RC India

Recently I had a lot of problem carrying my FPV screen around with the hood and receiver post on it, so decided to try and integrate the 5.8GHz rx into the screen itself.
The screen and fpv system are from www.quadkopters.com (http://) (http://)

I first opened the RX and removed the casing. I found that the board itself is not that big or bulky, it contains only a few components other than the 5.8G module. Next I opened the Screen and found the correct spot for fixing the board.

Using a multimeter I found the correct pads to solder wires between the screen circuit and the RX, soldered all the wires, applied some industrial isulator tape and fit the rx circuit directly to the screen.

(https://lh4.googleusercontent.com/-Or1Zi3gzc98/U397HF24rEI/AAAAAAAAAlk/7wpO8kjXSXc/w1064-h709-no/IMG_8338.JPG)

(https://lh4.googleusercontent.com/-JQTp6c5Olzw/U3-FG44GeFI/AAAAAAAAAmw/Zw7G4wiYCq8/w862-h709-no/Rx+wiring.png)

(https://lh5.googleusercontent.com/-FMD68a6586w/U397D3w6skI/AAAAAAAAAlc/CQRw02AUk3A/w1064-h709-no/IMG_8340.JPG)

(https://lh4.googleusercontent.com/-jKn_PSXvWx0/U39_DJl8RYI/AAAAAAAAAl8/Oe7iYjPEdXA/w1064-h709-no/IMG_8341.JPG)

More pics

(https://lh5.googleusercontent.com/-ZeJs9Fw8L0k/U39-J-6iKLI/AAAAAAAAAlw/ij98lAbNg4M/w1064-h709-no/IMG_8342.JPG)

(https://lh3.googleusercontent.com/-RDNu1Cn9yCc/U3-EXojuo5I/AAAAAAAAAmc/aVrL1d8PW0I/w1151-h709-no/Vido+rx+screen+wiring.png)

(https://lh3.googleusercontent.com/-2ViOvaBkF6M/U3-CT7TAZ5I/AAAAAAAAAmM/2CgE_NAiy-Q/w1064-h709-no/IMG_8346.JPG)

(https://lh3.googleusercontent.com/-KuBF2mSpsiU/U39_L_laUKI/AAAAAAAAAmE/GfKtnzotouk/w1064-h709-no/IMG_8343.JPG)

(https://lh6.googleusercontent.com/-Ls7HuWvsOog/U3-Cv9yvweI/AAAAAAAAAmU/At5qz8FnvzU/w1064-h709-no/IMG_8347.JPG)

Clever, I have the exact same screen and I believe that is Boscam 5.8 Rx, Gonna give it a shot.

Very very Clean build. I am not a fan of velcro either, had to stick my Rx behind the screen and run those bulky wires around.

The Rx gets pretty hot on 3s. The Rx case acts as a heatsink, but since you removed it, drill some vent holes on the LCD cover.

This thought came to my mind as well. You seriously need to make some holes in the back panel of the screen. Otherwise it might damage your screen or damage itself.

you guys are ri8, the Rx is getting hot on 3S battery.
First I thought let me use some kind of Voltage regulator circuit.
But it will be a lot of extra work for just a simple issue.

But then Volla!  Here is the easy fix.

USE BALANCE CHARGING PORT TO POWER THE Rx.

I ordered 3S 4-Pin female connector. And will connected as shown below.
(http://i1144.photobucket.com/albums/o483/chilschils41/FPVScreenMod_zps02773738.png) (http://s1144.photobucket.com/user/chilschils41/media/FPVScreenMod_zps02773738.png.html)

won't that be unbalancing your Lipo badly with every use?

You will need a special balanced individual cell charger every time to revive the LIPO That's if you don't end up over discharging your LIPO on your RX and Screen.

Worst thing about using lipo for RX and GS is that if don't watch it, it will invariably over discharge your LIPO below nominal 3.0 per cell that too at less than 1C rate of discharge and that's clear discharge. The cells won't even get back the min 3 Volts even after removing from the load thereby suffering irreversible permanent damage with every use. 

The LIPOs used for GS and Tx/ Rx tends to get bad fast.

There are holes behind and I have made some more, both the rx and the screen are connected in parallel using one battery. If its very hot then I may install a small cooling fan as well.

