A 3-year journey of, erm, discovery!
Yes folks, it has actually taken me 3 years to repair this highly desirable CRT TV. It’s been a bit of a journey to say the least. From being scared stupid of even taking the back off one of these, to totally dismantling it.
About the Philips Discoverer TV
The Philips Discoverer TV is what happens when 1980s industrial design meets the space race and nobody in the room says “perhaps we should calm down a bit.” Released in 1983 and inspired by the excitement around the early NASA Space Shuttle program launches, Philips decided the best way to celebrate the future was to make a television that looks suspiciously like an astronaut’s helmet.
Behind the smoked visor and brightly coloured plastic is a completely ordinary analogue CRT with a tuner and RF input — which is exactly why it’s so good for retro gear. Feed it through an RF modulator and old consoles, computers, and VCRs look exactly as they should: soft, slightly fuzzy, and gloriously analogue. No scaling, no lag, no menus — just phosphor doing its thing.
Of course, being a forty-year-old CRT, it occasionally requires a little encouragement. A tweak here, a capacitor there, maybe the odd adjustment to remind it who’s in charge. But that’s half the fun. The Discoverer isn’t just a television — it’s a small plastic monument to the moment when the future involved space shuttles, bold design, and absolutely no concern about whether your TV looked like a helmet.
Did you buy a broken one?
Me? Buying broken things in order to fix them up and to avoid paying hugely inflated prices for them? Not this time, no.
I should have known though, it was a bit of a bargain at the time. But, it was collection only and literally around the corner from me.
What could possibly go wrong…?
Something went wrong
I was so enamoured with the Philips Discoverer TV that I completely and utterly forgot to ask the seller to switch it on so I could see it working!
I got it home and immediately plugged it in. Hooked a console up to it, and bam! It was all good and looking very lovely.
It didn’t last long though. As the days and weeks went on it became more and more temperamental. Refusing to switch on. I thought I’d found a sneaky workaround by putting it in to standby and then just unplugging it. Seemed to work for a while.
But soon, it just completely refused to switch on. Disaster!
Side Quest and a warning
⚠ CRT Safety Warning
CRT televisions are wonderfully repairable pieces of technology, but they come from an era when electronics cheerfully threw around voltages that modern gadgets wouldn’t dare. Inside a CRT set you’ll find circuits producing tens of thousands of volts, and the picture tube itself can hold a charge long after the plug has been pulled from the wall.
In other words, if you go poking around blindly, the TV may decide to teach you about electrical safety the memorable way.
That doesn’t mean they’re impossibly dangerous — thousands of people repair CRTs quite safely — but they do require a bit of knowledge and a lot of respect. Always unplug the set, allow time for things to settle, and learn how to safely discharge the tube before working near the anode connection. Work methodically, avoid touching anything you don’t understand, and remember that “it’s switched off” does not necessarily mean “it’s safe”.
Treat a CRT with the respect it deserves and it will reward you with a beautiful picture and decades more life. Treat it casually and, well… the lesson may be somewhat more immediate. ⚡
With all that in mind, before I started any work on my Philips Discoverer TV, I went on a mini side quest and made myself a little tool to discharge it. There are many guides online for making one – mine involved a large screwdriver, some cable, some insulation tape and a crocodile clip. Go and research it, build one, or buy one, and then come back here!
And so it begins…
I scoured the interwebs for what might be wrong. Initially, everything pointed to this inductor:
Looks dodgy if you ask me. So I ordered some new ones. Replaced it. Nothing changed. Long story short, a couple of months down the line I realised that (a) the seller had sent me the wrong component, and (b) the original inductor was absolutely fine.
Anyway, time for my favourite thing. A full re-cap. I always blame the capacitors, so that must be what’s wrong, right? Wrong!
How not to do a full re-cap
So. CRT TVs scare me. Or at least they did. All those thousands of volts milling around in the back of my Philips Discoverer TV made me supremely cautious. But not only that, I couldn’t work out how to get the main board free of the TV, so I just slid the board out as far as it would go and then set about removing and replacing each capacitor in turn.
Can you imagine it? It’s tethered to the TV by various cables and the flyback transformer is connected to the main tube. Not to mention that neck board in the middle of the image there. Trying to replace the capacitors was a nightmare – because I didn’t know any better!
After the re-cap, I turned the Philips Discoverer TV back on, and it was fine. I put it all back together and it was immediately not fine. It wouldn’t turn on again.
