coax confused?

[echo44]

Ok so I am building a #124 took the advice and bought some teflon coax
from apex jr, bought the thin stuff and the thick stuff not sure which is better?

So my first run is from V1 to the input jack. Do you use the braiding for the conduct or the center wire or both? I notice on some pictures some portions of the amp use the braiding to ground
help
sincelrly,
mega confused rookie

[ToneMerc]

Concerning the input jack to V1, I ground the braid only at the socket terminal.

TM

[echo44]

any pictures?

[LeftyStrat]

The braid connects to ground at one end, typically at the jack. This is to shield the signal that runs on the inner connector from noise. If your input jack is isolated, ie. plastic, you'll need to run a connection from the ground lug of the jack to the preamp ground point.

[ToneMerc]

any pictures?

[echo44]

Thanks! so the braid only needs to connect to ground on one side
usually at the jack?

[ToneMerc]

Thanks! so the braid only needs to connect to ground on one side
usually at the jack?

Personally do it as I've seen in more than one actual HAD build, at the V1 terminal. See the input jack drawing above and the #177 pic.

TM

[echo44]

I see thanks, so you twist the braid into a wire that comes off the back side of the heat shrink and connect to center post to ground.
what are you using for goop, I also notice on the actual Dumble #!24
pictures in addition to the blue goop he uses some black stuff?
do you know why that is? Thanks again sooo much only another couple years and ill have this thing finished

[boldaslove6789]

In #177 the goop is obviously used to protect the amp from "Bootleggers" (LOL, as HAD says) but also doubles as support for the HRM board.

If you want to be authentic you can goop the preamp but it's not necessary, you can just use stand off's instead.

Yes #177 has the input coax grounded to the center ground lug of the terminal strip on V1.

[ToneMerc]

I see thanks, so you twist the braid into a wire that comes off the back side of the heat shrink and connect to center post to ground.
what are you using for goop, I also notice on the actual Dumble #!24
pictures in addition to the blue goop he uses some black stuff?
do you know why that is? Thanks again sooo much only another couple years and ill have this thing finished

I don't disturb the braid at all. I expose the braid and carefully solder a 20 or 22awg drain wire to the braid. The blue and or black "bootleggers" goop that HAD used is Permatex gasket sealant.

TM