Well I built a Broadcast without the transformer

HamishR

Well-known member
Broadcast mod.JPG

Although it times it felt like I had just opened a box and tipped a bunch of electrolytic caps into it. 🤪

The pedal isn't finished yet as I will be putting a 4-knob OD into it as well, the Broadcast being used as a boost for the OD. But the Broadcast is working. And it sounds great - much like a regular Broadcast but maybe a tad louder? Hard to say. Leaving out the transformer doesn't seem to have hurt it at all - it sounds much the same as my other two which were built stock on Pedal PCB boards. One was a Duocast, the other a Broadcast. In all of them I have used a Russian MP20 PNP Ge transistor which works very well.

I guess that if the transformer was a 1:1 maybe they used it to avoid interference with other effects? I don't know, but I do know it sounds bloody great without the transformer too. The Vero board is larger than I like - it will fit into a 125 but not a 1590B. Some of those caps are huge.
 
Hudson Broadcast Mod.png

And I know it works! If you like you can add a single row at the top to get the resistors properly vertical but I was battling for space for a dual pedal. You can see how close the board gets to the input socket - It's actually not as close as it looks and putting the lid on the box pushes the board down a bit further anyway. This layout allows you to fit a transistor socket for the Ge transistor and also has room for the ridiculously large capacitors - in the case of the 330µF only just. Also note that pins 1, 5, 6 & 7 of the LT1054 are not connected. I did this as shown in the drawing by drilling off the copper under those pins of the socket and it worked great. It also saved some space because you'll want to make cuts for those anyway.
 
And I know it works! If you like you can add a single row at the top to get the resistors properly vertical but I was battling for space for a dual pedal. You can see how close the board gets to the input socket - It's actually not as close as it looks and putting the lid on the box pushes the board down a bit further anyway. This layout allows you to fit a transistor socket for the Ge transistor and also has room for the ridiculously large capacitors - in the case of the 330µF only just. Also note that pins 1, 5, 6 & 7 of the LT1054 are not connected. I did this as shown in the drawing by drilling off the copper under those pins of the socket and it worked great. It also saved some space because you'll want to make cuts for those anyway.
A 1590Q is a Great alternative:

Broadcast1590Q mod.jpg
 
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