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6J1 Preamplifier

6J1 Preamplifier

I purchased this 6J1 amplifier from eBay. The seller was located in China. Below is a my experinces building the preamp. I have not had a chance to give it a full test. I will update this post once I have had that chance. 

It took a little over an hour and a half to finish building the kit. The board seemed a little tight for installing everything. The board itself runs on 12AC and from what I can gather it takes the 12AC and runs it through a voltage doubler which then gives the "B+" voltage.The tubes are 6J1's and obviously have 6volt filaments that run in series. I can not find a lot of info on the 6J1. Link to Data Sheet .

There is not a lot of instructions. Most everything is in chines and so I cannot read it. I was able to follow down the parts list and figure out what everything was and where everything went. I used a multimeter to check the resistors before installing them because the colors were not easy to interrupt. Overall this is a neat little preamp and an easy build.  

The box with a flash light for scale. 
The box.
These are the instruction. 


Here is the initial unpopulated board and the bag of parts.


Below is the finished kit.



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Comments

  1. UnknownJanuary 12, 2018 at 2:00 PM

    I just finished the same project. I ran into the same issues that you did.

    ReplyDelete
    Replies
    1. UnknownMay 2, 2018 at 5:00 PM

      Just bought the same kit through Wish. Is there anyway one of you could throw together some instructions on how to build this thing? Or maybe provide more detailed pictures so we can see where everything goes? You can email me directly at blumenthala@gmail.com.

      Thank you in advance if you can!

      Delete

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