5F1 Do I need to ground this output jack?

[cat]

Hi guys,

I am using the following modified 5F1 Layout.

I wanted to know if I need to run a wire from the speaker jack to ground where the OT ground attatches?



Thanks guys,

Cat

[tubeswell]

FWIW I always attach the OT secondary ground side to the output/speaker socket sleeve side (which I ground to the chassis) and my amps are pretty quiet.

[cat]

FWIW I always attach the OT secondary ground side to the output/speaker socket sleeve side (which I ground to the chassis) and my amps are pretty quiet.

Thanks for your reply tubeswell,

I got confused here because the layout doesnt show it but all the 5F1's Ive seen have the jacks star grounded.

Ill try it out, hopefully it will reduce some hum

Cat

[MWJB]

Use metal jack sockets that ground to the chassis (scrape away an paint/plating that might interfere with a good connection). ground your volume pot to #1 input jack ground, I'd also run the preamp filter cap to here. Should be ok with 6V6 cathode resistor, 220K grid load etc going to PT bolt star.

Where is your 25uf cap that bypasses the cathode resistor at V1, pin 3?

Run the grid wire from vol pot middle tap straight to V1, pin 7, not thru the board, use shielded wire ground the shield at one end only. Depending on how deep your chassis is, I'd do this with the wire to pin 2 from the jacks too, mount the 68Ks on the low gain jack socket, BF style (especially if a deeper, slide in/slide out style).

5W would be a better rating for the 6V6 cathode resistor.

I usually run the AC cord ground to it's own PT bolt, just because it's more convenient, no problems with doing this.