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Universal Mono Frog Juicer - Automatic Frog Polarity Switcher


24 In Stock

Additional Stock: 3 to 5 days

We can ship the MFJ001U immediately. If you order more than what we have available, we will hold your order until we have enough stock to ship your complete order.

PRICE : $16.49

24 in stock

The Mono Frog Juicer automatically and instantly switches the polarity of a single frog as the engine passes over the turnout. No more complicated wiring or electro-mechanical switches are needed. Instead, you connect power to the Frog Juicer and a single wire to the frog, and the Frog Juicer takes care of the rest!

The New Universal Mono Frog Juicer works with all DCC systems, including NCE PowerCab!

Need to switch multiple frogs? Check out the Universal Dual Frog Juicer or Universal Hex Frog Juicer!

Mono Frog Juicers automatically control the polarity of a single isolated frog in DCC powered trackwork. These units are ideal for automating single turnouts and wyes. Multiple units can be used to automate pieces of trackwork with multiple isolated frogs, such as double slip switches, three-ways, double crossovers, and crossings.

  • Eliminates the need for mechanical switches to switch the frog polarity when the turnout is switched
  • Instant switching means no interruption to the engine or loss of sound
  • Significantly simplifies frog wiring - especially for crossings and double crossovers
  • Compatible with any DCC system (It will not work with DC)
  • Simple to connect
  • An economical alternative to using a Hex Frog Juicer if only a single frog needs to be controlled.
  • Can be installed close to the controlled trackwork - no need for long feeders.

If you have ever struggled wiring up the frogs on a switch, seriously, you will want to consider using the Mono Frog Juicer. It is simple to use and just plain works.

How The Mono Frog Juicer Works

The Mono Frog Juicer consists of a microprocessor controlled SPDT electronic switch. This switch can sense and control the polarity of an isolated DCC controlled frog. When the circuit detects a short greater than about 1.7 amps (plus/minus 10% with two amps as the upper limit), it instantly switches the polarity of the frog. Two amps are below the reverse polarity detection point for most DCC circuit breakers and booster units, so the Frog Juicer will react before a fault is detected.

In addition, the Frog Juicer switches so quickly that the brief current pulse will go unnoticed by the DCC system.

Two amps are also enough current to power a single locomotive, and since only one locomotive can be on a frog at a time, it is all the power you need. The frog needs to be electrically isolated and have no other connections to the track or DCC system.

Frog Juicer Dimensional Drawing

6 reviews for Universal Mono Frog Juicer - Automatic Frog Polarity Switcher

  1. 3 out of 5

    Stewart Clark (verified owner)

    A reduced overall rating here due to a Canadian business that doesn't have an option to show pricing in Canadian currency. Very disappointed in that. Beyond that though great service from order placement to delivery and appreciate the step by step update of the order status.

  2. 5 out of 5

    Rick Wagner (verified owner)

    Don't know if Frog J is faster than a circuit breaker or trips at a lower current or both... but so far, works just fine on the down stream side of the CB. Good job guys.

  3. 5 out of 5

    James Petropoulos (verified owner)

    I find these little Frog Juicers quite handy! Seeing as I have crammed over 30 turnouts and half a dozen crossings on a 4X8 layout (modeling NYC industrial lines/LIRR), these Frog Juicers save a LOT of wiring because they can be situated close to the turnouts (or wherever convenient, such as on/under a control panel) and power can come from the nearest feeders. They have proven reliable and whether a single juicer or a hex juicer, they will make life a LOT easier if you don't fancy sending more than two wires to each switch machine!

  4. 5 out of 5

    Nick Vanwyngaarden (verified owner)

    Great service fast delivery and the product works exactly as advertised

  5. 5 out of 5

    James Yaworsky (verified owner)

    I have used these on my layout now for well over 10 years. They have worked 100% reliably and I've even used them for not just frog polarity, but on temporary reversing sections of trackage - they work great for that purpose as well. Needed more, so didn't hesitate to put in a new order now, which was filled very fast and professionally. Again, 100% reliable, and very easy to install - saves wire and a lot of fooling around.

  6. 5 out of 5

    Richard Marcinkowski (verified owner)

    Love these products, so simple to install and so dependable! Always work as intended.

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