Lil' Knight
Headphoneus Supremus
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- Sep 16, 2007
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On the other side, does the solder touch the metal part of the pot?
Originally Posted by Lil' Knight /img/forum/go_quote.gif On the other side, does the solder touch the metal part of the pot? |
Originally Posted by Juaquin /img/forum/go_quote.gif The joints look ok, maybe a bit on the "cold" side (especially the ground ones). What kind of solder and iron are you using? |
Originally Posted by Juaquin /img/forum/go_quote.gif The solder is good - eutectic, which helps in preventing cold joints. The iron may not have enough power to heat the ground plane (wicks it away and dissipates it before the iron can catch up) - what wattage was the iron? |
19J6 => 12AU7 pin 1 => pin 6 pin 2 => pin 1 pin 3 => pin 4 pin 4 => pin 5 pin 5 => pin 2 pin 6 => pin 7 pin 7 => pin 3, pin 8 |
Originally Posted by Juaquin /img/forum/go_quote.gif 30W should be ok, just gotta let it work for a while (while being careful not to overheat the pot) |
Originally Posted by Narwhalius /img/forum/go_quote.gif I'll try again. Say I did successfully get all the joints soldered correctly, would there be any other major point that could cause this? Also, how do you know which component relates to left channel and right channel? So I could go through and make sure each left channel component is correctly soldered. |
Originally Posted by timmyGCSE /img/forum/go_quote.gif equalizer I'm having trouble with the tube pinout mappings from this picture: <snip> and your description: right, talking about the 12AU7 pinouts here - pin 1 => pin 2 - thats fine, pin 1 connects to pin 6 and they both go off to the 4-terminal, so in effect pins 1&2 on the 19J6 (this is how it looks..or is it going into 5 in which case I'm totally lost) pin 2 => pin 5 - also cool, this is in effect joining pin 5&6 from the 19J6 and taking it to the RCA's pin 3/8 => pin 7 - got it, in effect pin 7 from 19J6 with a 2K resistor to ground, clearly visible in pic. But then where's the cap come from that also looks like its soldered to pin 3?? pin 4 => pin 3 - now we get confused.. as per your pinout mappings, pin four should be pin 3 from the 19J6, which has the 150uF cap then to the 4-terminal ready for the output. but in your picture it shows as pin 4 going to ground!....which brings us to.. pin 5 => pin 4 - I expected this to go to ground since pin 4 on the 19J6 goes directly to ground.. but from the picture, well I'm not sure where that wire goes to! and then you have the 150uF cap into that pin as well..it looks to me as if that should be pin 3 of the 19J6 but ooh god I'm so confused... please help |
Originally Posted by tomb /img/forum/go_quote.gif You took some great pics awhile ago. Can you take a couple that show the entire PCB, top and bottom? Also, it would help to get a view of the wiring to the backplate and the terminal block at the pot. |
Originally Posted by timmyGCSE /img/forum/go_quote.gif equalizer I'm having trouble with the tube pinout mappings from this picture: |
Originally Posted by timmyGCSE /img/forum/go_quote.gif right, talking about the 12AU7 pinouts here - pin 1 => pin 2 - thats fine, pin 1 connects to pin 6 and they both go off to the 4-terminal, so in effect pins 1&2 on the 19J6 (this is how it looks..or is it going into 5 in which case I'm totally lost) |
Originally Posted by timmyGCSE /img/forum/go_quote.gif pin 2 => pin 5 - also cool, this is in effect joining pin 5&6 from the 19J6 and taking it to the RCA's |
Originally Posted by timmyGCSE /img/forum/go_quote.gif pin 3/8 => pin 7 - got it, in effect pin 7 from 19J6 with a 2K resistor to ground, clearly visible in pic. But then where's the cap come from that also looks like its soldered to pin 3?? |
Originally Posted by timmyGCSE /img/forum/go_quote.gif pin 4 => pin 3 - now we get confused.. as per your pinout mappings, pin four should be pin 3 from the 19J6, which has the 150uF cap then to the 4-terminal ready for the output. but in your picture it shows as pin 4 going to ground!....which brings us to.. pin 5 => pin 4 - I expected this to go to ground since pin 4 on the 19J6 goes directly to ground.. but from the picture, well I'm not sure where that wire goes to! and then you have the 150uF cap into that pin as well..it looks to me as if that should be pin 3 of the 19J6 but ooh god I'm so confused... |
Originally Posted by Juaquin /img/forum/go_quote.gif Some of those joints, particularly the ground ones, look cold. For example, in the third pic from the bottom, that joint in the middle. You can tell because it is not a smooth mound and doesn't look like it's all flowed together. If you want to be sure, grab the DMM and check the resistance between a lead that should be connected to ground, and a ground point elsewhere. It should be almost exactly 0 (less than an ohm, preferably lower). |