yet another meta42 problem thread
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New Head-Fier
Aug 16, 2002
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Aug 16, 2002
sorry if this has been asked or if similar stuff has come up, but i wasnt able to find exactly what i was looking for using search for some reason my service keeps going down so searches are not going well...if someone knows they've posted an answer to this before please let me know and i'll keep trying to find it.

well i finally got a free moment to finish up my amp. i've spent a good 2.5 months working a little at a time to get it done since i dont really ahve all that much time to work on it. (its a pretty ugly sight...but its the best i could do...i'm not very um adept at delicate work...) anyways so i finally get it to the point where i feel like i should give it some juice. i plug it in and the first thing i notice is that the led is on but very dim. so i unplug the power and start searching for the short after some searching i find that the only time this occurs is if the power ground is connected (i still dont know WHY this is happening but that its the power ground that is causing it) so i disconnect the power ground and try again this time the led only comes on when i turn the amp on not just if the power is connected. well after a few seconds of the amp turning on i realize that the buffer chips are getting so hot that i actually got a burn from one of them. actually thats how i realized that soemthign was wrong. anyways...i'm not sure if i may hve killed my buffers and/or my opamp...(how would i check this?) i do have a multimeter so my main question is what should be checking (i have version 1 of tangents board btw) i'm going to post a list of the parts i am currently using so that maybe i can get an idea as to what i might be doing wrong...i would post pics but someone is borrowing my digital camera for the next 3 months. here is the parts list: (to be used with some senn 580s)

Tangent's board ver. 1.0
opamp: AD823AN (a friend had a spare one so i'm using this as my test opamp and if i know everything works i'll swap in my AD8620)
buffers: EL2001cl (not stacked)
C1: jumpered
C2: 1000uF 16v panasonics
C3: 1000uF 16v panasonics
C4: wima 6.8uF 50v
C5: none
R1: 1.160k
R2: 1M
R3: 1.160k
R4: 10k
R5: 1.160k
R6: 100k
R7: 47ohm
R8/R9: jumpered
R10: jumpered
Q1/Q2: from tangent
D1: none
RLED: 4.75k
LED: blue Led (dont remember the specs)
Power: Elpac linear wal-wart +-12V
Input: gold RCA from parts express
output: Neutrick locking jack
POT: Alps Blue 100k
Case: Hammond Case

i followed Tangents tweak advice and i put in DIPs for all of the components and headers but had trouble finding the connectors for the headers. so i sort ripped some out of old computer cases (perhaps this was one of my problems?)

to be honest i dont have all that much time to trouble shoot this thing (i had time before but now i'm working random hours and tutoring and doing all kinds of stuff so i can start paying off my student loans come basically i've run out of purchasing funds for anymore parts. its kind of sad because what started out as a fun project is just giving me a massive migraine now. therefore to make things possibly a little easier on myself i set aside some extra cash...basically if you do not think that an easy (for me easy that is) solution can be worked out and think that perhaps you (that being a collective you to anyone interested) can trouble shoot and help me get to a working amp then i would be eternally grateful and of course would pay you for your troubles.
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