Large Scale Central

New Airwire G4 Decoder information.

I just noticed today that information on the new G4 decoder that they were showing at the national convention has been posted on the CVP website. I don’t know if dealers have them yet or not.

http://www.cvpusa.com/airwire_g4x.php

Pretty cool. The DCC output is rated 3 amps, so you could probably drive a small DCC decoder with sound, as opposed to sound only.

Why would I mention this? Because you could add an HO Zimo decoder for example, get the sound, but also a couple of servo outputs for animation, or if you wanted servo driven couplers (the Phoenix ones are solenoid).

(yes you could use the Phoenix coupler driver board that can drive solenoids or servos, but it costs $70 street price, almost as much as a Zimo MX645 or similar which gives you sound and servo and more)

Sounds like a big step forwards. Please keep us informed on your opinion on performance, especially the improved motor control.

Greg

Greg, does the Zimo have better sound and is it compatible with all

the larger parts a g scale would need? Asking because I have no clue on electronics and what is or isn’t needed

Greg, does the Zimo have better sound and is it compatible with all

the larger parts a g scale would need? Asking because I have no clue on electronics and what is or isn’t needed

Well, they have increased their US library and it’s pretty robust.

In terms of sound, the sound is very good, plenty of power in the amps, sychronized chuff and ability to pulse smoke units, and built in servo control.

They make a very wide range of decoders, but in this specific case as an alternative to the Phoenix, and still having the G4 run the motor. The example was adding servo control inexpensively, for servo controlled couplers or other animation.

You might go to the zimo site and see the wide range of decoders available. Other than the QSI units I use mostly, it’s my go-to decoder.

So, again, I was talking a specific case here, in combination with a G4 airwire, the topic Paul started.

Greg

I work with Trainli and use the Zimo decoders. The MX645P22 at $100 has the following features:

Sound programmable decoder with 3 watt audio, 1.8 total amps (2.5 amp peak), 30 volts with 50 volt peak, 2 servo or susi, full control of light outputs, capable of programming drive for fan driven smoke units like Aristo/USA Train, trainli units, and the ability of programming a servo for the waltz on uncoupling (at a single push of a button, the engine changes direction, opens the coupler and then pulls forward away from the rolling stock.

Note the large scale decoders (MX69x) have 6 amps and 10 watt audio, 4 servos and all the other MX645 features.

Do note that Zimo like Phoenix has free sound projects, but there are some non-Zimo personal that write their own sound projects and charge a fee for an activation code and for the MX645 it is $25 at this time, and $35 for the MX69X series decoders. All Zimo sound decoders have unique serial numbers for this purpose.

Forgot to mention that the Zimo decoders will operate the Kadee uncouplers directly from the servo control pins on the decoders, no need for a separate Phoenix transmitter on engines.

Yes Dan, ha ha, that was my major point in my first comment, you get servo control basically for free as compared to other sound board options, or the extra cost of a phoenix coupler controller.

Of course if you use solenoid type couplers, the G4 has the driver on it already.

Greg

Are they going to work the G4 into their Drop-ins?

Paul: Have you installed a G4x board yet? Just a week before the Portland convention, I had my first Airwire Drop-in board (with a Phoenix P8) installed in one of my GP9’s. Now I see that this new G4x was promoted by CVP at the convention and released soon after and it’s making me have second thoughts. I always like to have the latest o’ the greatest and consistency with electronics in my locos. Other than the integrated Phoenix coupler driver circuitry/drivers, “improved motor control and protection”, and a better smoke driver, I don’t see any dramatic differences between the two. I don’t need the Phoenix couplers, and I don’t do smoke anyway as it drains the battery faster. I already seem to have good precision motor control with the Drop-in board, so is the biggest advantage here the “cruise control”? I also wonder about any improvement on its transmitting distance.

Michael,

I don’t have one yet. I think we will just need to wait and see what the reviews are like.

I don’t have any new locos, so it would need to be a retrofit for me at this point just to see how it works. Not sure I want to do that kind of expense.

