Hummm ... If it's the power transformer, then now what?

Added: 2026-05-10

[00:00:05]I'm live.

[00:00:07]Hey y'all.

[00:00:12]Got to fix this thing.

[00:00:14]Going to have to move that power transformer. That's all there is to it.

[00:00:20]Just couldn't just couldn't deal with deal with it last night. So that's the task tonight. I got to mess with that transformer.

[00:00:29]Gotta yeah get it get back in get back in there up to my elbows and hardware moving stuff around. So join me will you?

[00:00:44]There we go. There it is.

[00:00:49]this framed.

[00:01:00]All right.

[00:01:04]So, the story so far, if you're not nice tubes in it, I thought I mean, at least these reflectors. These are like the Soviet reflector uh substitutes for EL84s.

[00:01:18]uh has six CG7s.

[00:01:20]Nice tube.

[00:01:22]Um the P the output transformers, nothing to write home about. I been wanting to use these output transformers. I was thinking that what I would would have made with these and what I was thinking of making with this was a clone of my Beaver Valley.

[00:01:42]Decided, hey, what the hell? Let me stick with these six CG7s. That should be interesting.

[00:01:48]And uh, of course, the original circuit wasn't behaving itself, wasn't giving me any wasn't giving me any gain really.

[00:02:02]And I figured that um you know I could mess around with the circuit as it was, but that um trying to get back trying to get the uh the stream up on my uh computer here.

[00:02:26]uh you know it was going to be almost as hard to go in and you know find resistors that had drifted and might be responsible for the gain issue and even then I wasn't going to get all that much gain that circuit just wasn't going to you know these are medium mu triodes there it's it's kind of tough so I went with a different circuit rebuilt gutted the whole thing rebuilt from scratch and one of the things I did was well These original output transformers had been right here and then the power transformer which is now here was over here. Well, to put in, you know, to put in these big output transformers, I needed to move the power transformer and I moved it over here.

[00:03:22]That may have been a really bad idea because now I'm getting a hum and um that hum is has been resistant to uh to finding a way to get rid of it.

[00:03:42]So that's the task is to get rid of that hum. I thought I might be able to do it last night. I tried a few things. U well, mainly all I was able to get to last night was u twisting some leads off the power transformer that had not been twisted before and that didn't have any effect.

[00:04:11]um somewhere in there that the hum decreased in magnitude in one channel uh but not less than it had been in the other. I mean, you know, now it's like the same hum in both channels. I don't know why. Maybe from moving maybe maybe some of that shifting around of components did a little bit of something.

[00:04:34]Anyway, so hello true voice of reason. Good evening to you as well.

[00:04:43]And um yeah, just got to get to it. So I got take the tubes out um and then got to unbolt the unbolt this and then see what I can find out.

[00:05:03]You know, one idea is once I get it unbolted, maybe then I put the tubes back in and just see whether uh moving, rotating the power transformer has any kind of effect.

[00:05:22]Framing isn't quite right, is it?

[00:05:27]I bet I know why.

[00:05:29]I don't know if I know why.

[00:05:44]Hello, Patrick.

[00:05:47]All right, so let's do it.

[00:06:33]So, I'm watching to see whether the uh whether I managed to fix the framing because uh y'all are the video's lagged quite a ways.

[00:06:49]Oh my, that was a that's an interesting comment, TVR.

[00:06:56]All right.

[00:06:57]I just I I can't I I just can't uh encourage that sort of puntery or whatever.

[00:07:06]Um yeah.

[00:07:09]Oh [ __ ] I laughed.

[00:07:12]All right, scoot her over.

[00:07:18]This is going to be a bit pain which is I mean essentially to get it out and we probably have to move the choke as well you know but you know so that's when I was contemplating doing it last night I was just like I was just blah blah blah blah all sorts of things that I need to do to in order to even get to it. Uh, this will this needs to be popped out in order to get to uh one of the bolts, nuts, whatever.

[00:07:51]And there.

[00:07:56]Oh, great. So, that's going to um mean liberating this uh terminal strip.

[00:08:05]That's too bad.

[00:08:07]And then there's one back there. And then one right under the choke. So I'm gonna get that off.

[00:08:17]Okay. Where's the narwhal?

[00:08:32]Narwhal.

[00:08:42]There it is.

[00:09:32]So, if you were with me last night, you know I played just like a little bit of music course that got nailed for copyright.

[00:09:40]decad to go back and trim the music out of the, you know, so it won't get completely demonetized and whatnot.

[00:09:54]Not that I make a whole lot of money off of this stuff, but Oh yeah, by the way, I'm supposed to mention these sorts of things for my own good. Uh, super chats are a thing. Don't feel obliged.

[00:10:07]However, they are a thing. All right.

[00:10:11]Not just the best screwdriver for this big long temporary leads. I don't know. I I hadn't really thought that far ahead to be perfectly honest.

[00:10:49]Um, you know, it's probably not a bad idea, but uh yeah, I don't know.

[00:10:57]I was thinking more just um for now just seeing if rotating it would do anything.

[00:11:08]And then, you know, once I got it sort of off the once I've actually got it unbolted, then I can be a little more considered, I suppose.

[00:11:23]Where's the washer?

[00:12:10]Don't know twisting these leads have any substantial effect.

[00:12:17]And you know, it's even possible that moving the choke could do something, but I uh actually no, I'm pretty sure that wouldn't don't think unless the choke I don't know the choke should have 120 in it, not 60. Um, that was hard to hard to for sure rule out anything, but physics is still physics.