I gave up. And over the course of nearly 3 years I revisited it from time to time. Desperately testing and replacing various components.
Eventually it started displaying a new problem, not only would it not turn on, but it started to make a really really, oh my God it’s going to blow up, loud buzzing noise from the speaker. This scared me even more!
The Flyback Transformer
This is the beast that generates all those thousands of volts and is connected to the TV tube with and has a rubber cap over it. That’s the end you use the discharge tool with.
All my research, all my conversations with various AI models, I finally came to the conclusion the Flyback Transformer needed replacing.
Of course, the only one I could get my hands on was in Australia, so I had to wait what seemed like ages for it to arrive.
In the meantime, I had to be brave and completely dismantle the Philips Discoverer TV. This meant pulling back the rubber cap and removing the metal inserts from the tube. After discharging the TV of course!
It was actually pretty easy. Then I removed the neck board, which also turned out to be really easy, and set about de-soldering the Flyback Transformer from the main board and the neck board.
Psst! Wanna see a naked Philips Discoverer TV? Of course you do!
Did it work?
Of course it… didn’t! No change.
What the heck do I do now? My lovely Philips Discoverer TV. Look at all those people on Twitter (no I will never call it X), and Bluesky and everywhere else with their lovely working ones.
Back to the AI, and suddenly a clue. In all the millions of things it suggested, including many capacitors that didn’t exist on the board at all – some great hallucinating there – was a throw-away comment about the audio chip.
Okay, how do I test if it’s that?
“Oh, just lift the leg of the chip where the power is coming in.”
Oh really? That simple eh? Nope. The chip is soldered to the board. How am I supposed to lift just one leg of it clear?!!
Back to the AI (what did we do before AI?!) and time for some deep research. How do I temporarily cut the power to the Philips Discoverer TV TDA7052 audio chip?
After a while, I got my answer, lift one leg of the resistor, R3100 (not pictured). Now, that I can manage!
So did it work this time?
Yes. Yes. Yes! YES! Power! Fuzzy screen. Turns on. Turns off. Turns back on again. Joy! A fully working Philips Discoverer TV!
Now let’s connect something to it, adjust the new Flyback Transformer settings and make it look lovely.
Oh…
Are you kidding me?!!!
Nope. The horizontal wobble effect was truly awful, especially towards the top of the screen. Now what?
Colours? Good. Sharpness? Good. Wobbliness? Not good.
Will you please fix your Philips Discoverer CRT TV?!
I’m trying okay? While I waited for a replacement sound chip to arrive (by the way I soldered a socket in to make future replacements easier), I set about checking the capacitors again. Had I done anything wrong?
Why yes as a matter of fact I had. This goes back to when I couldn’t work out how to remove the board completely. So I was basically working back to front on it. I discovered that I’d got two capacitors on the left and right of the board completely swapped round!
I sorted those out and still everything was wobbly.
So what was doing it? Even the TV’s on screen menu was wobbly.
I decided it must be something near the RF modulator, maybe near the audio chip too. I settled upon capacitor C2054.
Yes, that’s the same image as before, but you can see C2054 immediately to the right of the audio chip. Looking underneath, something seemed odd where one leg was soldered to the board.
I very helpfully didn’t photograph that, sorry. But, when I removed the solder, it turned out that the pad where one leg was soldered in place had completely lifted from the board. Could this be the problem? I decided it wouldn’t be the problem, but I sorted it anyway. I traced from that pad to a nearby place on the board where I could patch a wire between there and the capacitor’s leg.
Finally?
3 years.
3 years from being scared to take the back off the Philips Discoverer TV, to being able to dismantle it entirely.
3 years of replacing everything in site because I didn’t know what I was doing. But I’ve learned a hell of a lot.
3 years to get to this:
Whoop whoop whoop!
What an epic journey! I finally have a fully working Philips Discoverer CRT TV and I’ve been using it every day since!
I’ve hooked up the Atari 800XL and played Dropzone. I’ve connected the Philips CDi and watched Star Trek II: The Wrath of Khan. I’ve plugged in the ZX81 and got a lovely flashing “K” on the screen. For extra fun I got an HDMI to RCA convertor, connected that to the TV via my VCR, and had RetroPie running various arcade games – and even watched YouTube on my Firestick – because, why not?!
It’s not perfect, I can see a couple of large rectangular light areas on the screen – more noticeable when there’s a plain background. And I can’t seem to get the horizontal centring to work correctly, but it’s my very own Philips Discoverer TV and I love it!