Hey guys, I’m looking to buy a couple of these once RLD has them in stock. I’ve been using the original AW900 for what must be15 years now. I have a GP7 that’s been having trouble with overheating, so that’ll be the 1st on the list to be retrofitted. Looking forward to having the lighting options and quiet motors!

The output power rating to the motor does not seem to be changed/increased.

it’s 120 watts, not a flat 10 amps as the rating is sometimes misunderstood. If you are overheating the motor driver portion, the signs point to no improvement in power over the older units.

Trying to read between the lines, though, they mention they can take surge currents of 55 amps, so perhaps they have improved their mosfet drivers.

at 18v, you have 6.66 amps for 120 watts… it takes a bit of work to make even a USAT geep draw that much continuously. Have you ever measured the amp draw on your overheating loco?

Greg

Hi Greg,

No issues with the GP…everything tests out nicely. Problem only happens at low speed with a sizable load. I think the speed controler is just out of steam. I run 14.4v so that would give me 8.3amps. The functionality is really only a half of the reason for swapping out though. LED drivers and quiet motor drivers are the biggest attractions to replace at this time.

Roccky,

There is a huge difference in the motor control on the first two generation decoders and the G2,G3 and now the G4. There is a very noticeable hum in the first two generation decoders. That is gone with the G2 and G3 with much better control. And now the G4 has improved on that according to the literature.

Some of the early PWM frequencies were very low, clearly in the audible spectrum, same happened with early Aristo controls.

For the overheating GP, perhaps a small fan blowing across the output transistors would help. While the system might be advertised as capable of 120 watts, there is no way that the board can continuously dissipate 120 watts, there’s just not enough radiating surface. A small fan will probably make a world of difference, just breaking up the boundary layer alone.

Greg

Rocky Canyonero said:

Hi Greg,

The functionality is really only a half of the reason for swapping out though. LED drivers and quiet motor drivers are the biggest attractions to replace at this time.

I just had a GP9 Drop-in board installed with a Phoenix P8. The motors are quiet. The installer (who has done quite a few battery installs for the BAGRS club) left all of the incandescent bulbs, including the headlights, number boards, and cab light, in the engine. The smoke function is turned off. The Tenergy battery (which is a used one) drains prematurely. The other day, I let the engine sit idle on the track with the lights and sound on, no motors running, and after 45 minutes the loco went dead. I know the LED’s are much brighter and you can see them more clearly in daylight; I’m just wondering how much more current the stock incandescent bulbs are drawing compared to what the LED’s would draw. Unless I’m wrong, it doesn’t seem that the incandescent bulbs, which are continually lit while running, are a big factor in reducing battery life(?). Anyway, time to replace the battery I guess…

Don’t want to derail this thread about the new Airwire G4x board. My installer has the new G4 board in stock and he says the predominant change from the G3x and Drop-ins is support for the Phoenix electric coupler. The screw terminals for hooking up lights has been changed to plugs and ribbon cables, which he thinks is undesirable. The G4 obviously has more power capability, but that’s minor as the engines don’t need the extra amp capacity.

Incandescents, depending on type, can draw 100 milliamps or more. LEDs typically draw 20-30 milliamps .

I was thinking along the lines of what Greg was saying. The board maybe overheating because the air around it isn’t moving. That is why power transistors and drivers are in vented cases, sometimes with heat sinks on them, and in some cases with fans blowing on them. A small CPU type fan might solve the problem.

Not a fan of plugs for lights on LS decoders. Very not a fan of ribbon cables, can be a real pain if you need to re-use or re-wire and you don’t have another ribbon cable.

The load of lights on the circuit in USA trains diesels is high, I got around 300 ma for the number boards, the headlights and the classification lights AT the lamps themselves (class lights are leds).

Now these were powered from inefficient series pass regulators and I did not include the cab lamp either.

At the bottom of this page I put the actual measurements before conversion (go to the bottom) https://elmassian.com/index.php/large-scale-train-main-page/motive-power-mods-aamp-tips/usat-motive-power/f3/f3-dcc-install

So getting to over 1/2 amp is possible it seems to take an overall guess. If all the lamps were left, were all the regulators too? Was the main board powered directly from the battery, so all the existing regulators were used?

Greg