There is an insulation backing between the screen and the rx to prevent heat to damage the screen

Prateek can you put up a pic with the screen working. Just wanted to see the quality of display.
A lipo alarm for the GS batteries would be a good idea then, integrating it on the screen would be better(probably on the back I guess or somewhere on the sides so that it can be monitored while in use).

@Sidewinder- Sure, I'll send in the evening(My new GoPro is coming! Really excited  ;D)
I'll need to buy another alarm but, I'll need to rewire it to fit it inside the panel.

Use of Lipo voltage alarm is a good idea.

The Screen Back Cover ve already got holes, so U can install a small fan. Next thing is open the setup and U ll find some Regulator ICs U can easily identify them as most of the regulator ICs are of three Pins. These Ics are the main cause of Heating. Get some Heat Sink Paste from the market and apply onto those Ics. This will not completely eliminate the problem but ll reduce the heat to a good extent. Then also put a fan @ the back of the Panel. This Heat Sink Paste is also used between the heat sink fan & Processor in a computer. Try it n also do some clean soldering coz since the system is portable the wire U solded may get removed. coz rough soldering is not so rigid, n if any wire gets removed n touches any other track or solder spot of the board then U may loose the entire setup itself. Put some flux paste before soldering n try to sold the wire as near to the insulator, this will provide rigidity, n in case of movement the wires will not get removed easily.

(http://)how about introducing a simple 12v to 8v circuit with only 3 components to power the Rx.

here is the link to circuit diagram
(http://2.bp.blogspot.com/-HQRbuZXGmqg/TpNKeqd-uiI/AAAAAAAAAkE/l-TLPeoDj90/s400/12V%2Bto%2B8V%2BDC%2Bconverter%2Busing%2B7808%2Bregulator%2BIC.JPG)

http://schematic-audio.blogspot.com/2011/10/dc-converter-using-7808-regulator-ic.html (http://schematic-audio.blogspot.com/2011/10/dc-converter-using-7808-regulator-ic.html)


and since the Rx only runs on about 150mA, the IC should not turn too hot I believe.
Or just screw a piece of metal as a heat sink and it should work.

Also about Discharging battery cells below 3.7v is highly unlikely because, the 7" TFT and Rx both runs
on minimal current ~150mA to ~200mA. so say if you have 1000mAh 3S powering both Rx and the Screen,
should last you 3 hours roughly if you go with ~300mA total current drawn.
Correct if I am wrong in above calculations. I dont remember the exact current drawn, but will check it out tonight as soon as I get home.
(1000mAh/1000) / 0.300 A = ~ 3.33 hrs OR lets say both Rx and Screen draws 0.5A current it will be 2 hours.
And that is plenty of flying, if you have enough battery to fly your plane or multirotor.

Brother believe me the IC will turn hot. Its a 7808 IC from 78XX series n these ICs ve got the property of getting heated. I regularly work on these ICs. But U can apply a little Heat sink Paste n can also put up a small Heat Sink. BTW its a nice solution.

So what is the optimal solution in your opinion?
just simply use one 2S and one 3S battery? I mean this is really not a bad idea.
Because if you see only 300mAh batteries will last almost and Hour.

Bro at the end of my post I ve mentioned its a nice solution.

Still to protect your battery and also your electronics use a single battery and use a voltage alarm.
Its Simple and it works, I flew a lot today and had no problems at all.

I would consider not applying heat sink paste directly to component and leave it open without using a heat sink. The paste is just a medium to transfer heat from source to heat sink more efficiently by increasing the contact area. Heat sink pastes are electrically conductive and becomes more liquid on heating and hence flows which will create a havoc if flows over the contacts and creating short circuit. Best is to use heat sink pads like these: http://www.ebay.in/itm/15mmx10mm-cpu-heatsink-thermal-pad-premium-quality-2-pcs-15mm-x-10mm-/281261179743?pt=in_computer_components (http://www.ebay.in/itm/15mmx10mm-cpu-heatsink-thermal-pad-premium-quality-2-pcs-15mm-x-10mm-/281261179743?pt=in_computer_components) and use some small aluminium fins for heat sink.

Vijai every pc we use ve got Heat Sink applied on the back of its processor including the one u are using. This paste never melts or else U wld ve lost ur pc long back. Moreover I work on embedded systems n use these kind of things daily, n ve never seen Heat Sink Paste getting Melt, even for Years together.

