Identifying Supplied Parts
- Thread starter JosephDuffy
- Start date
JosephDuffy
New member
Doc B. said:
Yep, it's pretty darn dead. Managed to knock the other one, too (though not as bad).
I've ordered 2 pairs so I've got a few shots at it, just in case I manage to mess up again. Hopefully not! Nothing else looks like it's been attacked with a soldering iron though so hopefully it'll be all good after I replace these
JosephDuffy
New member
Just to put my mind at rest for when they do arrive, I want to make sure I'm being safe/proper with my multimeter. I've got the black on COM port and red in the fused 600V port. The dial is set to the 600V DC setting. See photo for clarification.
I also want to get a crocodile clip for the sake of safety/keeping things easy for myself. I tried to make sure that they were rated for high enough voltage, and these ones on eBay look like they'd do the trick? I'm guessing it'd be better to have the clips on both leads so I can put the clips on both terminals and then move to look at the reading without worrying about knocking things/removing the probe from the terminal.
Again, thanks for everything. Can't wait to actually use the amp!
I also want to get a crocodile clip for the sake of safety/keeping things easy for myself. I tried to make sure that they were rated for high enough voltage, and these ones on eBay look like they'd do the trick? I'm guessing it'd be better to have the clips on both leads so I can put the clips on both terminals and then move to look at the reading without worrying about knocking things/removing the probe from the terminal.
Again, thanks for everything. Can't wait to actually use the amp!
Looks perfect!
The voltage rating on clip leads is going a little over the top, especially if you just use one on the ground lead.
The voltage rating on clip leads is going a little over the top, especially if you just use one on the ground lead.
JosephDuffy
New member
Sorry for surfacing an old thread, but I just recieved my capacitors and I wanted to double check they were correct. They look exactly the same, but the new one a little bit bigger, and has "France -12" rather than "France -13". I'm hoping the number is just the physical size, and I should be ok? I've tried taking some photos of them, but I can't get it to look clear without the flash, which means it's a little dark.
Here's the image
I'll solder the new ones on now (if not just for the practice
) and then I'll do my tests if it gets confirmed that these are the same/safe.
Thanks again for everyone's help!
Here's the image
I'll solder the new ones on now (if not just for the practice
) and then I'll do my tests if it gets confirmed that these are the same/safe.Thanks again for everyone's help!
That is the year they were made...
JosephDuffy
New member
Caucasian Blackplate said:
Well... now I feel silly! Just thought I'd check since the size was slightly off. Better be safe than sorry
But thanks
I gave it a Google but couldn't find any answers 
Grainger49
New member
I'm thinking that the 12 and 13 are date codes, machine codes or batch codes.
JosephDuffy
New member
I've soldered everything on, all my resistance/voltage checks, and they all came out fine. When I first did it I had a "deep hum" in the left channel, so I resoldered the pot and it went away. However, I still have a "buzzy hum", which stays fairly quiet when no audio source is connected, no matter how much I turn up the amp. However, when a source is connected, even without anything being connected at the other end of the cable, a hissing occurs and gets louder the more I turn the amp up (maybe this is just a cabling issue, though) Forgot I had another RCA cable to test. It was indeed a crappy RCA cable.
I know this should be a grounding issue, so I resoldered all the connections that I could see that are ground connections. I've double checked this, and made sure that all other joints are soldered. I must have missed a ground connection somewhere for this to still be happening. The main joint I'm worried about is the ground coming from the power transformer, since it has a lot of connections in one solder. However, I have resoldered this and it looks fine. I have included an image from the instructions, which has circled each of the joints I have resoldered. If I missed any or there's any more debugging I could be doing, please let me know.
I know this should be a grounding issue, so I resoldered all the connections that I could see that are ground connections. I've double checked this, and made sure that all other joints are soldered. I must have missed a ground connection somewhere for this to still be happening. The main joint I'm worried about is the ground coming from the power transformer, since it has a lot of connections in one solder. However, I have resoldered this and it looks fine. I have included an image from the instructions, which has circled each of the joints I have resoldered. If I missed any or there's any more debugging I could be doing, please let me know.
Grainger49
New member
The center lug on every terminal strip is ground as it is connected to the chassis. The bottom two terminal strips are used, maybe the two above the tube sockets too.
Check those and rewet them.
Check those and rewet them.
mcandmar
New member
Is the buzz only on one channel? If so swap the tubes around and see does it move, i've had a lot of bad luck with noisy tubes. And faint backround hum does seem to get better with time as things burn in.
As for solder points, check the middle post of the main power supply that connects to the transformer, i belive this is the center tap for the heater windings. And as Grainger says most of the middle posts are used as they are tied to the chassis. The final step i took which cured the hum on mine was to totally dismantle and rebuild the main power supply strip, something in that lot had a bad connection that re flowing didnt cure. I suspect it was far left post that is also connected to the bottom left corner of the transformer that was at fault. One other i completely missed was the small jumper wire from the headphone jack to the middle post of the bottom right strip. I fitted aftermarket sockets so i only skimmed through that section of the manual, hence i missed it initially.
