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Yes, I will try to post a picture. TP8, TP9 and TP10 (ground) will be convenient to provide power to the fans. It will not be hard to mount the fans. Will try to accomplish it in a month.

I just did an experiment. I put a cooling pad for laptop computers over the hottest 4 transistors with one of the 2 fans directly over those transistors. I turned on the fans after 20 minutes of listening to the C-2A. I wait for about 2 minutes then check the temperature of those transistors by...

Actually I have not used it for 30 years. My buddy bought it (5 years used) about 20 years ago from a private owner. I went with my friend to the previous owner's place and bought it there. My friend had problems with it from time to time and eventually lost his confidence with this C-2A. He...

Yamaha C-2A looks like 4 little power amp inside. Two of them with feedback loop to make them RIAA equalizer. The other two with bass and treble control to make them do tone control. Some how the output transistors for the RIAA equalizer are mounted on the chassis for cooling. But the output...

C-2A's equalizer has 4 such output transistors. But they are mounted on the chassis for cooling. They don't get hot at all. The tone control amp also has these 4 transistors at the output stage. But they are not mounted on the chassis. They are standing right on the PCB without cooling. This...

I know those transistor's Tj is 150°C. But I am talking about the ones not fastened to the chassis. I am talking about the ones that have no heat sinks on them whatsoever. They are visible from the component side. They are much hotter than the TO-3 power transistors on my power amp. That doesn't...

I need to have 2 fans to cool the equalizer and the tone control amp. I think this will make a big difference if I want my C-2a to live longer. I have got some idea how to mount then and power them. I will need to find appropriate DC fans. It will take some time. But I would like to stop the...

The electrolytic caps inside the preamp all look like new. There is really no way to tell if any of them have aged to a point needs to be replaced. I checked TP8 and TP9 with a scope and there is no AC ripples. So I can assume that the power supply regulator is working just fine.

The Japanese site shows some replaced transistors (2SC1913 and 2SA913). Based on the pictures the 4 hot transistors on the tone control amp are replaced. This confirms that these transistors are way too hot. They are likely to die and need to be replaced. I am considering to install a very small...

There are 4 TO-5 transistors that run really hot. After 10 minutes of playing they are so hot that it will burn your skin if you dare to touch them. A few resistors nearby those hot transistors are apparently protected by teflon tubes. The amp modules (equalizer and tone control) are capacitor...

I don't know about the condition of the two big supply capacitors. But I hooked up a oscilloscope to check the DC voltages there isn't any AC ripples. The DC supply is heavily regulated out of unregulated +/- 60V. The regulator transistors have heat sink (bottom chassis) on them. I did...

Recently my almost 30 year old Yamaha C-2A preamp started giving sharp punchy pops. When it does that it gives consecutive 3 - 5 pops then stops. It may do it again a few minutes later or it may not do it at all in a week. But it always comes to annoy everyone in the middle of a piece of...