Does anyone know where I might find the above parts? The transistors in this keyboard, DTC114ESATP and RN2227 are listed as obsolete. I found a substitution for the RN227 (KRA226M) but I can’t find it at any of the online sources I’ve tried (Jameco, Allied, Digikey, Mouser, Newark). I found a supplier for the IC’s, HD74HC245P and HD74HC138P but wonder if they are indeed legitimate as I’ve read lots of posts about counterfeit semiconductors. I’m not trained in electronics so I am not familiar with substituting obsolete parts with newer equivalents which are readily available. Thanks!
We have had luck finding obsolete transistors on eBay. The HD74HC… chips are pretty common and inexpensive, and I you don’t need to worry about counterfeits. That only applies to rare obsolete chips that sell for lots of money (like $60 per chip or so).
Thanks! I found most of the parts on Mouser. There are new chips from Texas Instruments that come up when looking for the original chip numbers. They seem to do what the original ones do. I did also see some of the transistors on eBay. Good info about the counterfeit transistors. I’m planning on removing the two chips on the Panel R board and installing sockets, then try it out. I may replace the transistors or not depending on what happens. I did manage to find a replacement Panel R board and main board so if my attempts fail, I believe I’ll be able to restore this board to playing condition.
In case anyone is interested. I finally got this piano to work. I ordered a main board and a panel R board from Ebay. Put them in and…nothing. The same as before, piano and all tones but only the first tier. Nothing below. None of the switches under the LCD functioned. Found a Panel L board and Jack Board and bought them. Installed them and now everything works as it should! At this point, I don’t know which of the 2 latest purchased boards did the job. My guess is the Jack Board because it supplies power but I have no way of knowing, short of taking everything apart and swapping boards. I now have spares but my guess is that the Main Board and the Panel R board are ok since the new ones made no difference. Anyway, it’s working and I’m done. Thanks to Sam for all his efforts to assist!!
Well, this is somewhat embarrassing. I was examining the original boards from the 330GX and lo and behold I discovered a crack in the Left Panel Board! I only saw it because I was looking at it under a different light than the one over the open piano. I saw the crack on the component side and turned it over and found several broken traces! I now believe this was why the piano wasn’t fully functional. Unfortunately, it cost me more money than I wanted to part with to fix this thing. The lesson is to better examine all pcbs when trying to troubleshoot a problem. Now it appears that I have a number of backup pcbs for this keyboard!
That’s a good reminder that a close inspection with a magnifying glass can be very revealing. Of course, when you started down this road, you didn’t know which board to even look at. It’s great news that you got it singing again!