Yeah I know PC uses heat sink pastes over processors and GPU. I never said it melts. It does get spread a little while heating. So applying more does cause issues. And even open heat sink pastes dont serve the purpose well as it does is gives a extra area to absorb more heat. And wont the paste just flow to the pads on pcb due to lot of vobration if left uncovered? There are lots of possibilities. Am I wrong?

Sir It gets dry day by day. I dint said to cover the entire ic with the paste. The back portion of the IC is aluminium there u can paste it. n one shld not put excess amount. Moreover its not conductive, I ve checked it by myself. I work on these things Sir so first of all I ve to be aware of the Properties of these materials.

 Heat sink paste is thermally conductive, not electrically. I even use the same thing when I change my soldering iron tips. If it does not "melt" in that application, no IC can melt it ;D

Hmm... i thought those contains aluminium in many compounds so its electrically conductive...

@Prateek I have used a similar setup using Airwave 5.8 Ghz module which requires only 5V supplied with a simple circuit with 7805 bolted to the large metal surface. With a large metal surface you can hardly feel both rx module as well as 7805 getting hot.

Prateek if u want I can build u a setup consisting of regulator ie 7805 n filter ie ( Capacitors Connected in Parallel Circuit). I often make use of this Ckt in embedded systems. Its a very small ckt bt I think ll solve ur problem to a great extent. Don worry bout the charge I wont charge anything, only U ve the Pay the Shipping cost.

OP I liked this mod so much, I had to do figure out the way.

Last night I did some experiments and found these.(Please see the attached pics!)

Issue 1 : Discharging Lipo under 3.7v

             > screen draws only 150mA
             > Rx draws only 200mA on 2S and ~214mA on 3S

             So even with small 1000mA battery you should get close to 170 minutes (Almost 3 hrs - Plenty IMO) run time.
             STILL LIPO ALARM IS ALWAYS A GOOD IDEA!

Issue 2 : Rx gets too hot on 3S. Cant power both Screen and Rx from same 3S Lipo.

            > miginstruments suggested since there are already holes on back of the screen,
               decent heat sink and/or small will do the trick. Gr8 idea but thing is we are trying to make it more compact.
            > Another easy solution is power both Screen and Rx with different batteries. But wht the hack we trying to
               make it look cool not bulky!  ;D
            > OR introduce the 12v to 8v circuit, with only 3 components and some soldering, but agian as miginstruments
               suggested we are facing the issue of over heating the IC7808. back to square one  :headscratch:

Issue 3 : Well not yet, let me create one.

            > so around 3:30 in the morning  :headscratch: I found this AMS1117 (http://www.advanced-monolithic.com/pdf/ds1117.pdf) on the circuit board of the screen.
               Its a simple low power voltage regulator. and as you can see below the two rails outputs 3v and 5v.
               So decided to use it to power the Rx with it,  :bow: praying i dont fcuk up anything on that board and it did work !!!!! ;D ;D ;D

(http://i1144.photobucket.com/albums/o483/chilschils41/2014-05-250328_zps368910cf.jpg) (http://s1144.photobucket.com/user/chilschils41/media/2014-05-250328_zps368910cf.jpg.html)

(http://i1144.photobucket.com/albums/o483/chilschils41/2014-05-25034116_zps4a2c7b2f.jpg) (http://s1144.photobucket.com/user/chilschils41/media/2014-05-25034116_zps4a2c7b2f.jpg.html)


             > SO NOW THE ONLY ISSUE IS ITS ONLY DRAWING ~138mA.

(http://i1144.photobucket.com/albums/o483/chilschils41/2014-05-25032755_zps73a49d5b.jpg) (http://s1144.photobucket.com/user/chilschils41/media/2014-05-25032755_zps73a49d5b.jpg.html)

             > I ran this setup for around 20 minutes, before one of the wire got loose. But nothing really got HOT.
                Actually the voltage regulator AMS1117 on the ckt board did not got as hot as it was getting without taking 5V out!
                

