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[Purgatory]

Hi everyone - I'm new here (first post) can you help/advise on the following. I am building a boat with twin screws (opposing directions)
I am using 2x Johnson 600 motors (in series)

I have an old but working Acoms AP227mk11 system - questions as follows -
Can I use rechargeable batteries in this old gear?  I seem to recall from the distant past that it did not like the reduced voltage?
Can I use a modern speed controller? (In place of my old MACGREGOR MR15)

I use 2x 6v 4A batteries in series, and both motors are rated as 6-12v. Obviously channel 2 will be used for the steerage/servo.
Am I just wasting my time trying to use this old gear? OR will it wotk.
Thanks in advance for your valued comments.
Cheers
Purgatory

[triumphjon]

there is no reason that your 27 mhz radio wont work with more modern speed controllers or mixer units , it should be good enough to get you back into the hobby , however should you feel the need for updadting your radio equipment the current range of multi channel 2.4 ghz sets offer greater possibilities of working functions on a model for very similar cost to that of a two channel set . there are several good clubs in your area who would be able to assist you further

[grasshopper]

Don't see why not.....
You have a source to power the radio if you're using a pair of 6v batteries, power your radio from one of those. Alternatively, get a 5 cell rechargable pack which will give you 6 volts.
Check that your intended 'modern' speed controller has a BEC (battery eliminator circuit) if it does then you won't have to worry about powering the receiver end as it will be supplied by the new ESC.

Would you be better off with your motors in parallel - that way they both receive the same voltage, you can still wire for  contra-rotation.

You can always try this equipment first and see if it works - just make sure that the three wires going from any new servo, ESC and into receiver are the correct way round and that the common(black), positive feed(red) and signal (white) are correct for what you're connecting to - with any 'older equipment' there may be some differences compared to the latest gear.

Any other questions,  just ask there's an awfully large collective knowledge on here. Best of Luck.

If you were to go to the expense of new equipment aim to purchase the new 2.4Ghz gear (unless you're into submersibles) so much better than the old AM /FM stuff.

[essex2visuvesi]

I had the AP227Mk 2 and it will run happily with single cell AA nicads or nimh.  Just grab a couple of packs from your local poundland.  The only downside is that there is no charging jack so the batteries will have to be removed from the controller, tho you could always fit one if you're handy with a soldering iron :)

One small problem is the connectors from the receiver to the servo, they are not easy to find anymore

No reason why you cant upgrade the speed controller to an electronic one
I had this in my bookmarksl that you might find helpful
http://www.tamiyaclub.com/forum/index.php?showtopic=46175&pid=293017&mode=threaded&start=#entry293017

[Purgatory]

Thanks guys for the benefit of your thoughts. This forum seems to be well sorted with many helpful people - glad I found it!
Grasshopper - I did think of running the drive motors in pararell HOWEVER, I was rather put off by the following info from the net -

Referring to a pararell setup -
"This type of twin motor wiring setup (series) will yield high speeds but short runtime. This setup will also most likely blow your motors, esc or bake your batteries! On the above wiring setup each motor will get to use the full voltage of the battery pack".

Referring to a series setup -
"This type of twin motor wiring setup is the most widely used in fast electrics. A series set of motors properly setup will be fast and yield long runtimes. On the above wiring setup each motor will see half the battery pack voltage."

What does everyone think about the above comments?
Cheers
Purgatory

[grasshopper]

What sort of boat are you building and what type of performance are you hoping to achieve?

[Purgatory]

Ho Grasshopper
I am building a Type 42 destroyer  (52") - therefore speed is not of the essence - hope this is of help

[grasshopper]

If it was me doing a model like that I would be tempted to go multi-channel and fit independent motor and speed controllers for manoeveurability.
With the design of the hull I still think that two 6 / 12 volt motors in parallel would do the job as long as they don't exceed the speed controllers max. current ratings. Your quotes were for a 'fast' electric - wouldn't class a 52" type 42 as one of those. Can I assume the props would be large diameter but low pitch ? that should keep the current down as well.

