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can you use a stationary decoder on a modified servo motor?

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  • Member since
    October 2011
  • 3 posts
can you use a stationary decoder on a modified servo motor?
Posted by hoscale on Sunday, October 30, 2011 9:00 AM

Is it is possible to use stationary decoder for remote turnout control on a modified servo motor?

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Sunday, October 30, 2011 4:04 PM

 If you mean modified per the article from a few months ago, I still say don't do that, servos are not meant to stall. The current draw is is higher than most stall motors, which means most stationary decoders won't support the steady state current draw to run a servo modified to be a stall motor. The CVP ones are about the only ones that can run stallmode plus high current like a solenoid.

Do yourself a favor, look at the controlelrs from Tam Valley and use those, with unmodified servos. They give local control with indicators plus are DCC stationary decoders, and operate the servo the way it was meant to be operated. I'm using the Singlet devices on my layout, the Quad is a bit cheaper since it combines 4 controllers on one board. The Octopus is is the lowest cost per turnout, but does not have a DCC decoder as part of it. As for actual cost, the Singlet cost about the same as one Tortoise but that includes the mechanism plus pushbuttons and LEDs and a DCC decoder.

                          --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
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  • 3 posts
Posted by hoscale on Monday, October 31, 2011 9:18 PM

Thanks.  For the tam valley controllers do they include the servo, or are they just a stationary decoder?

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Tuesday, November 1, 2011 5:24 PM

 The Singlet is available as a complete kit, including the server, however I buy servos from one of any number of Chinese vendors on eBay, less than $3 each. I also buy the Singlet kits, all you actually have to assemble are the pushbuttons and LEDs, it takes about 30 seconds to assemble the 'kit' and they are $2 or so less than the assembled ones.

 The Quad and Octopus do not include the servos.

                --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    October 2011
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Posted by hoscale on Wednesday, November 2, 2011 5:37 PM

Thanks for the advice.  Do these kits come with frog juicers? If not are they compatible with a comercial frog juicer like Fast Traks'  Hex frog juicer.

  • Member since
    January 2011
  • 11 posts
Posted by schulzie on Wednesday, November 2, 2011 9:22 PM

im my experience the best servo has been from hobbyking. I flown rc for 7 years now, best value/quality servo is hxt900. They have worked wonders on most of my planes.  But if you want to spend less cash look at the TG9e's.

  • Member since
    May 2008
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Posted by Hamltnblue on Wednesday, November 2, 2011 9:26 PM

RC Airplane servo's are good but probably major overkill for what you need to do most tasks in MRR.

As noted earlier the Tam valley servo's are cheap, strong and will do most tasks.

Springfield PA

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  • From: SE Minnesota
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Posted by jrbernier on Wednesday, November 2, 2011 9:56 PM

hoscale

Thanks for the advice.  Do these kits come with frog juicers? If not are they compatible with a comercial frog juicer like Fast Traks'  Hex frog juicer.

IIRC, Tam Valley Depot is who makes the 'frog juicer' for them...

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Thursday, November 3, 2011 7:02 AM

 Yes, the Frog Juicer sold by Fast Tracks is a Tam Valley product.

The only conenction between the servo circuit and the turnout is the mechanical connection of the servo to the throw rod so there is no issue of compatibility. They also have an accessory relay for the various servo controllers that can be used to switch frog polarity, cheaper than a frog juicer. Save the frog juicer for the manually operated turnouts, or crazy crossovers where it's next to impossible to figure out all the polarity combinations.

For the purposes of operating a turnout, even an all-rail (no hinge) type like those built with Fast Tracks jigs, a powerful servo is not required. Cheap 9G servos are plenty powerful for this purpose.

                    --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    December 2004
  • From: Pa.
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Posted by DigitalGriffin on Thursday, November 3, 2011 2:05 PM

Out of curiosity,

Wouldn't using a cheapo stationary reversing decoder attached to a tortoise do the same thing?  Just hook the frog to the switch pin of the tortoise.

That would come out cheaper than using a juicer.  The juicer looks nice, but I don't see the benefit for the cost.

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, November 3, 2011 8:06 PM

 Like I siad, in a simple turnout arrangment, some form of contacts to switch frog polairy is lots cheaper than a Frog Juicer, and really not hard to do. You have at least a 50/50 chance of getting it right, if the polarity is wrong and you short when hitting the frog, reverse the two track feeds to the contact. Done. But if you take a look at the trackwork on Tim Warris' CNJ Bronx Terminal, the insiration for Duncan developing the Hex Frog Juicer, you can see how trying to calculate which contacts on which Torotise to use when is NOT an easy job. Not only does the frog juicer save time (connect rail and and rail b, wire each frog to one of the outputs), it also saves a boatload of headaches trying to get complex crossovers working 100% with powered frogs.

 Like most electronic things, price per conenction drops when more are ganged - there is a Mono Frog Juicer for just one, but 6 of them far exceeds the cost of one Hex Frog Juicer. Granted, the Mono Juicer also handles more current so it can be used for a reverse loop controller or for a turntable.

                      --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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