10 New DIY Kits For BA312 IC Chip Replacements (Boards Transistors & Resistors)

Description: Up for sale here is this set of 10 (ten) brand new bare boards with all necessary parts to build 10 replacements for the BA312 IC chip. This chip frequently goes bad in vintage receivers such as the Sansui 9090DB, Sansui 881, and Marantz 2275, and can cause you to have weak or distorted sound. The chip has been discontinued for decades, and is difficult to find, but luckily some fine folks on Audiokarma designed a replacement for it. These boards will let you build that replacement! While some boards are built with tiny SMD parts that are extremely difficult to work with, these boards are designed to use through-hole parts that normal people can install. Each board measures 19.4mm x 15.3mm and is 1.57mm thick. With all parts installed, if you mount the transistor as low as I did, it will be about 10mm thick, which includes the solder joints. I have shown a picture of what this looks like once it's assembled, but this listing is just for the ten bare boards and the parts to build your own. Assembly and installation is fairly easy--you will need a soldering iron and solder. I would recommend a fairly fine-point soldering iron (and thin solder), as a wider "chisel tip" will make this difficult. I used a Hakko iron with a 1mm tip and it worked well. I strongly recommend you replace all the electrolytic and tantalum capacitors on the board that has the BA312, or at least replace the ones that are surrounding the BA312. These chips sometimes go bad due to shorted or leaky capacitors, so you need to replace the bad caps so the new replacement doesn't have issues. Assembly is simple. There are 40 new 1/4W resistors in the kit. You can use a multimeter to determine which are which. For each board, the 5.1k ohm resistor goes in R1, the 10k ohm resistor goes in R2, the 51-ohm resistor goes in R3, and the 180-ohm resistor goes in R4. There are 30 new Onsemi KSC1845FTA transistors in the kit. These are installed in the Q1, Q2, and Q3 slots. They all go in the same way, facing the upper right corner of the board. This listing has a picture of a completed board, so you can see exactly how they go in, or you can just use the board markings. All parts should be installed as low on the board as possible so this can be installed without issues. You will end up with 8 long wire bits from the resistors, which can be inserted in holes 1-7 so you can solder this to the receiver's circuit board. The board is marked for easy assembly. If you want to buy just the bare board itself, I have that here. If you want to buy a board that's already assembled, I have that available here. If you want to buy a genuine NOS unused BA312 chip, I have that available here. US shipping and handling is $5, and international is $18, no matter what quantity you buy. All my small parts are set up for combined shipping, so just use the "add to cart" feature and then check out all at once, and it will combine shipping. If you have any questions, please ask. Looking for more parts? I have power switches, feet, pushbuttons, top case screws, bottom screws, faceplate screws, white LED fuse lamps, blue LED fuse lamps, 6.3v bi-pin bulbs, 8v bi-pin bulbs, 12v bi-pin bulbs, wired 8v 60ma bulbs, new power cords, new main capacitors for the Marantz 1060/2230, wired Pioneer speaker plug replacements, new 630v yellow film capacitors at 38 different values, new 1200v yellow film capacitors at 15 values, a large variety of transistors for vintage stereo repair, new Wima film capacitors for stereo repair, new 250v yellow film crossover capacitors, and more. Just use "add to cart" on everything you want and then check out for combined shipping.

Price: 35 USD

Location: Milwaukee, Wisconsin

End Time: 2024-07-09T21:14:59.000Z

Shipping Cost: 5 USD