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[catengineman]

Hi, fellow modelers,

(grovel grovel) knowledge required before I fry / zap or whatever you do to receivers if you get the pin connections wrong.....

Now I may be in some sort of mental block as to the pin configuration of a receiver but, are all the + ve pins common
and therefore all the - ve pins would be common as well this would leave only the 'signal' pin being one that would require wire to a servo, if the servos were linked in a power ring system.

What I mean is if 5 volts + / --  is supplied to (lets say 4 servos) via common leads to the "red / black" terminals then the corresponding signal wire from the receiver to each servo (1 wire instead of 3 per servo) so long as the receiver has an input of 5 volts the servos will work?
OR will it all fry? ???

It's just an idea that I was toying with to reduce the amount of wire and contacts I require between my accommodation block and the hull of my model.

Richard,

[Faraday's Cage]

Hi Richard,

I think in theory your idea should work and as you rightly say, all the positives and negs on the rx are linked out.   I would be inclined to take the 5 volt supply from the rx to feed the power rail that way you will be keeping your 5 volt supply common with your other radio functions within the model.

Never tried it myself so cant speak from experience.

Let us know how you go on.

Terry.

[catengineman]

Hi, Faraday's Cage,

Thank you for the vote of confidence as to what I think I can do with the system (cant spell circuit) it was just that I have run out of terminals between the accommodation block and the deck (hull) sockets.
I have a home made power supply that will deliver the 5 volts to the receiver this in turn (at the moment supplies 7 channels) all but 2 are used in the main hull of the boat, 15 cables and terminals (I think) out of that I could, If using common circuit or ring main idea cut the required amount down to 9, (I think) (crap at math)

Any way a new receiver cant be that costly if I do loose the smoke out of the wires through fiddling with it.

Richard, (with fingers crossed)

[malcolmfrary]

Yes the pwer supply pins are common, and the arrangement described should work without any hassle, but make sure that the ground line (-ve) is good and meaty - this is to ensure that the voltage variation on the -ve connection at each servo is minimised.  The electronics in the servo uses this as a reference when sorting the signal from the receiver, and a very small variation due to loading (more than one servo motor running) can create unpredictable, but probably small, reactions.

[catengineman]

Thanks,  Malcomfrary,

 I am off to 'work' now so I'l have lots of time to resolder all my joints with the new circuits and I know just where to get some reasonable wire for the --ve feed.
(ships stores do come in handy some times) 

See ya all in two weeks or there abouts.

Richard,

[catengineman]

Hi out there,

 Well thickO is asking yet another question regarding power supply for the receiver in my tug (and any other model for that matter)

 I know I want 5 volts for the rec and servos which I can get from my stand alone power supply or BEC from the ESC

can any one tell me why I can not use two ESC with the BEC pin left in the plug?
== The ESC delivers 5 volts via red /black wires  if you put two +ves together & two -ves together there is no increase of power it stays at 5 volts

A bit like jump starting you car two supplies but the voltage is still only 12 volts (amps increased) longer useage time.

The reason I'm asking this is I have a drop in servo speed which I think I am asking too much from the power supply

I may have this all wrong when it comes to this low voltage stuff and using one leg to complete a signal circuit etc, give me 440v 185 Kw then parallel two units (easy)

Richard,

[Shipmate60]

Because the BECs are made within a specification and one will be slightly higher or lower than the other.
The higher voltage will try and charge the lower BEC and will blow a transistor rendering it u/s.

Bob

[catengineman]

Thanks,

                                                                                                             untill the next daft question

Richard

[Miss Sinbad]

Richard, I ran into a similar situation as yours some time ago. So PMK came up with a couple suggestions.
As Faraday's Cage has said, each servo positive supply rail is connected internally at the receiver. Same thing applies for all the neg. supply rails - they too are connected internally.
I simply snipped the 3-pin plug from each servo, then connected them as shown in the following attachments.
The 2nd attachement is similar to the first, only I found it more convenient to retain the yellow wire in servo plug, but re-route the pos. and neg. wires to just two 2-Amp connectors.

If you need wire, might I suggest you give PMK a holler. I know he has miles of the stuff.


