Well I guess regardless of which side of R13 you measured, 227V there indicated the tube is conducting. If you put the meter test leads across R23, then we'll know if the tube is getting the right amount of current. It probably is, but it doesn't hurt to check. Also measure across R17 and R27 to see if the output tubes are doing the same.
Just ordered the caps and resistors for mine 
And from what you guys are saying, I'd better get my textbooks out of storage too. NO, NO, don't say RLC circuits!! LOL. I had Prof. Jackson at URI for my analog circuits class and for linear systems a couple years ago as an older student. This is his book
http://www.amazon.com/Signals-Systems-Transforms-Leland-Jackson/dp/0201095890/ref=ntt_at_ep_dpt_1
Hardest class I've ever had by far. Wow. I'm still in pain
And now I have to relive some of that 
Well worth it, though, gotta love this stuff 
And from what you guys are saying, I'd better get my textbooks out of storage too. NO, NO, don't say RLC circuits!! LOL. I had Prof. Jackson at URI for my analog circuits class and for linear systems a couple years ago as an older student. This is his book http://www.amazon.com/Signals-Systems-Transforms-Leland-Jackson/dp/0201095890/ref=ntt_at_ep_dpt_1
Hardest class I've ever had by far. Wow. I'm still in pain
And now I have to relive some of that Well worth it, though, gotta love this stuff 
sailWickedFast said:
Hardest class I've ever had by far. Wow. I'm still in pain
just be thankful that you aren't dealing with field theory here... Thats the stuff that always messes with my brain.
So new thread when you start yours sail?
Hey Guys,
Made some progress. I measured the B+ voltages on T3-PRI 03 and on T2 PRI 03 and got 432V and 434V respectively.
I then changed out my speakers Sansui SP-2000 to some cheapie Kenwood suround-sound speakers with a small driver and bingo, I can hear some faint music. It is loud enought that I can hear them maybe 2 ft away from the speaker but its extremely low.
I do not have a volume control connected so is that my problem? R11 and R21 (220K) I believe control the volume if no volume pot is used correct? I do have a 50K volume pot that I purchased from I think Mouser. I did not add a volume pot because I plan on connecting a preamp at a later time (with a phono input). I thought my ipod would give me enought volume gain to not require a pot. Any thing else I should check or suggestions?
Thanks,
Skipper
Made some progress. I measured the B+ voltages on T3-PRI 03 and on T2 PRI 03 and got 432V and 434V respectively.
I then changed out my speakers Sansui SP-2000 to some cheapie Kenwood suround-sound speakers with a small driver and bingo, I can hear some faint music. It is loud enought that I can hear them maybe 2 ft away from the speaker but its extremely low.
I do not have a volume control connected so is that my problem? R11 and R21 (220K) I believe control the volume if no volume pot is used correct? I do have a 50K volume pot that I purchased from I think Mouser. I did not add a volume pot because I plan on connecting a preamp at a later time (with a phono input). I thought my ipod would give me enought volume gain to not require a pot. Any thing else I should check or suggestions?
Thanks,
Skipper
The Simple SE should have plenty of gain to drive any normal pair of speakers to clearly audible levels, even with an iPod as the source input. The absence of a volume pot is not the problem.
I'd go back with the ohmmeter and confirm the values of the resistors. Someone once got the wrong value at R15/R25 and that resulted in very low volume.
I would also visually examine the wiring at the output transformer. Make sure you didn't somehow get both speaker binding posts accidentally connected to ground. Did you use cathode feedback, or a switch for enabling cathode feedback?
I'd go back with the ohmmeter and confirm the values of the resistors. Someone once got the wrong value at R15/R25 and that resulted in very low volume.
I would also visually examine the wiring at the output transformer. Make sure you didn't somehow get both speaker binding posts accidentally connected to ground. Did you use cathode feedback, or a switch for enabling cathode feedback?
I will go back and check my resistor values again.
I did not add a cathode feedback or a switch because it was recommended to first get the amp up in running in the simplest triode form. I would like to add one late to hear what the difference sounds like.
The speaker binding post I not sure if they are correct. Since I have everything set up on a test bench, the binding post are not screwed into a metal chassis. Both negative binding post I have grounded the center wire connection to my ground and to the board as per the wire diagrams.
The postitive post, the center pin wire is going to by board but I am not sure if anything is suppose to be grounded. I figure that when it is attached to a metal chassis, the locking nut is grounded. Although my binding post don't seem to have an isolated gound from the input.
I did not add a cathode feedback or a switch because it was recommended to first get the amp up in running in the simplest triode form. I would like to add one late to hear what the difference sounds like.
The speaker binding post I not sure if they are correct. Since I have everything set up on a test bench, the binding post are not screwed into a metal chassis. Both negative binding post I have grounded the center wire connection to my ground and to the board as per the wire diagrams.
The postitive post, the center pin wire is going to by board but I am not sure if anything is suppose to be grounded. I figure that when it is attached to a metal chassis, the locking nut is grounded. Although my binding post don't seem to have an isolated gound from the input.