[unbuiltnautilus]

Hi, the old Techniplus II receiver is wired up 'backwards'. with these old units, if you plug in a more modern servo, speed control etc without rewiring the three pin plug, invariably you will stuff the servo/speed control and the receiver channel. Be careful, I cannot remember which way round these plugs go as they are configured 90 deg off of more modern equipment. However, if you still have the old plugs or better still, servos or battery box, use them as a guide to reconfiguring your newer equipment. Hope this makes sense?

[Mankster]

Thanks guys for the benefit of your thoughts. This forum seems to be well sorted with many helpful people - glad I found it!
Grasshopper - I did think of running the drive motors in pararell HOWEVER, I was rather put off by the following info from the net -

Referring to a pararell setup -
"This type of twin motor wiring setup (series) will yield high speeds but short runtime. This setup will also most likely blow your motors, esc or bake your batteries! On the above wiring setup each motor will get to use the full voltage of the battery pack".

Referring to a series setup -
"This type of twin motor wiring setup is the most widely used in fast electrics. A series set of motors properly setup will be fast and yield long runtimes. On the above wiring setup each motor will see half the battery pack voltage."



What does everyone think about the above comments?
Cheers
Purgatory

That’s not right. If you are wiring your 2 6 volt batteries in series you have in effect 1 12v battery. If you wire your motors together in series, each motor will get 6 volts each. Each motor will however  have to draw twice as much current in order to do the same amount of work compared to the same motor running on 12v. Also if 1 motor stops working you will not have use of the other.
You first need to decide if you want to run your motors at 6v or 12v. Then you need to wire up your batteries to reflect this voltage. Wire in series to get 12v or in parallel to keep it at 6v. Then wire your motors in parallel so they get the correct voltage and can be run independently (to give you better control or still have the use of 1 motor should the other fail).

[Purgatory]

Thanks everyone for your comments
following your advice, I think that I will in fact run the motors in parallel. I will then try both a 6 volt/12volt supply option to see how it goes.
Thanks everyone

Purgatory

[RaaArtyGunner]

Simply put in referring to parallel in this instance, are we saying both motors connect direct to battery pos and neg but one motor is wired for opposite rotation, neg battery to pos motor terminal, pos battery to neg motor terminal and thus contra rotating props ?

[Purgatory]

Yes I intend to put one motor on opposite feed to get contra-rotation.
Purgatory

[malcolmfrary]

Some old RXs have a socket rather than a set of pins, but are in the same order as modern equipment.  The servos for these had pinned plugs, rather than line sockets as the modern gear.  Conversion is a simple matter of creating pins by using short lengths of appropriate thickness wire.  As long as the +, -, and signal wires turn up in the right respective places, no problem.

Referring to a pararell setup -
"This type of twin motor wiring setup (series) will yield high speeds but short runtime. This setup will also most likely blow your motors, esc or bake your batteries! On the above wiring setup each motor will get to use the full voltage of the battery pack".

Referring to a series setup -
"This type of twin motor wiring setup is the most widely used in fast electrics. A series set of motors properly setup will be fast and yield long runtimes. On the above wiring setup each motor will see half the battery pack voltage."

What does everyone think about the above comments?

This might be correct in a very particular context, but generally, the statements are totally incorrect.
Run on 12 volts (two 6v batteries in series), the 12 volt motors will each give their intended power if connected in parallel.  They will each draw their full current to achieve this, and the prop(s) will determine this.  If one ESC is used, it will need to be able to handle the full current, lots of threads covering this.
In series, each has effectively a 6 volt supply, half the voltage, half the current, therefore, one quarter the power each, and performance to match.  If one of the motors is stalled, its resistance drops greatly, and the other gets full power, gets hotter, and has a good chance of turning the boat in circles.
Connecting one motor in reverse is the way to get counter rotating, but remember that this needs a left hand prop and a right hand one.