Welcome, Guest. Please Login or Register
Decware Audio Forums
08/21/14 at 09:13:55


Pages: 1
Send Topic Print
New here with a question (Read 1653 times)
KLP84
Verified Member
**




Posts: 7
New here with a question
03/07/12 at 22:37:26
 
Hello everybody,
    I just recently purchased and built the zkit1 amp and I have one problem. All of my test voltages are within spec except test points D. These points are testing at 3.3 and 3.6 volts. I will post exact numbers for all the test points in a few hours. Any help would be greatly appreciated.
    I do have a decent amount of experience with electronics but I still consider myself a novice and the is the first amp kit I've ever built. If I need to post a pic of the amp please let me know. Again any help is appreciated.
                                                                                          Thanks,
                                                                                            Kenny
Back to top
 
 
  IP Logged
KLP84
Verified Member
**




Posts: 7
Re: New here with a question
Reply #1 - 03/09/12 at 22:42:12
 
Well it took me a few days but I finally got a chance to retest and post my voltage measurements. Testing with a Fluke 115 meter my test voltages are
A: 356.3v
B: 307.5v
C: 12.3v
D (to pin 3): 3.3v
D (to pin 8): 3.6v
Again any helpful input is greatly appreciated.
Back to top
 
 
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 2379
Re: New here with a question
Reply #2 - 03/11/12 at 20:03:17
 
What input tube are you using?

Back to top
 
 
WWW   IP Logged
KLP84
Verified Member
**




Posts: 7
Re: New here with a question
Reply #3 - 03/11/12 at 22:03:42
 
I am using the JJ e88cc/6922
Back to top
 
 
  IP Logged
KLP84
Verified Member
**




Posts: 7
Re: New here with a question
Reply #4 - 03/15/12 at 18:35:25
 
Any ideas? I'm very anxious to hear the amp but I want to make sure everything is right before I actually use it.
Back to top
 
 
  IP Logged
KLP84
Verified Member
**




Posts: 7
Re: New here with a question
Reply #5 - 03/20/12 at 18:30:45
 
Steve,
     Please forgive me for not noticing the post about your father before now. I am truly sorry for your loss. I certainly understand now why it may take you some time to reply to my post. You have my condolence for your loss.  I look forward to hearing from you.
Sincerely,
Kenny
Back to top
 
 
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 2379
Re: New here with a question
Reply #6 - 03/21/12 at 16:46:18
 
Thanks, the voltages on pins 3 and 8 (cathodes) of the input tube are too high.  I assume that the amp works but is sonically "thin" sounding and has less gain that it should.  The obvious thing is to check the values of the resistors on those pins, as well as the values of the plate resistors (pins 1 and 6) to be sure they are the correct value.

Steve

Back to top
 
 
WWW   IP Logged
KLP84
Verified Member
**




Posts: 7
Re: New here with a question
Reply #7 - 03/24/12 at 02:49:22
 
Ok, I have checked all the resistors in the amp and all are within tolerance. So as of right now I am still stumped.  What is my next step now? Oh and I also checked voltage into the 1k6w resistor which is at 446v. Isn't that higher then what it should be?
Thanks,
Kenny
Back to top
 
« Last Edit: 03/24/12 at 03:30:37 by KLP84 »  
  IP Logged
KLP84
Verified Member
**




Posts: 7
Re: New here with a question
Reply #8 - 04/07/12 at 02:27:08
 
OK I went ahead and hooked my iPod up to the amp today and it sounds great. I did replace the 47k resistors with some that measured closer to spec and this brought test point D to the very high end of the allowance. The amp sounds fantastic. I would still like to see if I can get the amp closer to ideal and I am still a little confused as to what is possibly causing this problem. Any more help is greatly appreciated.
Back to top
 
 
  IP Logged
Pages: 1
Send Topic Print