[adamus]

yes, that where it should be, and you said earlier og is 12v with respect to sg so the rail splitter is working too.

and if you remove the tube, the e12 still doesnt click?

 

[arteom]

Yeah, I get no click on the e12, the led doesn't go on at all.

 

[adamus]

what, its not red or green?

 

[arteom]

yeah, it doesn't turn on at all.

edit: to clarify I mean the bi-color LED.

 

[adamus]

can you carefully measure the pins on the e12 opamp (ICE), pin numbers are on the link in my previous posts.

be careful and done short anything.

I find a beer or three helps steady the hands

 

[arteom]

hahaha, yeah a beer wouldn't be too bad about now

here are the readings off the ICE opamp:

pin1 - .06v
pin2 - 12.6v
pin3 - 12v
pin4 - 0v
pin5 - .1v
pin6 - 2.6v
pin7 - 24.1v
pin8 - 0v

Thanks for the help!

 

[holland]

Quote:

Originally Posted by arteom /img/forum/go_quote.gif Oh, right . Well I have replaced the ICH, ICP and Q1P and Q2P. At this point I am not getting a green or red light but am getting a reading from SG to OG of 12v. On the tube socket pins I am getting the following readings: pin1 - 103.8v, pin4 - 0v, pin5 - 0v, pin6 - 103.9v

24v rail is working. pin4 and pin5 should raise a flag. You're getting 0v. You should be getting the proper heater voltage of whatever you have selected (~6.1v or ~12.5v). You say ICH has been replaced? Please probe the pins (very carefully), and if you can do it on the underside where you just touch the pads. Please list values relative to SG.

 

[holland]

I'm not sure why you are getting 2.6v out of ICE.

 

[holland]

^ regarding the 2.6v. From what I can tell, looking at the schematic, if all the transistors are working, you would need about 0.1v out of the opamp for the relay to actuate.

Try a new ICE. Any single JFET opamp will work.

Edit: 0.1v relative to VG, not SG.

Edit: *single* opamp, not dual, grr.

 

[arteom]

holland,

I am not sure how the pins are numbered on ICH, viewing it from the front the back pin is 33.2v, measuring from the bottom of the board that is all I get, the rest read at 0v. Measuring from the top of the board I get a reading of 12.5v out of the front left pin (viewed from the front). So I suppose that pin isnt connected all that well, I will have to solder it again. Would it work just as well if I were to drop a bit of solder on the top of the board instead of the back? Having a hard time getting the pins through the holes that had solder from the previous installation. Do you think this would lead to the problem with the ICE? I work at the ratshack, so will see if there are any single JFET opamps that I might be able to use.

I actually got to go to work right now, will connect from there and see what I can find.

p.s. when you say VG, would that be OG on this board? I get a reading of 9.4v on pin 6 in respect to OG. Oh and if anything I will replace Q4L and Q4R, on that set I was getting a reading of like 1.4v on one side and 0 on the other. I wasn't sure if they were blown or not.

 

[arteom]

Re-soldered the ICH, here are the readings I'm getting now:

pin1-12.5v, pin3-0v, pin5-0v
pin2-34.1v, pin4-1.2v

I am now getting 12.8 volts on pin4, 0v on pin5. I don't have h1 and h2 wired together, I had thought that it would be set to the 12v mode only if they were, shouldn't it be 6v on pin4? Still not getting a reading on pin5. No luck on the LED, going to replace Q4L and Q4R.

 

[arteom]

Wired everything up, everything hooked up using alligator clips bypassing volume control. There is sound!! The LED is still not lighting up but I think it may be blown/damaged, I will get a new LED. Hopefully the problem is a bad LED.

I would really like to thank everyone that helped me along, I would have been left clueless and deeply disappointed without you guys here, thanks for taking the time and laying everything down clearly.

Now, on to cleaning all this up and...casework.

 

[cfcubed]

Quote:

Originally Posted by arteom /img/forum/go_quote.gif Wired everything up, everything hooked up using alligator clips bypassing volume control. There is sound!! The LED is still not lighting up but I think it may be blown/damaged, I will get a new LED. Hopefully the problem is a bad LED.

Great! I assume your e12 relay is latching after 30 secs or so (hear the click).

If you can do so very carefully, you may wish to confirm the setup Vs about the board. I use masking tape on my DMM leads to leave only the tip of the probe exposed (to avoid shorts).

LEDs are available @ the shack & if they aren't the problem the LED circuit has few parts.

Bringing a "botched" CTH build to life is no small feat esp. for someone new to DIY... Sure this community came in to guide but you did the measuring & soldering. AFAIK even the small subset of CTHs that have had build problems have all been brought to life.

Seems although the CTH is considered an intermediate level project it is not beyond the reach of pretty much any determined DIYer. Part of the reason its a bit of a challenge is that it is effectively a full-featured desktop hybrid headamp in a 3"x5" space.

 

[adamus]

arteom, can you do me a favour and measure the voltage of pin 1 and 6 of the tube socket with respect to ground, with the tube in please.

 

[holland]

^Yes, please do. This is part of the setup steps, you need to complete it.

Sorry I didn't get back to you yesterday, haven't had the time.