If, like me, you're of a certain age and grew up in the American educational system, you'll probably recognize this beast: A Califone 1403k "stereo compatible" portable phonograph.
Built from the 1960s until the early 1990s, this massive beast was the joy of every elementary school age kid in the US and Canada who wanted a chance to get away from spelling and arithmetic to listen to the dulcet tones of The Letter People.
While audiophiles may look at this thing and cringe, I actually love this particular unit for several reasons: First, it has a lovely retro aesthetic--beige with a dark leather veneer--that just screams late 70s/early 80s (yeah, I'm one of those weird kids that appreciates that ugly brown 70s look). It can also play just about any piece of vinyl that you throw at it--from a 78 all the way up to 16RPM (it also has a really cool built-in adapter which is extremely convenient for 7" singles).
Now, besides just looking cool and being able to play anything you put on it, this thing is extremely cool because it was designed for the educational market meaning that it has ultra-solid construction: the Califone record players are built of steel and lumber, making them heavy and virtually bulletproof. The 1400 series was designed for kindergartners to climb on or throw across a classroom and keep working--you'll never see that kind of build quality from consumer electronics again! Of course, the downside to being designed for educational use is that it is built to a price. Califone was never known for their sound quality, and the 1430k is not the most high-end, high-fidelity vinyl playback system that you'll find. It is monaural, and it does have a pretty heavy tracking weight that can prematurely wear out some records, but it's not a bad sound and it is entirely adequate for playing the occasional vinyl records at home. Would I use it as a daily driver for most of my listening? No. I also don't use a Commodore 64 as my main computer, but I enjoy working with it for historical interest and as a hobby. In the same spirit, I want to give this unit a much-needed renovation while respecting its unique history and aesthetic.
The Califone 1430k isn't a terribly complex piece of equipment: apart from the AC transformer and speaker driver fastened to the steel chassis, a 3x5-inch PCB holds the entirety of the solid state circuitry. My goal will be to replace the existing board with one of my own design that incorporates a small stereo pre-amplifier with the existing single-knob tone control, a class D main stereo amplifier, and a new, simpler power supply. Of course, for true stereo sound, I'll need to replace the entire tone arm assembly starting with the cartridge and stylus, then run new wiring down to the amplifier board.
Sourcing a new stereo cartridge that fits inside the existing tone arm is going to be tricky, but the Pfanstiehl P-228D looks like nearly a drop-in replacement for the Astatic 89T as it has the double-sided stylus and the footprint--as best I can tell--matches that of the mounting holes on the Califone tone arm! From there, it's just a matter of designing the amplifier circuits, cutting a board, and assembling.
I haven't decided if I want to go any further, but I'm tempted to see if I can update the auxiliary output options on the Califone. Bluetooth would be nice, but the steel chassis may prove too problematic. I've also considered adding line-level output in the form of stereo RCA ports or even TOSLINK (because I'm a masochist), but that would require cutting the original case and I'm not convinced that I want to even attempt that! I'll keep my options open, though, and we'll see where this journey leads me.