Re: YMI5150? 12003 build
Posted: Mon Aug 06, 2012 10:36 am
I don't think the attenuator would do it. What was your B voltage?
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YMI5150? 12003 build
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Re: YMI5150? 12003 build
Posted: Mon Aug 06, 2012 10:46 am
Looked back at page one of this thread it was 483 with wall voltage and down around 355 with the variac.
Re: YMI5150? 12003 build
Posted: Mon Aug 06, 2012 12:30 pm
Thats a ****** PT correct?
Re: YMI5150? 12003 build
Posted: Mon Aug 06, 2012 2:13 pm
Running on a variac should, in theory, be helpful for the trannies. I have had mine at 90 v and 350 something at the plates for several years.
No pop, nothing? When I blew the fuse, I got a good pop.
You may give Chris a call and see what he thinks, it is is tranny, right?
No pop, nothing? When I blew the fuse, I got a good pop.
You may give Chris a call and see what he thinks, it is is tranny, right?
Re: YMI5150? 12003 build
Posted: Mon Aug 06, 2012 2:16 pm
What does "mic'd" mean? Was the cab in a different room? What exactly was the set up?YMI5150? wrote:I was wearing my headphones listening to my rig mic'd and all the sudden i lost sound.
Re: YMI5150? 12003 build
Posted: Tue Oct 09, 2012 10:17 am
just to complete this thread, the PT has been replaced and is smokin! CM did a bit of investigating and determined that there was leakage current going back to the tranny, caused by either a bad rectifier diode or a main filter cap. i replaced everything. went away from NOS mains to newer parts. not worth the risk.
Re: YMI5150? 12003 build
Posted: Tue Oct 09, 2012 9:52 pm
I was planning on using some Erie 100ufs for the mains, is that what you were using? What did you replace them with, F&T?
Re: YMI5150? 12003 build
Posted: Thu Dec 27, 2012 3:03 pm
thought I'd document some changes I've made to the build.
added a NFB pot (white knob and all). wish I put it down past V1. excellent addition.
reduced one of the bright channel input resistors to 20k. makes upper bright input jack very hot and lower hole a great crunch channel. unfortuately you can't put a plug in both at the same time without affecting the results.
V1 for both normal and bright channels have the same values. normal is an awesome crunch channel. I made a foot switch that jumps to either. really nice rig. time to button it up. clips shortly.
added a NFB pot (white knob and all). wish I put it down past V1. excellent addition.
reduced one of the bright channel input resistors to 20k. makes upper bright input jack very hot and lower hole a great crunch channel. unfortuately you can't put a plug in both at the same time without affecting the results.
V1 for both normal and bright channels have the same values. normal is an awesome crunch channel. I made a foot switch that jumps to either. really nice rig. time to button it up. clips shortly.
Re: YMI5150? 12003 build
Posted: Thu Dec 27, 2012 3:12 pm
Did you notice any noise reduction with the 20k input resistor?
Re: YMI5150? 12003 build
Posted: Thu Jan 03, 2013 12:36 pm
For some reason, when I made my normal channel and bright channel the same spec, the bright channel sounded like poop. When I changed it back, all is well. Weird. I probably did something else wrong but who knows.YMI5150? wrote:thought I'd document some changes I've made to the build.
added a NFB pot (white knob and all). wish I put it down past V1. excellent addition.
reduced one of the bright channel input resistors to 20k. makes upper bright input jack very hot and lower hole a great crunch channel. unfortuately you can't put a plug in both at the same time without affecting the results.
added 33k fat cap.
changed mixer to 1000 pF. subtle but nice warmth. high end is smoother. worthy change with a strat.
V1 for both normal and bright channels have the same values. normal is an awesome crunch channel. I made a foot switch that jumps to either. really nice rig. time to button it up. clips shortly.
Why would you shut that amp up? It is so purdy inside.
Re: YMI5150? 12003 build
Posted: Sat Oct 25, 2014 10:30 pm
YMI5150? wrote:just to complete this thread, the PT has been replaced and is smokin! CM did a bit of investigating and determined that there was leakage current going back to the tranny, caused by either a bad rectifier diode or a main filter cap. i replaced everything. went away from NOS mains to newer parts. not worth the risk.
This ia crazy. I guess i have much to learn. So shitty main filters can take out a pt. hmm