Here are the measured resistance values for each button press on the remote control.
The remote control for the Alesis ADAT HD24 recorder uses combinations of 1/8 watt ±5% resistors to alter an input voltage.
I don’t have access to the recorder unit. Based on what I see inside the remote control I’m assuming it determines which button is pressed by measuring the voltage that is returned. Each button would lower the voltage by a different amount, thus making the measured value for each button press unique and identifiable.
The supply voltage that the recorder sends to the remote is unknown to me, but is likely one of the modern standard rail voltages — 3.3V, 5V, or 12V.
To obtain the following values I connected a digital multimeter across the tip and sleeve of the 1/4″ cable attached to the remote. All measurements are in Ohms.
Interestingly, the switch labels on the PCB differ slightly from the button labels on the case.
Also, I know this technically isn’t a pin out.
||Measured Value (Ω)
||(value read with no buttons pressed)
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Here’s how to modify first generation JBL EON series powered speakers to have an external fuse.
JBL EON10 power section with panel mount fuse holder added
The original JBL EON series powered speakers have a habit of blowing fuses more often than they should. Simply flipping the power switch could sometimes be enough to trip the fuse, rendering the speaker unusable until the proper T2A 250V 5x20mm fuse could be replaced. I’m sure that this design flaw was addressed in the much better EON G2 series, because I’ve never had the same problem with them (I’ve owned and extensively used both generations).
When a fuse does blow, fixing it requires removal of 14 screws to open the exterior, plus removal of 2 more screws holding the power PCB to the chassis. Then it’s a simple matter of swapping out the fuse and reassembling everything, which is complicated by having to make sure that the rubber gasket that seals the back and front enclosures together is properly lined up. All in all, it takes the better part of an hour to repair. That’s not very fun when you’re setting up for a show.
To shorten the diagnosis and repair time of a blown fuse, I added an externally accessible panel mount fuse holder. Luckily, the speakers have a convenient spot for just such a modification right next to the power switch. Here’s a photo showing what I did.
The pink lines indicate where the wires should be soldered up.
The parts you’ll need can be purchased via these Amazon affiliate links:
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Sometimes the solution is easy. Maybe the wires are just crossed.
A while ago I picked up a set of RGB LED par can lights from a friend. They are unbranded, but I did a little searching online. Turns out they are sold under the brand TMS, which I think stands for T-Motorsports, but can’t be certain.
They are just generic, low-cost lights that you can buy in packs of 20, 10, 8, 4, 2, and even 1. They’re super-affordable, small, and get the job done.
I haven’t really used them yet. In some recent tests I noticed one of the fixtures did not seem to be addressed the same as all of the others.
BEFORE: The can lit green should be lit red like the rest of them.
After confirming that the problem was that the red and green channels were flipped, I figured it was a problem that could be fixed easily. I opened up a good light and a bad light to compare the wiring.
On the left is a properly functioning can light. On the right is the can light with the red and green channels switched.
It might be hard to see in the picture above, but the blue and black wires coming from the control PCB were soldered to the LED PCB backwards at the factory. I fired up the soldering iron and swapped the connections.
Shown above are the black and blue wires before and after the switch.
Here are the all the lights functioning as expected after switching the wires.
AFTER: All 10 cans working properly.
So, yes, you get what you pay for. Cheap, unbranded lights might not be wired correctly at the factory. But sometimes good enough is good enough and a little know-how can keep the show on the road.
WARNING: Always be careful working on electronics. Unplug the power before opening things up. Don’t touch stuff on the inside. Be very cautious. You can be killed or seriously injured if you don’t know what you are doing. Prior to any electrical work consult with your local electrician, doctor, lawyer, and priest.
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