Good luck with your project.

[catengineman]

Thanks Miss Sinbad,

      Here I am sat back at the desk 100 or so yds away from my tug (at the moment the best place for me)
So I can remove all but one of the plugs red/black wires and redirect them to a separate supply.
would this now mean I still have to route the neg (black) wire from my power supply through the rec?
I may have this all round robbin but as I sit here I cant work it out I still have the same power drain though it will not now run through the receiver.

May-be I'm not meant to work on models?

Richard,

[Peterm]

The diagrams that Miss Sinbad are superb, but surely the simple answer is just to cut the RED receiver lead on ONE of the ESC`s.   Pete M

[catengineman]

I agree that the diagrams are very good but I feel there is a slight miss reading of the problem,

I am at the moment not using any of the BEC power as I have an outside power supply this though is as I have found out not strong enough to power all the items I have fitted into my build.
I did try to use one of the BEC system power supplies but this also showed the same problem in voltage drop as the various units were turned on (reinstated) to the system.
I therefore thought that I could possibly use two BEC power supplies to possibly overcome my problem.
on another project I did try to "up" the power to the rec and therefore the servos etc but ended up with a fried rec and some smelly servos :'(

I hope that this will help in sorting this small problem out, its either that or a tug with lots of fixtures that are not operational.

Richard,          despondant depressed and going back to cooking

[Miss Sinbad]

Maybe the clue to your problem is in your homemade power supply. What exactly is it?... a battery pack... mains transformer... what? I assume your homemade PSU is pumpnig out the correct voltage, but is it capable of delivering the needed current? What happens if you hook up a standard 4-cell battery pack?
My Rx - same as yours -  is also 7-channel. A standard 4-cell battery will power all seven channels without any detrimental effect to each servo. So I'm guessing that your homemade power supply maybe isn't up to the job? I'm also guessing that your PSU is indeed derived from a mains transformer, and if that IS the case, then you want to be sure that the output is sufficiently smooth, filtered AND capable of delivering the required currents.
I am merely stabbing in the dark here, so please correct me if I'm barking up the wrong tree.

I am not sure of the current rating of your BEC. But since you're using just four servos, then the BEC (just one of them) should work just fine.
As a personal preferance, I prefer to employ a separate Rx battery rather than rely on the BEC. But that's evading the issue. Feel free to holler if you need more sketches, etc. But please be a little more specific in what you are doing. Maybe a wee sketch of how your wiring system is?

For the record, the sketches weren't drawn by myself. PMK mailed them to me a while ago.

[catengineman]

Here I have a quick sketch of my stuff.

The power supply was made by me (taken from www.keirle8122.fsnet.co.uk-gadgets)

The numbers on the drawing are as follows:
1    Stbd steering servo
2    Stbd drive ESC
3    Port drive ESC
4    Port steering servo
5    Robbe duo switcher (bow thrust)
6    Servo converted to run 360 deg  (anchor winch)
7    Robbe duo switcher latching (esc cooling and fire monitor pump)
8    Robbe duo switcher latching (steaming lights and radars)
9    Robbe duo switcher latching (change over for towing winch control)
10  Towing winch ESC

 The power supply delivers 12 volts which is through ESC (10)
 The power supply delivers 5 volts to the lighting circuit driving grain of wheat lamps
 The power supply delivers variable volts to the radar drive motor
 The main drive ESC's have the red wire removed from the plugs
 The receiver power supply has been from the towing ESC which in turn supplied the rest of the system....
 I have tried a set of batteries in stead of the ESC but I find that there is still a large power drop which is where I would like to find a cure


Richard,

[Peterm]

You do seem to be running a lot of items from the power supply.   Once again, not much help, but it might be that your power supply is just not up to it.   Remember, in a power supply it is its voltage AND current capability that have to be up to scratch.

[catengineman]

I may be saying this wrong but the home made power supply only serves the lighting on the 5 volt
It also serves the radar on a variable
It also supplies 12 volts for the towing winch esc

I have tried a battery pack to run the circuit instead of the supply from the towing winch esc

Richard,

[Shipmate60]

If I have it correct the receiver is only running 3 servos, the Esc's take milliamps.
There must be a high power drain in there, possibly the winch servo, couldnt you try that one disconnected and if all is OK fit a separate power supply to this, or even something like a 6v 3Ah battery to power the 6 volt auxiliaries?