 ? But now the question is that 138mA gonna be a problem?
 ? Is it going to Lower the effective range of Rx?

well u shd do a bit of more research on the board ur uscurrentng. Check out for its rated current, it has to be greater than 138 ma. Moreover at this time the circuit behaves in a different. U ve to check out it in daytime. Tat time temp ll be more n may be the screen ll consume more power. But if its below the rated power then its fine. Now the question is to protect the lipo, so u can use an alarm to avoid max discharge. I spoke bout a fan, its pretty small n may get fit without consuming more space. Though it ll also consume some power but believe me heat is a great enemy of circuits. So u can afford to lose some power in order to protect the entire setup.

Running the Rx off that smd regulator is a bad idea.

Wow, Chils41 how come you didnt damage your Vrx, while using it without an antenna?Or is it only applicable on Vtx ?
And can that be the reason for reduced current consumption?

And I think that adjustable regulator is rated for 800mA.

EDIT
Just wanted to add, I think the Vrx too would be having a linear regulator onboard to get 5V, so wont supplying it with 5V be kind of undervolting it. Most of the 5V regulators need atleast 6.5-7V to work AFAIK. Moreover RC305 Vrx works within the range of 7V-12V.

Car cellphone chargers to convert 12v to 5v on my GCS setup...They're pretty light, do not get hot (smps, not linregs), inexpensive and easily available, deal with voltage spikes pretty well and are capable of delivering 0.5 amp easily, I've been running a raspberry pi with them on my diy GCS

http://www.rcindia.org/self-designed-diy-and-college-projects/flying-on-a-3d-joystick/msg163071/#msg163071 (http://www.rcindia.org/self-designed-diy-and-college-projects/flying-on-a-3d-joystick/msg163071/#msg163071)

Nice project. But please dont mind, you have a sloppy soldering. I would rather blame it to the ROHS compliant solder used in the Boards, which have a relatively higher melting point than the usual 40/60 solder we use form DIY/Repairs. Get a raw / brute sodlering iron of preferably higher watt and let it get heated covered inside a metal can (specially in summers we put fan on.)
Put some Flux and then gently touch the tip to the board and solder the wire. The result should have a shiny and blobby solder left on the board and not a dull 'Muddy'
I have spent days debugging such 'Dry Solders' on my PCBs during my early school days when I was getting into Electronics/HaM radio..

U can Use Sponge dipped in water to clean the tip of the Solder Gun. keep cleaning the tip after every single time u use the Gun. Also before soldering a point clean the tip, just rub it over the wet sponge. Moreover the Lead ur using is quite thin, i think tat is of Maxx brand, n it is used for soldering mobile phone ckts. Try to get a little bit thick Lead, it holds the soldering point pretty effectively.

It might be no doubt, but hey somebody gotta do it, so that other dont have to repeat same mistake.



Yes SideWinder, YOU MUST NOT POWER VTX WITHOUT ANTENNA, because it must output all that power via polarization. with Rx you are just fine.
And I THINK current consumption is still the same after hooking up the antenna. BUT WILL CHECK IT OUT AND POST IT LATER.
The regulator is rated for 1A, and I cant measure the current its outputting to the board without de-mount from pcb.

Yes the Rx also has 5v linear regulator onboard, and yes I am definitely under powering it with 5v supply.
And that is the main reason I want to do RANGE TEST to see if that made any difference.



you have one hack of a project there. very very impressive.
I tried to do something similar using Arduino, but programming USED TO BE my thing back in the days,

I guess first I have to brush up on that first, any way project was to use ball-bearing gimbles and some switches hook it up to Arduino
running Tx code, and generating PPM fed to Orange Tx module. Making your own custom Tx.

But hey thnx for the input.


Agree! This is my first time actually soldering something. Other than this I only have used solder to connect the Bullets to ESCs!!!
And I guess I need better solder iron. This cheap $3 menards one was just lying around. And yes the good soldering station is on my wish list.
PS: I never get that shiny solder, its always tht dull and muddy, I wonder the cheap Chinese 2% flux solder wire has to do something with it !!! :giggle:



You are ri8 man, I havent cleaned tht sucker forever, and using that I have made holes in Foam, plastic and wht not. so its very dirty indeed.
Dont know wht brand that is, cause all the letters r in chinese except it says 2% flux. but I will get some thicker material.




Thnx OP for this MOD and Thank you guys for all your inputs!!!

