LL7903 PCB

High Level Mic Transformer PCB

I’ve used the LL7903 transformer for many years. It’s a fantastic transformer, very flexible and useful in valve amplifiers. I use them from SUT to phase splitting regardless. The performance and sound is sterling, as you can expect from Lundahl.

I always struggled with the lack of PCBs available to mount them so I ended up designing and fabricating my own ones. I added a set of jumpers to allow for all combinations to be available and configured as needed. No need to re-solder

Overview

  1. Step up transformer: 1+1+1+1 : 2+2+2+2
  2. Set up configuration options (selectable via jumpers)
    1. 1:2
    2. 1:4
    3. 1:8
  3. Centre tap available for phase splitting at the output
  4. PCB surface finish: ENIG Gold
  5. Connectors:
    1. Standard turrets / 2mm plugs

Price

I made a small batch so I’m selling them until they run out at £15 each plus Paypal taxes and shipping fees (see below)

Ordering PCB

If you want these PCBs, please fill out the form below. Thank you