Bob

[OMK]

Don't wish to imply anything untowards, but do you suppose there might be a fault with your power panel, or maybe an error has crept it while you were building it?
If you copied and built it exactly as shown, then it should work right off the bat.
Did you paste the parts-placement overlay to the board? Without it it's too easy to get a wire link or component in the wrong location.

What happens when you by-pass the power panel altogether?

[HS93 (RIP)]

I think its time to play with the amp meter,isolate each item and see what is taking the current .as a start just see what its drawring overall from the battery ,you will find out straight away if its the power panel.  peter

[catengineman]

Thank you all for the input to this small problem,

I have stripped out the electrics from the tug including all the servos and switches sat them all side by side on the bench, power from a battery pack I see no drop in operations but there again there is no strain on any of the items.

I have tried several permitations to power the system
1 with my PSU
2 with a battery pack
3 from an ESC
4 from a 6 volt SLA battery

So with all this in mind I am giving up and going to work for three weeks.
I may end up with static winches, anchor and no fire monitor pump on this build (wreck)

Richard,

[catengineman]

On the subject of pins and power supply I have resolved one problem, only to find another though the later I feel is possibly down to yours truly having dabbled with things he should have left alone.

It is very easy to power the recever and the servos from a an outside power supply (no BEC and not silly little ni-cad batteries either)
 I have 6 volt running in a ring system through all the tugs items * steering servos, anchor winch(converted servo), latching switcher, two ESC's, bow thrust ESC (converted servo), Fwd winch switcher/fire monitor-cooler pump.* the signal wires then run to the respective items and it all works fine in the tug.

So now the only problem I seem to have gained is there is no distance to the tug before the systems (receiver) loses contact with the transmitter IE: tug throws a wobbly and does whatever it feel like doing at the time until I or IT is closer and the signal to the rec is regained.

Ariel is normal length etc..?

Richard,

[OMK]

Dude, for someone who's trying so hard, you really do deserve to get that ship on the water.
Can I ask just ONE question, first?
Could you post a sketch, or a photo?
Sometimes, a picture shows what words can't.
Seems you've tried just about EVERY which way.  Man, you deserve a medal just for hanging in there so long. And still you're having no luck.
Sometimes a picture can reveal something you might have forgot -- even the stupidest things.
If not, let's take it from the top, start over, one wire at a time.

[Faraday's Cage]

Hi Richard,

Its probably going to be a process of elimination.  Is it possible to disconnect your auxillary functions (switches, winches etc) and just leave sterring servo and esc's connected  ?  Either way, the result will narrow the problem down by half.  If this test is successful then continue to reconnect the rest of the functions with a further test at each stage.  If not successful then I would check the receiver, xtals, and esc's.

Terry.

[catengineman]

To All,

Thanks for the assistance with my 'little' problem,

Todate I have a working tug! (yes capt jack) a working tug and there is the good news.

So long as I only operate it within 15 meters LOS then every item in or on the tug operates correctly
IF the tug and I are any further away then      deep sadness     tears    frustration      anger   rude words
well that is unless by shear fluke the tug wanders back within the afore mentioned range tears of joy      jubilations    big smiles
but whats the chances of that happening doh!

So lads and lasses I thank you all from the bottom of my heart (not the lake YET) and from yet further testing I have found out that it is MY receiver which has given me hours of unpleasure and extra expense.
I borrowed a six channel receiver and lost sight of the tug before the control was interupted or went t##ts up so to speak. and with this new info in hand I will now start to save some hard earned dosh to obtain a replacement receiver with enough channels to fit the bill.

On a lighter note does anyone make a 10 channel receiver? I only seem to be able to find 8 channel ones, though looking in the right is not one of my strong points.

Richard,

[Faraday's Cage]

Hi Richard,

Glad to hear you've resolved the puzzle.

On a lighter note does anyone make a 10 channel receiver?

Wouldnt be any good unless you found a 10 channel transmitter. ::)

Terry.