Up for sale here is this P700 amplifier board rebuild & repair kit for a Marantz 4230. This is all the parts you need to rebuild ONE Marantz 4230 amplifier board. There are TWO amplifier boards in a 4230, so if you need to rebuild both amp boards, set the quantity to 2 when you buy. Over time the amp boards start developing issues with diodes, transistors, and capacitors, and sometimes completely blow up. The old parts are weak and failing. We will make them new again!

This is a complete kit--it includes all 17 capacitors (replacements for all the electrolytic capacitors, including the two 3300 uf 35v caps), 2 diodes (replacements for the M8513 A-O diodes), and 17 transistors (replacements for all the transistors on the board, plus 4 new output transistors). It also includes 4 new mica insulators for the new output transistors. It does NOT include any resistors, so if you have burnt resistors you'll need to replace those.

This kit will completely rebuild one P700 board, so it's intended to repair boards that have been blown up or are otherwise non-working.

These are all high-quality brand new genuine parts. The capacitors are Nichicon PW and FW and Wima film caps at the correct uf and the same or higher voltage ratings, and the transistors and diodes are Fairchild/Onsemi and are the correct subs for the original transistors/diodes. These are extremely high-quality parts, and they are what I use when I rebuild Marantz gear. Frankly, "recapping" is a waste of time if you're not going to replace the transistors as well. A lot of times the transistors age worse than the caps, so you should definitely change out the transistors while you're in there. If you're having amp board issues, it's very likely to be a transistor issue.

Please note that the new TIP41C output transistors have a different package design (TO-220) than the original output transistors (TO-66). These are the best replacements for the originals, and it's worth updating them to prevent future issues.

I will include an extremely specific instruction sheet designed to walk you through this, but this is a pretty complicated repair, so if you don't have much experience with this, buy the kit and take it to a professional. You should definitely have a fair amount of soldering experience and have a decent soldering iron, a dim-bulb tester, and heat-sink compound, as well as the usual tools. This kit may not fix your Marantz if it has other issues, but it will definitely help it run better, and should fix most amp board problems. Please see my pictures for details.

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.