Oh, I have such a love-hate relationship with some manufacturers.
Now… I had previously made a vague shitpost while working on a Harris Apex A2X exciter. This would have dated back to, well, when they were Harris Broadcast before the spinoff that left them independent as GatesAir, with another division becoming Imagine Communications
Imagine Communications…. Because they aren’t necessarily ever going to work outside of your vivid imagination
Anyway let’s just get right into YELLING IN BROADCAST ENGINEER. First stop: The Apex M2X oscillator board.
Frequency stability is vital to generating a good solid digital TV broadcast signal. The Apex M2X features a disciplined OCXO (Oven Controlled Crystal Oscillator) with several options as to how to ensure proper longterm calibration – it has a GPS receiver, 10 Mhz external reference, and 1 PPS external reference options provided. More on OCXO references here (this describing a more basic, free-running one, without sync inputs). However, the OCXO itself is, uhhhhhhhhhhhh
WHAT DID YOU DO HERE
WHAT IS THIS
WHAT IS ANY OF THIS
YOU GUYS JUST GLUED A BLOB OF PACKING FOAM OVER THE OSCILLATOR AND A LINEAR VOLTAGE REGULATOR WHY DID YOU DO THIS
LOOK AT THAT BULGING CAPACITOR OF HAPPINESS ALL UP IN THERE OH BABY
I wanted to peel this crap off but I was fairly confident that if this is anything like the antistatic foam that ICs used to come packed in, it may have broken down and corroded parts under it and I’d be faced with irreplaceable parts that went out of availability two years before they sold this exciter crumbling to dust. So I left it alone. It only has to last about another year, if even that. I hope. Did I mention HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH? Because HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
So. Let’s move on to the power side.
The power supply is along the left wall of the exciter. On GatesAir’s admission, the power supply pretty much expires and becomes a ticking time bomb after 5 years – power it off and it will never ever start back up again.
But that’s unrelated to, uhhhhh, The Internal UPS Thing Of WEIRDNESS
For unknown reasons they felt the need to give the unit battery backup. It does not fully power it, like, the RF output disappears once it’s on battery. I think all it does is keep the controller with the RTAC data* in memory alive, and keep it from having to entirely run through the several minutes long boot process following a momentary power glitch.
It is, however, FUCKING RIDICULOUS.
On later versions it uses a lithium ion battery which consists of three 18650 cells, but rated at only 1.5 amp hour, which suggests… some 18650s of hilariously low quality. Behind the board is a charging / BMS circuit that steps the battery voltage up to 12V to keep the exciter powered. On earlier versions, they went through all the trouble of building this elaborate charger/step-up board, similarly…..
And then, waaaait for it—–
Ok, take a good look at this, and prepare yourself for the description of what you’re actually looking at: someone… went through the trouble of getting a spot welder in house and welding tabs to unmatched dumpshit tier** Energizer retail packed NiMH cells.
Because, uh, only the finest with Brand HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH.
There is another memory backup battery, but I’m guessing that’s mostly just for the realtime clock.
* Sorry, I am not currently in a sufficiently coherent mental state to describe what RTAC does, other than that it is Fucking Magic and if the Fucking Magic doesn’t work, the signal comes out on air as distorted non-decodable dog turd
** only slightly better than Duracell