Yes sire, the water sponge is absolutely necessary and so is flux, the idea is to heat the surface and melt the solder on the surface rather than the tip flux helps remove the impurities and improve solder flow (you will automagically start getting shiny solders when all surfaces are clean)... if your soldering iron tip has gone black, get a new one, it should be shiny silver... And no melting flux directly onto the solder tip and absolutely no sanding of the tip :>)

PS: thanks for the appreciation, the project still has a lot of work left

LOL no sanding of the tip.

I was thinking about go home and clean it with wire scrub, i ll just get the new tip.
and I think I will get 60W iron and some flux as well.
You think I really need temperature controlled soldering station for this,
or just cheap iron will do the job, with nice tip and some flux.


PS: hey are you good with programming? I am talking about Arduino

Scrub it against the water sponge (let the sponge be completely wet in water), the moment you see some silver tip, melt some solder on it, and wipe again on water sponge, repeat and repeat, and you should soon have a clean tip again... You want the tip to be clean at all times, do not use flux for the cleaning process, it will make things worse and leave the tip tarnished

Temperature control, not really required, you might want to try soldering some other stuff first but for the project you're doing, a fine tipped should be alright. and you don't want the tip to be overheating the pad, thats where  the temperature control comes in :thumbsup:

there is a brand called Solderon ( Yellow in color) believe me I am using this Gun for years. This is one of the best quality Guns available in India. n keep two separate tips for soldering n making holes in plastic or else u ll destroy the tip.

Thank you both u guys girishsarwal  and miginstruments
I just ordered 60W iron, as now I am sure my iron wasnt getting hot enough to do the job.
and will pick up some extra tips on the way home since the old one is pretty messed up already.

and for now I m going to use two separate battery to power Screen and Rx.
by the time I receive the 12v to 8v converter IC, let me drill a couple of holes on the side, and break out those AV OUTs.
also a little hole on top to switch b/n channels.

 :iagree: on Soldron. Weller, Stanley, Tekton, J&L would be popular in the US
All the best

I dint really check tht, but THIS IS WHAT I ORDERED (http://www.amazon.com/60-Watts-Soldering-Iron-listed/dp/B0006NGZK0/ref=sr_1_1?ie=UTF8&qid=1401121846&sr=8-1&keywords=60w+iron) and it happens to be J&L. cool.

Oh and by the way this is the solder wire I am using
0.6mm 50G 65ft 63/37 Rosin Core Flux 1.8% Tin Lead Roll Soldering Solder Wire
Its cheap I kno, but hopefully its alri8.

(http://i.ebayimg.com/00/s/NjAwWDYwMA==/z/V2AAAMXQiFxR~J69/$T2eC16Z,!)sE9swm,1voBR+J68NpKw~~60_12.JPG)

63/37 Sn/Pb is alrite...

Good and HERE (http://www.amazon.com/Rectorseal-74026-3-Ounce-C-Flux/dp/B000IN1B8E/ref=sr_1_3?ie=UTF8&qid=1401123815&sr=8-3&keywords=soldering+flux) is the Flux I ordered.

Chils since you are at it you can as well try to bypass 5V regulator on Vrx. It may solve your 138mA current draw issue. It has been tried earlier so to speak.
http://www.rcgroups.com/forums/showpost.php?p=20996467&postcount=3 (http://www.rcgroups.com/forums/showpost.php?p=20996467&postcount=3)

kewl! Just what I needed.U made my day man.
So now all I need is good solder joints, which I think I will be able to since now I know a lil bit more about soldering.


Next few objectives in this project.

> Instead of TWO AV Outs, One more AV Out connected to Screen's AV2 In, so that screen can be used with something else!
> A Switch to power on/off the Rx, when in/not in use.

I do programing for 8051 but haven tried for fcb. I am thinking to ve some hands on tat too. But it ll take some time cuz am a bit tied up.

Got a lot to learn from this thread, thanks guys!

you ri8 bout tht man. But hey u the one who brought it up.
Its takes one idea to start the things, and many brains to make it work!

Chils, so I re-read the entire post with more time on hand..

1. Whats wrong with 138 mA or 200mA?

2. its pulling ~200-215ma on both 3s and 2s, so its rated for that. Current is a function of load, its pulled, not pushed into circuits. Imagine a rope on pulleys and a weight attached, higher the weight faster will be the movement of rope ... the load determines the current that flows, not the power supply  8)

3. It's getting hot with a 3s because the vreg has to get rid of 12v-5v = 7 * 200mA ~ 1.4W of energy vs 7.4v-5v = 2.4 * 200ma ~ 0.48W of energy. Put a fan, heatsink, necessary ventilation, all should be well.

