Model Boat Mayhem
Technical, Techniques, Hints, and Tips => DC Motors (Brushed) and Speed Controllers => Topic started by: Marty on May 17, 2015, 08:04:53 pm
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Hello Guys
I've just installed a P94 into my tug and just fired her up.
I'm finding that the when using tank steering mode the follwing happens.
When i push the left stick forward the left motor runs correctly, when i push the right stick forward both motors run the left maybe half the speed of the right. When i move the right stick left and right the rudder moves correctly.
Just want to be clear I've selected Mode 1 on the small selector, both switches pushed towards the heat sinks.
Any ideas anyone.
Cheers
Martin
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What Radio set are you using?
Bob
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I'm using a tactic TTX650
You think that could be the problem?
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No idea I don't know that radio set.
Bob
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Is it an air set, plane or heli as sometimes on the other sets can upset the set up.
Bob
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Here you are Bob
http://www.towerhobbies.co.uk/products/tactic/tacj2650.html (http://www.towerhobbies.co.uk/products/tactic/tacj2650.html)
Dave
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Thats the one Bob!
Im going to try another radio set tomorrow, see if its the culprit!
I've not had much luck these past few days with ESC! :((
Marty
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The P94 is not compatible with some 2.4 radio sets. The Action P94 Data sheet states 'THIS PRODUCT IS NOT COMPATIBLE WITH FUTABA 6J OR SKYSPORT 2.4GHZ RADIO SETS'. Don't take my word for it, but the TTX650 may be afflicted the same. I think INERTIA is your man for a definitive on that one.
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I'll go have a look see what i can find.
I use the tactic with my tug running the mtroniks esc, and its a dam good unit.
Think its time to change and wack the tactic on ebay
Marty
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I'm finding that the when using tank steering mode the follwing happens.
When i push the left stick forward the left motor runs correctly, when i push the right stick forward both motors run the left maybe half the speed of the right. When i move the right stick left and right the rudder moves correctly.
The P94 incorporates a mixer. This takes its instructions from the throttle channel and the rudder channel, and mixes them to give the required result. From the description, it sounds like the right stick throttle is connected into the system. It shouldn't be. Sideways movement of the right stick should not only move the rudder via the through connection, but should also drive the motors in opposite directions. Pushing the stick forward should do nothing.
Since hardware mixers are intended to be used in the first place with very basic sets, it follows that any transmitter that has any programming capability will only confuse matters if it has programming modifying the steering/throttle responses.
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In mode one the two esc's should be independent I.e.tank steering.
If you are in mode one and getting mixer outputs from the p94 it would
indicate a fault of some sort
Ned
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I would have suggested testing the thing in Mode 1 but it's that which is giving problems. If you can check it with a different radio set then that will confirm whether or not the problem is with the P94 or the radio. If you believe the P94 is at fault then please let me know via PM and I'll let you have the address to send it to (I test and repair ACTion units for Component Shop).
Dave Milbourn
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I just re-read your original post and I'm struggling to work out why the P94 should behave like this. I'm inclined to think it's the radio:-
It's a fact that many of the cheap Chinese radios have very different degrees of movement and centres on the throttle channel than they do for the other three. If you can leave the LH stick centred and push the RH stick forward, does it have any effect on the LH motor? If not then there's likely no problem with the P94. Try these two tests, but first disconnect the P94 altogether:
To check the centring, plug a servo into the rudder channel, switch the set on; set the rudder trim to centre and allow the servo to centre itself. Then, without touching the servo disc, unplug the servo and replug it into the throttle channel. The disc shouldn't move. If it does then there's a centring issue. It might be possible to rectify this with the throttle trim lever, although this lever has no effect on some makes of radio.
Now repeat the performance but this time push the rudder stick all the way to the left and right and mark the angle through which the output disc moves; then try the servo at full stick deflection in the throttle channel. I'd bet my boots it doesn't move as far. If there's a marked difference in the degree of servo travel then check the End Point Adjustment on the two channels - it should be 100% each way on both. Flip the Elevator Dual Rate switch and see if that affects the throttle travel. Make sure that the Exponential movement on each channel is the same (I'd suggest none). This looks like a pretty complex radio but looks aren't everything.
The moral is, as always, buy a decent known radio set in the first place. You can't go far wrong with Futaba, Hitech, Spektrum or even Planet.
As I often say, suit yourselves.
Dave M
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Hello Dave
First a thank you for the above advice, very good test!
Let me start by saying I'd spoken to Neil Lewis from action today and he seemed to think that there's possibly a problem with the P94 and asked that i return the unit to give it a once over.
Dave I ran your test on the radio gear and I found the following:
I plugged the receiver into the rudder channel and centered the rudder using the adjustment tabs as you requested, i unplugged the rudder and plugged it into ch 2, the servo moved just a couple of degrees.
I unplugged and transferred it into ch 3 and tried the same. The servo moved only a few degrees.
When i moved the sticks the difference in movement between each axis was only slight, really hard to see exactly how much diffrence between each axis is present.
When i spoke with Neil from action today and described that i was getting movement on the Lh motor when using the Rh stick he was quite sure it was the P94 and wanted it sent to him for further investigation.When i installed the P94 in the tug the first thing I always do is zero all controls and center the sticks, my radio always asks me zero all throttles.
Dave thanks again for your help! I've learned a great deal tonight about my radio gear. I'm looking into buying a new Futuba set. Can you recommend a good set. Today i was looking at the 8 series's, i forget its exact model numer?
Cheers
Martin
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Martin
It would be Iain Lewis you spoke to; there's no Neil there. If he asked you to send it back there then please do so. He is The Boss.
I can't personally recommend a Futaba set except the now obsolete 6EX. Some of their more recent sets (e.g. the 6J) are not compatible with the P94 - for reasons which are too complicated, dull and tedious to go into here. I haven't handled all the current models so I can only rely on what I already know. Maybe there are others out there who happily use a newer Futaba set with a P94 - hey, guys; Martin would like to hear from you!
My own day-to-day set is a Hitech Optic 6, although the Spektrum Dx6 and Dx6i also come highly praised. If you want a less complicated radio then the Planet T5 is very popular - although it's not computerised, has only 4+1 channels and has limited range. All of these work fine with P94.
Dave M
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Dave
Will The hitech optic 6 definitely work well with the p94 and other action systems?
I've had a look online and I'm quite impressed with the kit!
Martin
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Sorry Dave I've just seen the last part of your message! :embarrassed:
Thanks for the help.
Martin