First Time Crack Builder Need Assistance [solved]

[prtuc2]

The amplifier doesn't start up at all and now I am puzzle.  All the resistance values are within 10-15% and I follow all the steps on the voltage check before plugging into anything.  No smoke or it seems no current is running through the amp, tubes and any parts of the amp does not get warm at all.

[fullheadofnothing]

The fuse needs to be in the lower section of the fuse holder. Is that where you installed it?

[Chris65]

As shown here:

[prtuc2]

Thanks, that was the problem I install the fuse in the upper compartment.  Now everything powers on, but my voltage reading left me worry.

Most of the 90V reading I got somewhere between 70-72.5V that is outside of the 15% range, but my B1 reading start off at 1.8V now slowly climbing to 6V as I type is that sign of bad soldering? The reading move very slow.

[Paul Birkeland]

T1/T5 being in the 70's is just a sign of a very strong 12AU7, and is not a problem.

B1 connects to T1, you won't get 70V on T1 without 70V on B1 unless there is a miswire, or potentially if you have mounted the 8 pin socket with the keyway facing an improper direction.

-PB

[prtuc2]

On the second time power up I was able get B1 to hit the low 70s voltage.  I noticed I was having a little hard time inserting the RCA cable into the white RCA jack, then as I use my headphone to test out the amplifier something new happen.  At the first 2 minutes of the song everything seems fine, then I start hearing crackling sound then eventually shortly after the right channel of my headphone completely gone.  I re-test the headphone on my other amplifier it is still functional, but now I have a new problem to solve. 

Thanks for any input.

[prtuc2]

I check over the resistance values and the voltage values after the crackling sound heard, voltages are closer to the actual values now.  Could it be a bad tube? If the problem is the tube do I need an adapter to use 5998 or other tube like 6SN7 type of tube?

[Paul Birkeland]

This is usually a flaky solder joint.

-PB

[prtuc2]

It seems the more I do the more problems I am running into. 

The first thing I did was to resolder all the terminals that doesn't have a shiny finish and I redo the RCA center pins area but I might have mess it up.  Inside the center pins there is some solder left over that I can't remove so I just place the white cable into that RCA jack. 

Then I recheck the resistance and voltage values all within range.  Right before I try to turn off the amp and in the process I noticed the led on A3 and A8 both went out.  I proceed connecting to the DAC and headphone in place to check for sound.  No sound at all.

I power down the amp and unplug the power cord, checking the resistance values now show OL in most of the terminals.  So, lost in what is going on.  Not sure if the multimeter playing trick or I am doing something terribly wrong.

Thanks for any input.

[Paul Birkeland]

Do the tubes still glow?

[prtuc2]

Yes, the tubes seems fine.  The voltage and resistance reading is hit or miss sometimes I got the values all within range, next time I measure it will be different.

[Paul Birkeland]

I would recommend reporting any resistance readings that are not correct.

-PB

[prtuc2]

This measurement is taken more than 8 hours after I power down my amp and with the tubes inserted.

Resistance
1               >1000K ohms
2               >1000K ohms
3               OL
4               >1000k ohms
5               >1000k ohms
6-10          OL
12             0.2 ohms
13             >800k ohms, but slowly dropping my meter can't get the actual value on this terminal less than 10mins
14             0.5 ohms
20             0.2 ohms
22             OL <---? I didn't solder this on page 19 under revision I connected to 14U instead
B3             OL
B6             OL
RCA ground    OL
Center      OL

[Paul Birkeland]

Terminal 3 is connected to the chassis plate.

A wire goes from 12 to the lower set of lugs on the headphone jack, then from there to terminal 3.

Getting OL between 12 and 3 means that this wire is not connected.

[prtuc2]

Thanks for the all the help so far, now everything is up and running.  But, on the right channel of my headphone there is a pop sound like every 30 seconds, what could be the problem?