SE ODS

[greekie]

Surfsup's got it right. Dad agrees as well.

[Colossal]

On most amps I build, I typically elevate the heaters to DC and usually to a purpose-made node on the B+. Cathode biased amps get the filament center tap connected to the output tube cathode bypass cap or p/p get their own 50-70VDC reference off the rail.

[martin manning]

You connect the cathode (minus pole) of the first filter cap to the cathode (pin 3) of the power tube. That way the power supply hum will be injected out of phase.

But be aware that injecting a hum cancellation signal at any cathode will be ineffective if the Rk is bypassed

[surfsup]

But be aware that injecting a hum cancellation signal at any cathode will be ineffective if the Rk is bypassed

Two caps in series make an AC voltage divider just like resistors. If the ratio of the capacitance values is the inverse of the value of the gain of the stage, why would this be ineffective?

[Colossal]

Q: In considering the layout, is it advisable to put the first treble peaker circuit (500pF/220k) mounted on terminal strips directly at the socket along with the LNFB circuit? Or is it reasonable to put the peaker components on the eyelet board, located pretty much in physical series with the Clean Volume pot's wiper, then following the wire...on to the board, through the peaker, then out to the socket.

Space will be a premium in the chassis so spatial constraints may end up dictating that I might the peaker on terminal strips, right at V1 socket along with the LNFB.

Just thought I'd ask to see if there were any ideas or suggestions on this.

EDIT: Corrected pF value.

[martin manning]

This is V2b (or Cl 2) right? I see 500p/220k. As for where to put it, ask yourself WWDD? Check the ODS layouts...

Cool project you've got here, BTW.

[Colossal]

This is V2b (or Cl 2) right? I see 500p/220k.

Whoops, you're right. Good catch; that should be 500pF, not 22nF. Corrected in post above.

As for where to put it, ask yourself WWDD? Check the ODS layouts...

D would mount it on a terminal strip. Makes it simple. Done and done.

Cool project you've got here, BTW.

Thanks! Should be a fun build.