F5 Turbo Builders Thread

Had a huge hum problem with 2 channels at the input. With only one nothing at all. Solution must be a little resistor in the gnd in?

Jims Pcb



Have you tried the PSU / grounding suggested by NP for the f5 turbo?

f5TV2_psu.png
 
Please note the different symbols used for the chassis ground/Safety Earth/PE and the PSU power ground/PSU zero volts.
This is important.

Note also that the secondary centre tap goes directly to the first capacitor pair.

having got those bits wired correctly it becomes important to minimise the loop areas of the charging circuits to minimise the EMI.
 
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Gnd enclosure

As my backplate is not metal I could have a problem with electrical connection of the enclosure parts. I'll connect the two heatsinks at the backplate with a copper 2 cm wide and ground my input to that trough 10 ohm and a capacitor. Do you think that's an idea? ? I can't post pictures even that I have paid Diyaudio 20 dollars for membership.
 

6L6

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By having an extremely low-impedance and low resistance ground. The easiest way to try it is attach ALL (including the signal input grounds) to one point on the PSU ground. Star-grounding is a common name for it.

An externally hosted image should be here but it was not working when we last tested it.


Do this. Attach the speaker negatives and the input signal negatives to it as well. (Yes, the input from the RCA to the PCB will only be the positive!) The only ground connection from the amplifier boards will be the one wire attaching V+/gnd/V- to the PSU.