Double up, another use for a Y-harness!

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Folks often don't realize the stock JR-type radio connector is only rated at 5A. While this was plenty back in the day when servos drew 150mA or maybe 250mA for a big hairy servo, fast forward 30 years and nowadays, they're not really up to the job except with small toy-like models because a single servo - all by itself - may require 5A, or more!

Meanwhile, modelers hoping radio system manufacturers will put their heads together on a solution better not be holding their breath because competitive market pressures still see them doing what they can to fragment the market and seeking advantage at the expense of others. This, versus developing standards everybody would benefit from.

In the meantime, we at ProModeler work to offer innovative ways to bring additional juice into your model's receiver using the tools at hand. How? We show you how to double up where possible. How? By using batteries or BEC with multiple discharge connectors plus, when you're out of available channels, an ordinary Y-harness!

- This sweet looking ProModeler Y-harness is molded to reduce the rat's nest

ProModeler was first to offer battery packs with two leads.This was back in 1983. This innovation remains popular with prudent modelers who continue to recognize the risk to their model of relying on a single radio on-off switch.

Basically, running two switches in parallel reduces risk because odds of both switches failing on a single flight are astronomical. Others have begun copying us and honestly, we don't mind!

The point being, if you opt for a cheapo pack from someone else, that's fine by us because we'd rather see everybody enjoying the sport more safely. However, the fact we introduced it first doesn't mean we're standing still.

- An XT30 connector increases the versatility of the popular B2S2000-10C

So while our twin-lead batteries remain a top selling product amongst the most savvy of modelers worldwide, we've begun adding a third discharge connector to the mix. And instead of opting for a proprietary solution, we went to the open market for the nifty Amass XT30 (the 30 meaning it's capable of handling 30A). People use these everywhere, even for connecting high power speaker systems!

Meanwhile, back in the day our purpose was to permit using two switches to avoid the single-point of failure that could trash your model in a crash. These days, two leads gives you another important benefit. Basically, two leads, each rated at 5A allow you to deliver 10A of current to the receiver. And as it turns out, 10A is enough for virtually all models - sweet!

Why is this important? It's because even a small 3D model aircraft equipped with four of our DS75CLHV sub-micro servos can push the current handling capability of a single JR-type connector. And if you drive a heavy powerful rig like a TRX4 or an X-MAXX four wheel drive truck, then the single steering servo alone can push that JR-type connector!

And herein lies an issue, especially for folks driving those über popular trucks, the receiver may not have an open port where you can add a second power lead. Fortunately, the nifty little Y-harness - most often used to drive two servos with one channel - comes to the rescue. And the best part is it qualifies as a low-buck solution to your problem!

- Connecting a Y-harness to the receiver lets you hook up battery and servo!


This Y-harness trick works in reverse because a radio receiver (if you pull it out of the plastic case and look) demonstrates a perfect example of a bus for powering the servos. This just means the signal-pins (S) are isolated from each other while the (-) pins are interconnected and the (+) pins are interconnected. Using even with a cheapo volt-Ohm-meter let's you prove this for yourself. Let's see how!

As usual, the first thing you do when using an Ohm-meter is to touch the probes to each other and confirm you see 0O, or a short circuit. And if you'll allow me a brief birdwalk, O is the Greek symbol Omega, and it stands for resistance. Resistance is measured in Ohms and the Greek symbol for Omega (O) is used for the SI-derived unit of electrical resistance (named after German physicist Georg Ohm). Now back our lesson for the day!

- If you're a lifer, it pays to invest in good tool like a good volt-Ohm-meter

Meanwhile, it you check connectivity the signal pins of the receiver, you're going to find an open loop between each. This means they do not connect to each other - ever! And when you look at your meter, the reading will indicate an open circuit usually as OL for (Open Loop), or perhaps infinity (8) on some meters. Both mean the same thing, no connection!

- OL means Open Loop and this means there's no interconnection - none!

Earlier I mentioned the (+) pins are interconnected as are the (-), which interconnect to each other as well [but the (+) and the (-) are isolated from each other, of course, else everything goes up in smoke]. In this instance, when you touch the probes of your meter to either two (+) pins or two (-) pins, you get connectivity, or 0 Ohms of resistance.

On this receiver I'm measuring between any two (+) pins and I see 0O. This means a perfect short circuit, or meaning that the two pins are connected somewhere. The 'somewhere' doesn't really matter. The fact is they are interconnected. Ditto the (-) pins.

- Connect any two (+) pins and seeing 0O proves there is connectivity of all

Anyway, the point of all this is, you don't have to connect the battery to where it's silk-screen (or otherwise marked) BATT for battery, but can instead connect it anywhere you have a free channel port - nice, eh?

What's this mean? Well, as a practical matter it means you can use a Y-harness to deliver juice 'to' your receiver if all the channels are filled (or assigned) by servos. This, versus using it just to connect two servos to one channel of your receiver.

Bottom line? Becoming a professional modeler merely involves thinking in the way of the pros . . . so that you're always thinking outside of the box!

- Avoiding limits set by others is all in the mindset - it's the ProModeler way!

So if you want to use a better battery (one, by definition equipped with more than one lead for added versatility), and your receiver's channels are all full, then the trick of using a Y-harness in the reverse direction is an easy way to go about it.

Basically, you just connect your Y-harness to any occupied channel of the receiver (e.g. where there's a servo already connected), and at the other end, connect both a battery lead and the same servo. Voltage flows to the power bus from the battery and is also drawn by the servo at the same time. Win-win and as usual with ProModeler, we try to make things easy-peasy!

- Easily connect a battery lead and a servo to any channel of your receiver!

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