Harbinger One with 9v Question (again)

[pryde]

I am populating the harbinger and am going to run in at 9v AND use the filter pcb. My question is do I need to include or omit C32.

I know it says for 18v only but not sure if it needs included, omited, or jumped when using the filter pcb with 9v?

Thanks for the help.

[midwayfair]

I know it says for 18v only but not sure if it needs included, omited, or jumped when using the filter pcb with 9v?

Let's look at the schematic. What's that little guy doing?

Well, it's between +XV (DC) and ground. That should eliminate the jumper possibility, right?

We usually have a 100nF cap from power to ground to compensate for electrolytic caps not filtering high frequencies well (I think it's partly due to their internal resistance). Is such a cap on your filtering PCB? If not, then you probably want it. If it is, there's no hard in including it and probably no benefit.

[pryde]

Thanks Jon,

This one is a bit confusing as there is onboard filtering and separate filtering as well on the breakout pcb. Not sure if we need one or both systems and if using both would cause problems, etc.

I will go ahead and use C32 it as the filter pcb only has 2 large electro filter caps

[madbean]

This one is a bit confusing as there is onboard filtering and separate filtering as well on the breakout pcb. Not sure if we need one or both systems and if using both would cause problems, etc.

This is explained on page 6 of the doc with the Power Options chart.

9v DC Wall Wart (One Spot, etc.)   Populate the filter PCB and connect it to the 9v/G pads on the main PCB. Omit C22, D1.
9v DC Regulated (VoodooLabs, etc.)   Do not populate the filter board. Connect DC jack to the 9v/G pads on the main PCB. Use IC1, C22, D1, D2, D3, C19 and C20.
18v DC Wall Wart (Dunlop, etc)   Populate the filter PCB and connect it to the 18v/G pads on the main PCB. Omit IC1, C22, D1, D2, D3, C19 and C20.
18v DC Regulated (Voodoolabs, etc).   Do not populate the filter PCB. Connect the DC jack to the 18v/G pads on the main PCB. Omit IC1, C22, D1, D2, D3 and C19, but use C20.


I probably should have mentioned the 100n cap, but as Jon said: there's no harm in using it in all cases. It's probably most beneficial with wallwarts, but it doesn't hurt, either.