the board or using smaller plugs. The DC in/out black plastic jack enclosures could also be trimmed up a bit. When trimming the board you'll see what looks like a transistor laying on it's side near the edge of the board that also has a lot of dead circuit board space under it. If you lift it you can trim a good bit of board off under there as well. Again, just do NOT cross any trace lines or cut any in half. Plenty of room to hack off uneeded board if you know what you are looking for.

dzbum

My Feedback: (5)

Did you fire this unit up before you hacked it and do a ground range check?

qtip67t

How do I get off this thread?

critterhunter

No reason to. If it doesn't provide good range I'm not planning on selling it anyway. I'm mainly stripping it down here and there for something to do in between work on my AP plane that is mainly going to carry an Aiptek 5100M pocket camcorder. In no big rush to get this TX into the air with a CCD camera, but later I will.

I doubt it doesn't get good range based on some of these remarks. Quote from Randall (He was using the same ebay cheapie but the 1.5 watt version)...

"I have their 1.5 watt version and if you take it out of the case and substitute servo leads for the rca plugs it's very light. My setup will give video as far as I dare to fly. Especially with the GP Patch antenna I made for for my receiver. "

And another...

"Those antennas actually work VERY well. That little circuit at the bottom of the antenna is a base load. Mine does really well with the stock antennas. I sent photos to Bill Strong a while back asking if I could use better antennas and he told me that the ones that came with it were high gain. They look funky but they work a long long ways out. "

And, if you dig back in this thread you'll see some ground range tests of the unit with good results.

But, was a little too drunk last night working in bad lighting and cut a little too far at two points on the board's ground trace. Had to add a couple tiny wires to the board to fix that. Nipped the transistor trace near the bottom of the board and am not sure if I might have shorted it to ground. If you look in the picture you'll see the arrows pointing to what I'm talking about. I'm getting a ground signal from the bottom pin and the next one up. Anybody know if you are supposed to?

Don't drink and dremel!

critterhunter

Finally picked up some DC power jacks to match the in/out on the TX and RX. Tonight, after I check the above part out to see what I might have done to it, I'm going to fire the unit up and do some ground range tests. Will post the results when done. I also want to check the heat of the voltage regulator/transistor and a few other components to see if things are getting too toasty on 12V. If they are I'm going to add a heat sink to them. Radio Shack sells heat sink past and aluminum heat sinks that work well for this. The paste doesn't glue the parts together so you'd need to epoxy or attach the heat sink in some fashion. Also plan to do some voltage readings on the board to figure out what the regulator is up to and also check the DC output jack on the TX to see if it's passing straight battery voltage or running it through the regulator. Probably do an amp reading to see just how much current the board is drawing as well.

All this is if I didn't destroy the board in my drunken dremel work...

critterhunter

Alright, fired up the unit and here's some stuff I found out. First, I had the RX plugged into a VCR to record a ground range test. My house is aluminum and didn't have high hopes for a ground test since I live in the suburbs. However, The road by my house climbs up a hill a good clip so I figured that would help. Loaded the TX into my truck and took a drive up to the top of the road, about 5 tenths of a mile by my truck's dash. Got home and checked the VHS tape out. Despite passing through the aluminum siding and being inside my truck, not to mention the numerous ground clutter and houses in the area, the unit did keep a stabile video. Well, there were a few drop outs but at the furthest distance (top of the hill) the video was fine again. So, I would figure it's going to do well in the air.

I checked the output voltage on the DC out jack while the unit was plugged into a 12V power source. I would have figured it was just passing straight battery voltage to the out jack but to my surprise it's dropping the voltage down to 8V. It doesn't really matter since I'm planning to run a 12V CCD camera off the plane's 3 cell lipo directly as well and not routed through the video TX. I don't want to over heat the TX because one or two of the parts on the bottom of the board get pretty toasty.

I decided to heat shrink the antenna to protect it and avoid shorting/etc, and also heat shrinked the TX with clear heat shrink to protect it from an accidental short as well. The antenna has been mounted under the clear heat shrink on top of the RF shielding box. I also cut away the heat shrinking around the voltage regulator and transistor so they can get air. Might still add an extra heat sink to those but am going to check the temps with a laser temp gauge first to see just how hot they get. Right now my plans are to mount the unit with the antenna horizontal and inside the foam body of the plane. You can also see I used a servo plug and DC jack to plug the unit into the plane's 3 cell lipo power. The unit now weights 2.8 ounces including heat shrink and DC/servo plug.

I'll get around to doing some amp readings on it next and post the results.

dzbum

My Feedback: (5)

Sounds good. .5 mile with the RX inside is great. Did you put an Amp meter on it to see how much current it draws yet ? I would be interested to see how much it pulls.

critterhunter

Not yet, maybe tonight. Will post results. I can tell you this, though...I have it plugged into a servo plug with standard servo wire feeding directly off the plane's 3 cell lipo and I was checking the servo wire for heat. It stayed cool, so I at least know the servo wire isn't going to cook. It's got to be below an amp, probably at the 500ma they claim for the unit. Will check.

critterhunter

Got my CCD camera today. Very fast delivery since I ordered like Thursday or Friday. For $29 how can you go wrong? The video I saw done with this camera looks great. It's way smaller than I thought and weighs next to nothing. I was always under the impression that CCD cameras were much larger than CMOS types, of which I have one of those on a 800mw 1.2ghz wireless setup. Only used that a couple times and that's been the extent of my aerial video experience thus far.

Can't wait to rig this CCD up to my 2 watt 2.4ghz tx. The power/video/audio cable it came with has a little plug on the other end to mate them to the CCD board. On further inspection I see there is no ground trace to the board for the audio/video inputs. Guess that answers my question if audio/video cables have a ground trace connection in the shielding or something.

Going to cut this tiny plug and it's thin wire off the cable to plug into the camera as is. I have the same plugs laying around so I'll solder the other end to the same style plug, then put an outlet on the 2.4ghz TX's board so I don't need any RCA plugs on that end. Might end up soldering off the RCA jacks on the TX and save that weight since I won't need them.

dzbum

My Feedback: (5)

Which camera did you decide to go with ?