4. Yes, the Vrx does have a linear reg inside, its min voltage is 7v, that is exactly what a 7805 needs to deliver 5v... see attachment, you can run safely between 7v and 12v. Check out the supply current  :thumbsup:

PS: yes I do program Arduino but I've always liked the AVRs the native way using assembly and C

Girish

If I'm not wrong when the regulator on Vrx (78M05) is supplied 5v, it would be supplying 3v theoretically to the Vrx because drop out voltage of that regulator is 2v. How would that effect the Vrx other than the reduced current draw.
Similarly would the decreased current draw have any effect on working of the Vrx itself? Whether that would have any effect on range/quality/sensitivity since its not emitting any signal itself.

Anyways having a cutoff voltage on the Vrx would have saved the lipos, which right now sucks the life out of them.

SideWinder,

Linregs need that minimum supply voltage, below that voltage, the output voltage will sag in a non deterministic fashion. The linreg will try to compensate by increasing the current pull (V=IR) from the source (for constant power P= VI) and that's what's happening here most likely, the rc305 is rated for 130mA but is pulling 200mA... the current would increase rather than decrease with a lower voltage..

Yes having a cutoff mechanism would save the lipos for sure, a low voltage alarm or a lipo voltage checker comes in handy


From wikipedia:

All linear regulators require an input voltage at least some minimum amount higher than the desired output voltage. That minimum amount is called the dropout voltage. For example, a common regulator such as the 7805 has an output voltage of 5V, but can only maintain this if the input voltage remains above about 7V, before the output voltage begins sagging below the rated output. Its dropout voltage is therefore 7V − 5V = 2V. When the supply voltage is less than about 2V above the desired output voltage, as is the case in low-voltage microprocessor power supplies, so-called low dropout regulators (LDOs) must be used.

When the output regulated voltage must be higher than the available input voltage, no linear regulator will work, (not even a Low dropout regulator). In this situation, a switching regulator of the "boost" type must be used.

http://en.wikipedia.org/wiki/Linear_regulator (http://en.wikipedia.org/wiki/Linear_regulator)


PS:
Almost all ESCs use 7805 for the BEC, (not the LVC - thats separate circuitry)

:headscratch: But Chils observations shows otherwise 214mA@3S; 200mA@2S and 138mA@5V

And the Datasheet you mentioned earlier is for the transmitter not for the receiver in question. You can find the specs @

http://www.hobbyking.com/hobbyking/store/uploads/109500705X727853X35.pdf (http://www.hobbyking.com/hobbyking/store/uploads/109500705X727853X35.pdf)

which states 150mA as supply current at 6.5 to 12V.

However my question is, if reduction in current draw would effect range/sensitivity and quality of video feed from receiver?

RC 305 all use the same chipset, bought from made-in-china or Boscam, the quailty of other parts, supply chain, value added services etc is generally what brings the price variations. Its like Intel Core i5 inside a Dell Vs Asus

Yes the reduction in current draw would affect the range, and most likely quality of feed... flickrs would be apparent. A field test would give better insight on what is the best range possible.

PS: The earlier spec sheet I posted was from a chinese vendor, so E&OE  :giggle: Probably they meant Transceiver

PPS: I stand corrected in my observation, it is indeed pulling more current on 3S, there have to be some other factors in play

Yeah, Chinese are good in mass manufacturing and stuff but there documentation most of the times needs to be taken with a grain of salt.

If Chils has successfully bypassed the regulator on Vrx, then everything should fall in place. The Vrx could be powered from Screen which inturn would be powered by Lipo. Bypassing regulator on Vrx should also help in reducing heat generated by the system(how much needs to be seen?). Best part ground station becomes portable and easier to carry around.

 :iagree: :iagree:

That'd mean pulling up a +ve and ground line from the 5v source and soldering it to the Vout and Gnd of the linreg in the Vrx and good to go

Guys ur forgetting one more thing. No matter from where he is taking the power, but there is another regulator in the vrx ckt as well. So even this regulator has got some drop. We ve to consider this drop as well.

