Backlighting on the PM.

[Carl Watts]

I have some LED's designed to backlight and it could be done on the PM4 and PM4 however the main problem is that you still need to drive quite a few LEDS and the current is getting to high so you would have to power them from the USB power supply. This then generates another problem for some people in that you need a USB cable and PC or at least a USB adapter plug pack into the mains. The LEDS go down the side of the glass and point inwards. Have not got round to trying it as there are always more important things to repair or do.

[Hollywood_Kuma]

Hi Carl,

Thanks for this. I've also considered putting a string of LEDs on either side of the monitor, but faced exactly this problem - that of providing the power. Where I row, on the roof of my apartment building in LA, there is no power, so if I was to go down this route I'd have to either bring my PC onto the roof as well, which is a pain, or buy a USB charger/backup unit, which would also be an annoyance and an expense.

What we really need is a backlight that takes its power directly from the battery pack, which shouldn't be a problem for the PM4 as the current generated by rowing ought to be quite substantial, and the battery pack is pretty chunky. After all, I get a lot of "light on" time from my iPhone's screen, which is powered by a much less substantial battery than that which goes into the back of the PM4.

I think what we need is something like this, although it would need the C2 guys to co-ordinate a solution in order to get something that worked OK:

http://tlcom.manufacturer.globalsources ... klight.htm

C2 say that they have some prototypes, so I'm hoping that they will decide to move them into production.

[Bob S.]

I have some LED's designed to backlight and it could be done on the PM4 and PM4 however the main problem is that you still need to drive quite a few LEDS and the current is getting to high so you would have to power them from the USB power supply. This then generates another problem for some people in that you need a USB cable and PC or at least a USB adapter plug pack into the mains. The LEDS go down the side of the glass and point inwards. Have not got round to trying it as there are always more important things to repair or do.

Weird timing! Just last night I was wondering whether or not the monitor could be powered with the USB cord and an adapter. Now I am delighted to see that the answer, right here in my morning email, is yes.

The other item I was wondering about at the same time was whether or not use of the USB cord and adapter would override the automatic 4' shut off. As it is now, if I start a very long piece and think that I might have to take a break longer than 4' (away from the erg) I have to hook it up to the computer. It would be handy if it could be done with a simple adapter instead of a whole computer. Would that work? It would be a convenient option.

Bob S.

[Citroen]

There's no problem running it from a cellphone charger (you'll get way more amps than you need since they're usually rated at 1000mA and the PM3 only needs 100mA).

[Hollywood_Kuma]

The 4 minute power off is rather aggressive, and I wish C2 would make this longer (say 10 minutes) in the next firmware release. The battery pack on the PM4 is pretty chunky, so it wouldn't be an issue and would stop the annoying premature shutdowns when you're rowing with a rest interval.

If you add a USB power source, however, the screen stays on indefinitely. But it's a pain, it's more cable, and I don't have power where I row on the roof of my apartment complex.

As a simple, crude stop-gap, if you simply pulse the "change units" button four times, it will reset the shutdown clock without resetting any data, so you'll get another four minutes grace without losing data.

Hope that helps.

[Carl Watts]

The LEDS I was refering to are to be fitted internal on the monitor, like a true backlight set-up.

USB from the PC can supply about 500mA so no problem with power. Just has never got to the top of the priority list as only on a couple of occasions I have started to row and forgotton to turn the lights on in the room and had to fininsh rowing in poor lighting where the display was not clearly visible.

The lastest version of Firmware has the monitor turn off in like 30 seconds from the main menu if no buttons or rowing is detected.

[Hollywood_Kuma]

Hi Carl,

It would be really cool if you could work out a way to get the LEDs inside the PM4 case, to give a backlit effect. I took my PM4 apart to see if I thought I could do it, but it's fairly tight in there. If you were looking at a string of LEDs, however, then I guess there might just about be room for that. If you do get the time to do this, and you can post an idiot-resistant, if not idiot-proof guide, then I know there would be many us who would be very grateful.

Given the length of time this thread has been open, I think we will see China land a man on the moon, Americans pay off the national debt, Jews and Arabs make peace, Russians embrace gay rights, and the world complete nuclear disarmament before C2 put a backlight in their monitors. It's a shame, because even the manufacturers of the cheapest and nastiest C2 copies seem able to make this technological leap.

I've finally found a reasonable work-around, which might also be useful for others. I am now using the C2 phone holder that sits atop the PM4 monitor (which C2 sells for $5) together with a Mighty Bright HammerHead LED music book light, model 54810 ($17 on Amazon). The Mighty Bright is designed for musicians to illuminate sheet music during a concert, but it works really well on the C2. The battery case, fortuitously, is the perfect width to fit snugly and securely into the C2 phone holder, which then holds it in place in a rock solid manner (unlike e-reader lights which I've found can fall off during an intense rowing session). Also, the light is nicely bright, and because it uses six LEDs, the light is diffused over the entire screen, rather than concentrated on a particular spot. The width of the light head is three inches, which is exactly the same measurement as for the square sides of the PM4 display, which is why it works so well. The light runs off three AAA batteries, so there are no issues in terms of USB power.

Of course, a backlight would still be the perfect solution but, as this does not appear to be coming any time soon, the Mighty Bright (plus C2 phone holder) seems to be a very good workable solution in the interim. I've posted a some images below.

PM4 illuminated

C2 Light 2.JPG (59.83 KiB) Viewed 9874 times

The Might Bright, how it's fixed (front and rear views), and three inch light head, containing six LEDs

C2 Light Composite.jpg (59.57 KiB) Viewed 9874 times

[Carl Watts]

There is room between the sides of the LCD and the case on the inside. The LED's I have are rectangle and have two LEDS per package. You simply would have to clear silicone a string of them down each side of the LCD. The wiring would be messy but its out of sight. I may give it a try as soon as I get time.

PS the Chinese are going to be the FIRST to put a man on the moon. I really hope it create s a space race for real this time. Sorry but the rest is never going to happen.

[Hollywood_Kuma]

After almost eight years since this thread was started ... the PM5 with backlight is released.