Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: giampi97 on June 02, 2018, 12:32:38 PM

Title: doubt on resistance check
Post by: giampi97 on June 02, 2018, 12:32:38 PM
I' am writing this post because i was doing the final resistance check e it says that terminal 10 should have a 0 resistance with the ground, but how can it be 0 and not 2,49k, since it is connected with the white cable to the upper lug of the headphone jack that is connected to the ground through a 2.49K resistance?
Thanks, Giampietro
Title: Re: doubt on resistance check
Post by: Paul Birkeland on June 02, 2018, 12:44:35 PM
The headphone jacks shorts the 2.49K resistors to ground when no headphones are plugged in.
Title: Re: doubt on resistance check
Post by: giampi97 on June 03, 2018, 06:19:05 AM
Ok, then i don't know what is the problem. I have a full built crack (it's the first time i build an amp) and all the resistance and voltage checks are ok. Unfortunately I hear a loud disturbing noise (i tried it in different places, so it is not an external disturb). The strange thing is that if a give a little bump to the amp, the noise disappears for few minutes and then comes again.
Could it be a problem of cold joints?
Title: Re: doubt on resistance check
Post by: Paul Birkeland on June 03, 2018, 07:20:43 AM
Yes, that sounds like a cold joint or a joint that hasn't been soldered at all.  The most common joint that's problematic in the Crack is where the black wires meet at the headphone jack.