Mig, SideWinder is suggesting to bypass the one in the Vrx... so 5 volt goes directly to the video circuitry

Alri8 guys, so after reading all those comments , these are the tests I am going to run.

1. First I am going to use BEC and bypass the 5vReg on Rx. and check the Current Drawn.
    Since BEC is able to supply upto 2A, this will really tell how much current Rx draws.

2. Power Rx with 5vReg from Screen ckt(w/ 5vReg on Rx bypassed) and check the Current Drawn.
    In my last experiment I dint bypass the 5vReg on Rx.

I brought all the stuff to work today, so if I get enough time to play around, will post some results soon.

PS: are you guys aware of some super cheap solution to record AV out from Rx? Or some simple DIY DVR ?

ok so I dint get much time to play around, but I made one very interesting discovery.

> As I mentioned in earlier post, there is 25v out on screen to power the backlight.
   Its actually not right, wait Kind of??!!!?!
   - it measures 25v only when you disconnect the screen.
     when connected it measures ~9.45v and ~5.08v when TURNED OFF using front power button.

Now that is pretty interesting cause, now I can power Rx w/o bypass 5vReg or any ohter modification.

so i will let u know how that works out, and how much it get hot stepping down tht ~9.5v and how much current it draws.

A compliant TV Capture card with video capture software...  It's not realtime, a slight lag always but alright for recording... The 305 has two video outs, useful to dedicate one to recording.

Oh we shd start a company. So many research orientated people.

ok so here is the quick update.
we are BACK TO SQUARE ONE  :banghead:, kind of.

first sorry as I couldn't post any updates for a few days, got so bz with work.

Anyway I got my new 60W Soldering Iron, and I am loving it.
you can see I did pretty good job this time compared to previous solders with 30W iron.

(http://i1144.photobucket.com/albums/o483/chilschils41/1_zps634edc5a.jpg) (http://s1144.photobucket.com/user/chilschils41/media/1_zps634edc5a.jpg.html)

Any way let me cut to the chase here

>  Powering Rx from that 9.5v/25v supply [which also powers back light of TFT screen] DID NOT WORK.
    It dose provide enough power but not current(~106mA) and as soon as I connect Rx, it shuts off the screen Back lights.
    So to say, 25v drops to 9v when you power on the screen, but its not sufficient to power both Rx and screen at the same time.

(http://i1144.photobucket.com/albums/o483/chilschils41/4_zps0ea67b4b.jpg) (http://s1144.photobucket.com/user/chilschils41/media/4_zps0ea67b4b.jpg.html)

>  So again we are back to power the Rx with that 5v regulator AMS1117, but this time bypassing the 5v regulator on Rx.
    Nope that dose not work either. It shuts off the screen as soon as you power the Rx with it.

(http://i1144.photobucket.com/albums/o483/chilschils41/2014-05-30020648_zps2ac13440.jpg) (http://s1144.photobucket.com/user/chilschils41/media/2014-05-30020648_zps2ac13440.jpg.html)


>  So as before I powered Rx with 5v AMS1117 through the on board regulator, and again it draws ~139mA as we already know.

(http://i1144.photobucket.com/albums/o483/chilschils41/3_zpsee4a4232.jpg) (http://s1144.photobucket.com/user/chilschils41/media/3_zpsee4a4232.jpg.html)
   

So this gives new objective here, TO DO THE RANGE TEST!
which I plan to do this Sunday.

One thing for sure is Rx needs or it draws ~200mA when powered up using 2S(dosent get too hot) , and a bit
more ~215mA with 3S(gets pretty hot), so ~200mA is ideal current required.

IMO best bet is put a tiny BEC/UBEC inside the Screen casing, where the holes are, and that will do the trick.
BUT THE RANGE TEST WILL BE REALLY NECESSARY BEFORE THROWING EXTRA STUFF ON THIS MOD.


PS: crashed another one last night,(I am complete noob  :banghead: but will get there) and that 30Amp ESC
      dose not seem to be working. I dose powers up 6ch Rx and the control servos but not motor.  ???
      so I can use tht as BEC and do the LAST test!!!

<peace>

I'll do that as soon as I am back home.
I have an easycap, it should work just fine

check this out,
Better option than dealing with video capture software, n computer n stuff on the go.

