Anna Hegedüs

I have a soldering iron.

Quasar XP1478BH with composite input

I found this adorable little guy in a junk pile in an abandoned house. He's CRT and neckboarda tiny black and white television set with an AM/FM radio built-in. If you like, you can run it off of batteries and it also has the option to fit some sort of battery pack, when you remove the spacers from the battery compartment itself. On the back, there are adjustments for contrast, brightness, and vertical hold, an input for an external antenna, and the socket for the AC adapter. The front folds closed and turns into a convenient carry handle and protector for the front panel. All in all, it's a sweet little relic from the past. Too bad it doesn't really...work.

NTSC broadcast television has not existed for quite some time in the United States. Due to the fact that this television receives over the air signals only, the TV could really only pick up static. Technically, you could find an external antenna adapter, plug it in, then use a digital converter to pick up HDTV signals. In fact, that is what I did here. But that's a bit cumbersome, isn't it? Not only that, but there are way better things to use a TV like this for...like Atari games!

After cracking the case open, I quickly discharged the tiny CRT with a screwdriver and a ground wire. I then removed the PCB and found the VIF and SIF demodulator. It is a sound and signal processor for the TV and basically takes what the RF modulator has, turning it into something that the TV can use. The one on this board is the AN5715K.

VIF/SIF

What you see here is a diagram and pinout of the IC. Pin 4 is audio output from the internal amp, and pin 14 is video output from the video amplifier. Theoretically, if I bypass this with a composite signal, I should be able to get a nice, clear picture on the tube of whatever I choose. Wiring a set of composite jacks to it would allow me to use whatever signal source I want to use. If I want to hook up a game console? Fine! If I want to use a converter box directly, without a modulator, also fine! The VIF/SIF is no longer necessary because we are injecting a signal directly that has no modulation. So with that in mind, I cut pin 9, then took my flat-tipped screwdriver, touching it to the trace leading to pin 14.

TV composite signalYes, that seemed to work. I then took an alligator clip, connected it to a hacked-off composite jack stuck into an HDTV tuner, and tried the audio. On pin 4, we had audio! After tapping ground off of a safe part of the board, I slowly put the unit back together, keeping a small hole in the underside for the composite leads to stick out. I then used some hot glude to secure them, and soldered the lines directly to the pins I had found previously. Everything worked great, and now, in addition to it working as a cute little AM/FM radio, it also has the ability to be a black and white monitor! For what, I don't know, but I'm sure that I will find a use for it sooner or later.

I was thinking that it would be a very cute idea if I were to take a Raspberry Pi and fit it into the battery compartment. With the addition of some Atari 2600 and NES emulators, I could have the heaviest, most awkward portable game console ever conceived, and it would be absolutely beautiful in every way. Another idea that I had was fitting a Google Chromecast into the battery compartment, along with an HDTV to composite adapter. If I am able to do that, I could turn it into a genuine streaming device, capable of displaying classy black and white movies in miniature. I could also use it as a portable radio.

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