Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: davidwpack on July 21, 2017, 10:50:22 am

Title: Shielded?
Post by: davidwpack on July 21, 2017, 10:50:22 am
Hey there again. Just gotta quick question. Going from the middle lug of the volume pot to V1-7; should this be shielded cable? I used it from input to V1-2 but wasn't sure if it was necessary for V1-7. Thanks again!...Dave
Title: Re: Shielded?
Post by: kagliostro on July 21, 2017, 11:22:15 am
Not strictly necessary

give a try without

(It depends from many factors)

Franco
Title: Re: Shielded?
Post by: shooter on July 21, 2017, 11:27:39 am
Quote
give a try without
+1

If you do use shielded, use the same "rules" and only ground 1 side, typically closest to the incoming signal
Title: Re: Shielded?
Post by: davidwpack on July 21, 2017, 11:43:45 am
OK. I appreciate the quick responses!...Dave
Title: Re: Shielded?
Post by: sluckey on July 21, 2017, 12:52:09 pm
Quote
should this be shielded cable?
Depends on the layout. I would not bother if the run is only 2-3 inches or less. But if the pot is on the front of the chassis and the tube is on the back side, I would use shielded cable. Ground one end ONLY at the pot.
Title: Re: Shielded?
Post by: davidwpack on July 21, 2017, 01:05:37 pm
Yeah, they're on opposite sides. Around 5 1/2 inches probly. Thanks. Sluckey, I was looking at your project. I thought my heater wires looked pretty good till I saw yours. Comparatively mine are awful. Do you use stranded wire for your heaters? Anyways very nice looking work.
Title: Re: Shielded?
Post by: sluckey on July 21, 2017, 01:10:38 pm
I use 20AWG stranded Teflon insulated wires for all filaments. I like the 19 strands rather than 7 strands.
Title: Re: Shielded?
Post by: davidwpack on July 21, 2017, 01:13:31 pm
Ok. Thanks. More practice I guess, ey?
Title: Re: Shielded?
Post by: sluckey on July 21, 2017, 01:17:28 pm
Quote from: davidwpack on July 21, 2017, 01:13:31 pm
Ok. Thanks. More practice I guess, ey?
Maybe. It takes me a long time to run filaments like that. Filament strings is the least enjoyable part of the building process for me.
Title: Re: Shielded?
Post by: davidwpack on July 21, 2017, 01:25:48 pm
Yep, mine too. Especially when soldering to the preamp sockets.