My newest stupid project...

I've written and posted videos here about my much-beloved JVC KD-D50 cassette deck. I found another one on eBay for 99 cents! (Okay, shipping was $20, but still....). So now I own 2, and one of them is to be sacrificed for a Frankenstein DIY project I have been thinking up in my head.

I want to cool LCD display--which I love so much and spent HOURS looking at during my teenage years--to be mounted in a stand-alone project box. It should be easy to accomplish. Check out the video below (made with my little Sony digital camera... not bad).





Ideally, this thing would just have stereo RCA inputs (and maybe outputs) with a volume pot on the side or back to adjust the levels. That's how it works in the deck, so it should be no problem. There are only 7 wires going into the board that is connected to the display. My current theories:

• RED/WHITE (pair): power
• BLACK/YELLOW (pair): R/L in or out
• PINK/PURPLE (pair): R/L in or out
• LIGHT BLUE (single): Who knows?

The stereo slider volume pot along the bottom must control the levels in; it can't be the LIGHT BLUE because the slider controls L/R separately. So I am nearly positive that I am correct about the functions above; problem is, I have no idea which is which.

I am guessing RED/WHITE is power because it goes to a separate board than the other two; it would make sense that the in and out R/L would go to the same board. I can test this easily by loosening one of the RED/WHITE to see if the display powers up. If the others were easily removed and reattached to the board, I could do the same checking the levels.

The trick will be (once I find out what is what) getting the fewest number of parts out of the deck for it to work. It would be great if the thing could be powered by an external wall wort. I might need some help on this one. Gonna send the video to my buddy Dave in the Electronics Dept. Or, hey! Our new hire Matthew in Electronics faculty is a fellow musician! I think I have this solved!

More On This Topic

I managed to purchase a PDF of the service manual for this puppy online. $22. Since the actual unit cost under a buck, this seems to make sense (the fact that I now own 2 of them is another reason). It will be cool to try to do this myself.

A Note About the KD-D50

I have never pretended that this box was a high end piece of gear. As a teenager, I lusted after the just-out-of-reach Nakamichi decks, and the way-way-out-of-reach Revox decks that I demoed at The Gramaphone and Almas Hi-Fi. I purchased this one with lawn mowing money in 1983 or 1984; I think I tried to buy it at a place on Woodward because they had the best price. I remember getting kicked out of the store because I was too young, and that pissed me off (my mother had dropped me off). So I ended up getting the thing at Almas, which was my favorite place. I got my Polks there before. I bought my cheap-ass receiver at Fretter Appliance, but that's another story.

So, the KD-D50 wasn't top of the line by any stretch of the imagination. But it was designed for making mix tapes (or at least it had that in mind). There was a tiny computer--more of a calculator really--that helped you guage with some precision how much time was left on a cassette. Tell the deck what length of tape you were using (e.g. C-60, C-90, C-120) and it would keep track of your remaining time. I spent MANY, MANY hours making tapes using this feature. I would have a legal pad with track titles and times, and this would allow me to fit the songs in without having a tape stop in the middle of a song.

A mixtape (or compilation tape) that went "ker-chlunk" and ended in the middle of the song was no good to anybody. Never, ever, ever, ever would I stand for that. Conversely, a tape that ended with only seconds of blank tape at the end was a thing of beauty. No need to fast forward or rewind before switching sides (this was before auto reverse decks were widely available--in fact, Nak made a great deck that actually physically flipped the tape, as opposed to moving the heads).