

only tranformer Fine met are $ 650 USD + amplifier cost
Get a Mazda octal socket such as PEN 25 PEN 45 or modify a US socket
The official product is not new, but I think it is a good idea to specify the socket and purchase it by mail order from Mella, a vacuum tube seller in Chile, South America.
When I lived in Chile 20 years ago, I bought some and brought them back to Japan.
I had a lot of trouble after that. I could get the vacuum tubes, but I didn't have the sockets. They may be available at ANDIX. I think it's best to make it yourself. I use a Teflon US octal socket made in China that is sold normally.
Remove the 8th pin and move it back about 1mm. I think you can do it with other sockets, but I think the Teflon socket is the easiest to modify. Please devise your own method of fixing.
The pins of this Mazda octal socket are the same size as normal US ones, but there are subtle differences. The vacuum tube seems to be inserted, but I can't insert it. The problem is the position of the 8th pin.
I don't know if it's off by a few millimeters overall, but if you move this 8th pin about 1 mm toward the 7th pin, it will insert perfectly. See the images below for reference.
Mr. Kakinuma's father at Sanei Electric used to say that if you widen the hole for the center pin with a file, it will fit, but I was unable to insert the PEN45.
All you need to do is order a Teflon socket from China. All you need to do is move pin 8 about 1mm closer to pin 7 and have them drill a hole for you.
It should be simple, but they can't do it. I think they will have to manufacture at least 10,000 units. It's a dream that an individual cannot achieve.
Then the mazda octal
The origin of Mazda is said to be something like the name that was taken from the bamboo that was used for fans from Kyoto when Edison invented the light bulb.
That is what they say Mazda is. It has nothing to do with Matsuda. I think it is the name of a light bulb manufacturer that emerged from that. For more information
Search on Google. In other words, light bulbs were made from the bamboo of a fan. It is a carbon light bulb.
The socket of the PEN 45 ended up with a larger hole. It is made larger than 7 pins and the pin is inserted. A stopper is attached with plated wire to prevent it from falling out.
This socket is a small hole, not a 32mm hole.
The hole is too large for a Japanese chassis punch and it falls out, so an auxiliary bracket is made from aluminum plate and attached, but if the hole saw hole matches, it will fit as it is.
If the chassis punch fits, no adapter is needed, and if you use the genuine 32mm product, it can be easily installed.
Before that, you need to make the hole larger with a file so that the guide fits perfectly.
According to the circuit diagram, it seems that the sound is best when used in the same way as the EL3N.
UL produces the best sound. The impedance of the output transformer is 7KΩ. I made several PEN45 single amplifiers without knowing the specifications,
It seems that the vacuum tubes of this era work best with a simple circuit like the circuit diagram I introduced.
There are almost countless vacuum tubes of this type with different vacuum tube sockets, but most are European vacuum tubes.
The pentode part of the PCL86 has very similar characteristics to recent vacuum tubes. It is no exaggeration to say that it is a small EL 156.
By the way, make the hole a little larger. It will give better results if it is a little wobbly.
However, if you can get the hole position exactly right, it's best, and you can just move the position of pin 8 nicely.

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