LINKY (http://www.ebay.com/sch/i.html?_odkw=mini+c+dvr&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR2.TRC1.A0.H0.Xmini+c-dvr&_nkw=mini+c-dvr&_sacat=0)


(http://i.ebayimg.com/00/s/MTAwMFgxMDAw/z/4AYAAOxyzqdTdBlG/$_12.JPG?set_id=880000500F)

chils it will be easier to get one of these as a dedicated power supply for your rx...rush to the closest walmart and get rid of your worries. No messing with the screen... one bad connection and poof it goes

http://www.walmart.com/ip/INSTEN-Black-USB-Mini-Car-DC-Charger-Adapter-2in1-Micro-USB-Cable-For-Cellphone-Mobile/36616147 (http://www.walmart.com/ip/INSTEN-Black-USB-Mini-Car-DC-Charger-Adapter-2in1-Micro-USB-Cable-For-Cellphone-Mobile/36616147)

Chils, also the C-DVR is a lovely option... its hard to get locally in India.. capture cards are available at every round the corner store...

Prateek, some of those need external power supplies via USB hubs to work properly.. It took me three days realising that with the raspberry pi.

chils, howz this going on? still onto it or have I spread my half completed endeavors disorder to you ....lol

i have cdvr for sale if interested let me know

Hey guys, its been long time since I have been here. Got so busy with work and family.
But I was still working on this project little bit at a time. And I guess I figured out pretty good way to integrate everything in one compact package.

Check out the video below, of the complete build.
If any suggestions please let me know. Thnx. :hatsoff:

http://youtu.be/XSbSGq9RyJ4

Here is some pics!

(http://i1372.photobucket.com/albums/ag359/scratchbuilds/DIY%20FPV%20Ground%20Station/CIMG1033_zpst8ekgjw2.jpg) (http://youtu.be/XSbSGq9RyJ4)

(http://i1372.photobucket.com/albums/ag359/scratchbuilds/DIY%20FPV%20Ground%20Station/CIMG1037_zpsgldzdwc5.jpg) (http://youtu.be/XSbSGq9RyJ4)

Back

(http://i1372.photobucket.com/albums/ag359/scratchbuilds/DIY%20FPV%20Ground%20Station/IMG_20150118_194318-nopm-_zpsqdov8p3v.jpg)

Internals


(http://i1372.photobucket.com/albums/ag359/scratchbuilds/DIY%20FPV%20Ground%20Station/IMG_20150112_194854-nopm-_zpsf5klmvhs.jpg)

Nice mod  {:)}. Could you post some internal pics after final assembly.

Thnx. Uploaded more pics!

So the power supply to Video Rx is from 2S lipo or from the 5V regulator on the monitor pcb as shown in earlier pics?

No, now 2S lipo is connected straight to both Monitor and the Receiver. Say in parallel.
The entire system is drawing about ~540 mA.
If you run just the Monitor it draws ~320 mA and if you run only the receiver by it self draws about ~260 mA.

I am trying to find the picture of the Connections Diagram I made.
If you get chance, take a look the YouTube Video that I posted.

had to get outta bed and take a picture again. here you go

(http://i1372.photobucket.com/albums/ag359/scratchbuilds/DIY%20FPV%20Ground%20Station/20150225_014805_zpspgdv0e1t.jpg)

Nice DIY Skill . keep it up  {:)}

Can you specify the Lipo pack, is that from transmitter pack? or ripped from Normal Lipo for Flights?

Did you checked the cells for Tablet PCs(LiPo/LiIon). is light weight, thin, safe and holding more Juice.

I had a 1300mAh 3S Lipo lying around whose one cell got puffy.
So I carefully took part 3 cells, used two of them for the mod. (the puffy one was thrown into BestBuy's battery recycle!)

But I suggest using upto 1000mAh battery, because that 1300mAh was a bit bigger, and I had hard time closing back cover. I still have little bit of crack at the bottom. You can see it in the video I posted on YT.

1300mah? then you can consider two LiIon batteries from mobile will save more space.

very interesting! I think I have some old flip phone batteries.
I will give it a shot in a day or two. I still have to integrate one very important thing though.
Battery voltage alarm. So that is my next goal.

Look at this, 1500mah LiPo (Original From Sony)