Skipper: As already mentioned, check for wiring problems. If the signal input side or the speaker binding posts are grounded, it will reduce the output to zero or next to nothing. If the input signal is tied to ground thru a relatively low value R, it will be significantly attenuated. Step back and check the obvious stuff before unsoldering R's, etc.
oldmanStrat said:
Yeah, those Laplace and Fourier transforms made me wanna cry at times to say the least lol.
Yup, just got my board from George at TubeLab today (thanks George!!) as well as the caps and resistors from Mouser, so I can get started this weekend at least, and also create a build thread of my own with progress updates, etc.
I just saw your email asking for a tracking number. For some reason your email went to my Bellsouth email address. I don't know how this happens (but it does occasionally). Did you reply to the Paypal confirmation? If so, it must be a Paypal screw up.
I don't use the USPS tracking numbers since they charge you extra for a tracking number, and it doesn't even register in their system until about 3 days after the board gets delivered.
Calculus, WHAZZAT! Useless stuff once you get out of school.
No, their only purpose is to provide a ground path for the grid of the tube. With no volume pot, there is no control. It is the same as having a volume pot that is turned up all the time.
It is difficult to troubleshoot your symptoms given the information present. The voltage readings that you have provided indicate that the board is likely OK. Measure the voltage at R17 and R27. Something in the 30 to 50 volt range indicates that the output tubes are conducting properly. The problem is likely in the input or speaker wiring.
For a quick sanity check, disconnect the secondary wires (blue and black) on your OPT's from the jacks and the board. Connect them directly to your speakers. Test again. Sound? If so something in your speaker jack wiring is messed up. No sound? Then the problem is likely in the input wiring. How do you have the iPod connected? Do you have a CD palyer that you can use for a test? If so connect it directly to the input jacks. It should be loud!
tubelab.com said:
Yup, I did get a confirmation of payment sent on PayPal. That email address is listed as contact info on your PayPal account.
Yeah, the USPS can be tedious to use at best
No big deal, though, I'm totally happy with my purchase Thanks again!Yes, doesn't make for very effective dinner conversation at all
OK, that explains why I occasionally get Tubelab related questions to that email address. I have both email addresses registered with Paypal. I use the Bellsouth address when bidding on Ebay stuff that's not Tubelab related. That email box gets blasted with tons of spam daily so it is possible that stuff gets missed. Fortunately I recognized your name.
Unfortunately they are the only choice for small items like PC boards, especially overseas. Their tracking is useless and not even available internationally. Fortunately lost boards are rare. UPS or Fedex wants $30 to deliver one PC board overseas.
I work in a building that used to house over 1000 engineers (before layoffs). It isn't effective conversation there either, but then neither is tubes!
Rknize,
according to the Edcor info that came with my PWRT, brown is for 5V and yellow is 6.3V. Is this what you recall for your XPWR059?
So here is what I have done. As suggested I connected the speaker cables directly to the OPT (no binding post) and still super low volume.
I've changed out the input RCA jacks with different ones and still no change.
I've measured R17 and R27 and got 36.6V and 35.5V respectively.
I started to ohm out the resistors on the board but it seems that most of them do not read correctly because they are tide into the board. So, maybe I will just try to read the bands on them. I should also not that both channels have the low volume. Do I maybe have a dry joint, can that cause this condition?
Anything else I should check? I am so close but this now has me puzzled
according to the Edcor info that came with my PWRT, brown is for 5V and yellow is 6.3V. Is this what you recall for your XPWR059?
So here is what I have done. As suggested I connected the speaker cables directly to the OPT (no binding post) and still super low volume.
I've changed out the input RCA jacks with different ones and still no change.
I've measured R17 and R27 and got 36.6V and 35.5V respectively.
I started to ohm out the resistors on the board but it seems that most of them do not read correctly because they are tide into the board. So, maybe I will just try to read the bands on them. I should also not that both channels have the low volume. Do I maybe have a dry joint, can that cause this condition?
Anything else I should check? I am so close but this now has me puzzled
Mine was intuitive: yellow is 5V and brown is the old skool 6.3 winding color. It could be that they swapped the wires by accident and updated the label accordingly or it could be a typo on the label. I don't think that running the tube heaters at 5V would make a huge difference, but its worth checking because the 5AR4 would not like 6.3V very much.
Yellow should be 5 volt. Green or brown should be 6.3 volt. I would not expect Edcor to arbitrarily swap color standards which have been in effect for over fifty years. I can't find the XPWR059 on Edcor's site, but they've got plenty of other power transformers with 5 volt and 6.3 volt windings. They use yellow for 5 volt and brown for 6.3 volt. See one example here: http://www.edcorusa.com/Products/ShowProduct.aspx?ID=623
Running the signal and output tubes on 5 volt heaters would definitely make a difference. They're just not going to emit as much as they should. That could easily explain the lack of volume.
Running the rectifier tube on 6.3 volt for extended periods of time will certainly damage it.
My power transformer is a Hammond, not an Edcor, but you can see where I put the yellow and green wires.
Running the signal and output tubes on 5 volt heaters would definitely make a difference. They're just not going to emit as much as they should. That could easily explain the lack of volume.
Running the rectifier tube on 6.3 volt for extended periods of time will certainly damage it.
My power transformer is a Hammond, not an Edcor, but you can see where I put the yellow and green wires.
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