Also try turning your soldering iron off while testing. I'm embarrassed to say this but i re-soldered my earth connections 2-3 times one night trying to cure a bzzzzt noise on one side, only to later find it went silent when i switched the soldering iron off :-[ ..much profanity ensued.
As for solder points, check the middle post of the main power supply that connects to the transformer, i belive this is the center tap for the heater windings. And as Grainger says most of the middle posts are used as they are tied to the chassis. The final step i took which cured the hum on mine was to totally dismantle and rebuild the main power supply strip, something in that lot had a bad connection that re flowing didnt cure. I suspect it was far left post that is also connected to the bottom left corner of the transformer that was at fault. One other i completely missed was the small jumper wire from the headphone jack to the middle post of the bottom right strip. I fitted aftermarket sockets so i only skimmed through that section of the manual, hence i missed it initially.
Also try turning your soldering iron off while testing. I'm embarrassed to say this but i re-soldered my earth connections 2-3 times one night trying to cure a bzzzzt noise on one side, only to later find it went silent when i switched the soldering iron off :-[ ..much profanity ensued.
JosephDuffy
New member
I'll check some more of the joints in a moment, but I think I resoldered the center joints.
I'd just like to add that the noise gets louder the longer the amp has been on, until about a minute in where it settles. I'm assuming this is still the ground (since the noise is in both channels), but I just thought I'd add that bit of information, just in case.
I'd just like to add that the noise gets louder the longer the amp has been on, until about a minute in where it settles. I'm assuming this is still the ground (since the noise is in both channels), but I just thought I'd add that bit of information, just in case.
mcandmar
New member
Hold on, has this amp only just been built and powered on for the first time? If its a loud bzzz that drowns out the music you have a problem, if its just a backround noise/hum then i wouldn't get overly worried about it until everything has had time to settle, especially the tubes. They do quieten down with a few days use, after about a week everything will be as quite as its going to get IMO.
For example one of my tubes got distinctly upset with me after being run upside down while testing, made all kinds of strange noises for a few power/heat cycles before it settled down again. I could hear its internals expanding as it heated up making a boing boing boing boing noise, eventually it made a loud POP and has been silent ever since. Got to love how they all have their own character ;D
Leave it playing for a few hours then listen again and see if it has changed..
For example one of my tubes got distinctly upset with me after being run upside down while testing, made all kinds of strange noises for a few power/heat cycles before it settled down again. I could hear its internals expanding as it heated up making a boing boing boing boing noise, eventually it made a loud POP and has been silent ever since. Got to love how they all have their own character ;D
Leave it playing for a few hours then listen again and see if it has changed..
JosephDuffy
New member
mcandmar said:
This makes sense. I do hear little rattles when I first turn it on/off, and since I'm awaiting a better RCA cable I'll give it a bit of use tonight and tomorrow and then see if the problem has subsided.
JosephDuffy
New member
Ok, bad sign: My fuse blew. I was using it last night for an hour or 2, then I turned it off for the night. I came to it now to use it and when I turned it on it didn't turn on at all, and the fuse in the amp is gone. I haven't changed anything and it was working fine last night. It's also plugged into a surge protector and no other fuses have blown. I'll have to buy some more fuses I guess!
Is there anything I can look at now so see why my fuse may have blown? I was still getting the buzzing last night, so it might be linked.
Is there anything I can look at now so see why my fuse may have blown? I was still getting the buzzing last night, so it might be linked.
mcandmar
New member
Very strange, by my half arsed calculations the load should only be a fraction of the 1amp rating of the fuse. i.e. a dead short or physical vibration are the only things that should break it. ...unless it was faulty all along and causing the buzzing
1amps are rare in this part of the world, most stuff is 3,5, or 13. You could try having a peek inside your multimeter if you want one in a hurry.
1amps are rare in this part of the world, most stuff is 3,5, or 13. You could try having a peek inside your multimeter if you want one in a hurry.
JosephDuffy
New member
mcandmar said:Very strange, by my half arsed calculations the load should only be a fraction of the 1amp rating of the fuse. i.e. a dead short or physical vibration are the only things that should break it. ...unless it was faulty all along and causing the buzzing
1amps are rare in this part of the world, most stuff is 3,5, or 13. You could try having a peek inside your multimeter if you want one in a hurry.
I just popped in to the market and a guy is selling some 1A fuses for 50p, but they're out of stock, so I'll have to go back on Friday when I'm not working. Maybe it was damaged (the US > UK trip is a long one), but I guess we'll see!
The fuse in my multimeter seems to have a 250mA fuse in it, but thanks for the idea!
JosephDuffy
New member
Doc B. said:
Just given these a double and triple check, along with any connections connected to them, and can't see any issues (joints look good, but might be worth resoldering them?)
