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Old 10th June 2010, 03:17 PM   #131
udailey is offline udailey  United States
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Quote:
Originally Posted by sabre66 View Post
Ok lets get back to this lm318 I seem to be having. The last picture shows the two lm318. Board on the left is with the ic that works the one on the right is the new one which matches the one that came with the package. The board on the right will just click on and off. If I swap the two ic's around the one on the left will now start to click on and off. Each board will power up one at a time if I only use the ic from the left hand board in picture 3.
Which is telling me that the new lm318 I got is also bad? So I bought 5 and all the new ones are bad? I doubt it, but have been wrong before Now it is hard to read the package on the left hand board but they are distinctively different in there markings. Are thes two different manufactures in here. Please Uriah send me one that looks like the left hand one

Also every one seems to think the sinks maybe too small if thats the case I'll get different ones But for now I may just put some fans on them.
Every LM318 I ordered was a Nat Semi. I had to order from no less than 4 different sources to get them all for some reason. Anyway, all Nat Semi. My LM318 look like your LEFT IC with only an etching in the surface and no silkscreen on the top like your RIGHT IC.
So from what you have said we can probably rule out a dead LM318 but we can rule IN that the proper LM318 will do the trick. I honestly wonder if the silkscreened one is a real Nat Semi chip. I know I sent it to you but obviously I am not in the fake IC business and obviously you have two supposedly Nat Semi ICs of which only one works.
Your other 5 that DONT work: Where did you get them from and do they look like the silkscreened one?
From what I remember from the previous buy and from earlier posts in the original thread a lot of people have had clicking trouble. I wonder if your home voltage is lower than normal and if for some reason its fine for the one IC and right there on the line of fine/not fine for the other ICs.
Troy I think you have helped a few people with this. Wasnt there a resistor that folks lowered the value of when they had the clicking trouble?
The sink is just way to small and the sinks on your Caddocks are going to let your Caddocks fry. This is basically a non starter. If you leave in those heatsinks they will fry if they have not already. Both the LM3886 and the Caddock but the Caddock first.
I also wonder where is the 470k resistor near the opamp on the left side. Maybe you mounted it below.
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Old 10th June 2010, 03:23 PM   #132
udailey is offline udailey  United States
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Forget my 470k remark. I saw your answer.
REGI, with the LDRs facing away from you the trimmer on the LEFT should be a 5k. Use the 5k pot here. 200r will still allow the board to work but you wont have balance control. 200R only belongs on the right hand side and it will allow balance control there for balancing minimum resistance of the shunt LDRs but will not effect the max resistance. The 5k has a large effect on the max resistance of the series so therefore you can have balance control.
Uriah
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Old 10th June 2010, 03:30 PM   #133
udailey is offline udailey  United States
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The ceramic caps in my hand have 100, 220, 221 on them. Two of them say K2J. I think that we have here 10pf, 22pf, 220pf. The 100 means 10 with zero zeros after it. So 10pf. 220 means 22 with zero zeros after it so 22pf. 221 means 22 with one zero after it so 220pf.
Uriah
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Old 10th June 2010, 03:51 PM   #134
AndrewT is offline AndrewT  Scotland
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Any idea what the K2 represents?
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Old 10th June 2010, 03:57 PM   #135
udailey is offline udailey  United States
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Something to do with Kemet.
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Old 10th June 2010, 04:04 PM   #136
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Originally Posted by udailey View Post
Forget my 470k remark. I saw your answer.
REGI, with the LDRs facing away from you the trimmer on the LEFT should be a 5k. Use the 5k pot here. 200r will still allow the board to work but you wont have balance control. 200R only belongs on the right hand side and it will allow balance control there for balancing minimum resistance of the shunt LDRs but will not effect the max resistance. The 5k has a large effect on the max resistance of the series so therefore you can have balance control.
Uriah
That will give you, not just a balance control, but a "panorama" control. I don't know the english word for that, but maybe you get the point. Nice explanation, now I get it. But I have to think if it is better to not implement it and assure a measured mathematically exact channel balance with the trimmers.

Could K2 be, like uriah proposes, some code for identifying it as a Kemet device?
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Old 10th June 2010, 04:05 PM   #137
udailey is offline udailey  United States
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Kemet, 200V, 5% = K2J
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Old 10th June 2010, 04:08 PM   #138
udailey is offline udailey  United States
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Originally Posted by regiregi22 View Post
That will give you, not just a balance control, but a "panorama" control. I don't know the english word for that, but maybe you get the point. Nice explanation, now I get it. But I have to think if it is better to not implement it and assure a measured mathematically exact channel balance with the trimmers.

Could K2 be, like uriah proposes, some code for identifying it as a Kemet device?
If you go for balance control using your DMM and not your ears you may be disappointed. Balance control is to help with the asymmetry of your system components and your room. I dont really care in my system if my left LDR is 1k more than my right LDR as long as that is the setting that properly centers the stereo image.
That last statement goes for the series LDRs. I prefer the Shunt to be balanced at min setting with the trimmer and DMM. After that I use my ear with the 5k.
Uriah
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Old 10th June 2010, 04:13 PM   #139
AndrewT is offline AndrewT  Scotland
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I prefer the Shunt to be balanced at min setting with the trimmer and DMM. After that I use my ear with the 5k.
Uriah
min setting = maximum attenuation = maximum shunt LDR resistance = maximum LED current = minimum in series LED resistance.
Can you confirm?
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Old 10th June 2010, 04:16 PM   #140
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Kemet, 200V, 5% = K2J
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