Alesis ADAT HD24 Remote Control Pin Out

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.

Add a Fuse Holder to JBL EON Series (Gen 1)

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:

• Fuses & Fuse Holders This pack comes with a bunch of fuses. Use the 2A fuses.
• 16 AWG wire Only a few inches are needed.
• Step Drill Bits I used these to make a 1/2″/12mm hole for the fuse holder to fit through.