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Hi there!
I have a LL1660/10mA that I'd like to use for a preamp output. I will be using a 12B4A, so I'd like to run at least 20mA or more if possible. In addition, I'd prefer a 1:1 or even a step-down to optimize output impedance.
So I'm guessing I can run the Alt T connection to double the current. Can I configure the secondaries in parallel (i.e. connect 13 to 21, 16 to 18) to get to a roughly 1:1?
Thanks in advance.
Robert
Robert
Follow Ups:
What you suggest will work fine, but you can get closer to your goal by using the Alt Q secondary or Alt T primary connections for the secondary with the primaries in parallel like Alt V. Yes, the table says the "magnetic midpoint" is reached at 18mA instead of 20mA and you want to use more current, but if you look at the bottom entry of the Alt V spec table, you see Max output at 230Vrms. It's unlikely that you are asking for anywhere near that output swing (;+)), so use 20mA or more, if it sounds better. At 36mA your core will be essentially saturated, so I would not raise the current above 30mA.
Kevin Carter
K&K Audio
www.kandkaudio.com
That's awesome, Kevin. Thank you very much. So it sounds like if I use the Alt V configuration is primary (connect 21 to 13, 16 to 18) and the Alt T primary connections as secondary, I should theoretically get 2.25:2 turns ratio which is perfect. I should be able to easily keep current down to 25 mA or less.
Robert
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