[00:12:56]Guess [clears throat] I didn't have that washer in.

[00:13:05]All righty.

[00:13:11]The other thing I've been thinking about is that I've got these gaping holes where the original multicaps were and wondering whether that could be a problem in that, you know, I've got holes where there weren't holes before and maybe EMI is getting through those somehow. I I don't know. Um, it'd been nice maybe to close those. On the other hand, you know, having having holes in the chassis does at least u uh mitigate heat issues. So, if it's not the problem, then I don't want to mess with it.

[00:14:05]Go get some popcorn. Yes, indeed.

[00:14:13]Yeah, but there's not a whole lot of room uh for moving the transformer with these leads, is there?

[00:14:21]Um, and I'll have to obviously rotate it around that hole there rather than rotate it around its central axis. But anyway, that's that's that's what whatever whatever.

[00:14:40]It's a big whatever.

[00:15:24]Yeah, the the music sounded good.

[00:15:28]It was a little seemed a little bass heavy, but then that is a super bass heavy track anyway, so maybe that's just it. I think I've noticed it sounding awfully bass heavy through those speakers anyway.

[00:15:43]Um, I you know I have to remember that back in the day when I was listening to that a lot. I didn't have those JBL's that's for sure.

[00:16:36]But but you know, Bob, you are on point that um if I'm going to see whether anything but rotation might solve the issue that I will need to put on new leads.

[00:16:54]Uh yeah, not looking forward to that.

[00:17:22]I mean, I guess, you know, to be perfectly honest, I'm feeling a little bit of a like a little bit of a bonehead for putting the power transformer where I did.

[00:17:32]And um yeah, whatever though, you know, there it's just I look at it and I go, I don't know where else to put the damn thing.

[00:17:51]So, if some kind of minor adjustment doesn't work, then I don't know what to do really. Um, I mean, I guess I could go back to the original output transformers and just never mind the idea of uh, yeah, anyway, never mind the idea of using these transformers that I wanted to use, etc. Never mind the idea of making this a truly special sort of amp rather than Yeah. Okay.

[00:18:31]modified a console.

[00:18:34]Good for you.

[00:18:38]It's hard to let go.

[00:18:56]nice of you to drop in TVR if you haven't left already.

[00:19:02]I realize the time thing in the those of you in Eastern time zone is or wherever you are.

[00:19:54]the uh lucky man. It's um it's true. People do get super dogmatic about component placement, hardware, etc. wiring and all that. And and you know, there is a reason for it like you said, like you noted. Um, you know, it doesn't always mean that they're up that the people who are screaming a certain thing and are exactly right, but they do have a point in that these things can be awfully pnicity.

[00:20:37]There's washer Trying to keep all my hardware bundled here.

[00:21:22]These are number four hardware. They're kind of tiny.

[00:21:40]This is kind of buming me out, I guess.

[00:21:42]Yeah, I'll just have to um bolt it back in place once I get the transformer free. I'll just put the bolt back so that I so that's fastened down.

[00:21:59]This is the trickiest of the bolts, of course.

[00:23:15]Also trying to be mindful of not completely destroying my paint job in this process.

[00:24:38]Probably should have done this already, but I want to put this choke back on so it's not just flapping in a breeze.

[00:25:12]So, yes, I'm holding the transformer on, but the transformer is kind of holding itself there because of the the wires sticking through the hole.

[00:25:25]And I've reinforced those with a couple at least a couple layers of shrink tubing.

[00:25:33]So they've got some integrity and ability to hold up.

[00:25:40]But I am still of course holding it with one finger.

[00:25:51]Should just let it go.

[00:26:20]Jesus.

[00:26:36]Got a couple of wooden blocks there to hold the transformer up. And I'm like, "Oh [ __ ] where's the trans where's the screwdriver?" And of course, where's the one place it is? It's like sticking underneath one of the blocks. Wait. All right.

[00:26:51]This one here can 850.

[00:27:32]Jesus age, dog.

[00:27:37]Excuse my uh [clears throat] I don't know how much I can be able to rotate this.

[00:28:18]I guess that's enough at least to see whether whether rotating it does anything if it needs to be actually physically moved.

[00:28:29]Uh going to have to I know that wasn't intelligible.

[00:28:57]Oh, [ __ ] Yeah, I was gonna freaking the the thing.

[00:29:09]Does it matter?

[00:29:13]I think it's kind of So, there's a terminal strip in there that's held down by one of the bolts that was also holding down the power transformer.

[00:29:23]And I'm like, "Ah crap, I forgot about that."

[00:29:26]But I think it's pretty much holding its place with just the fact that all there's all other all sorts of stuff connected to it.

[00:29:40]Knock wood and all that choke.

[00:30:08]All right, just checking that I can do this before I put stuff in.

[00:30:58]God damn it.

[00:31:02][snorts] Oh boy, that was scary.

[00:31:23]I've never done that.

[00:31:36]Want to do that too many times for sure.

[00:32:13]connector up.

[00:34:42]Y'all ready for this?

[00:34:56]Something bad happened.

[00:35:07]There was a an extra [clears throat] bit of alarming hum.

[00:35:20]And um h so I'm thinking I better check underneath to make sure uh you know for example that terminal strip may just need to be may just need to go ahead and f fasten that down so nothing awful happens and hope nothing awful did happen All right.

[00:35:54]He's taking everything back up.

[00:37:08]Stick a fat nut bolt in here to hold this down while I go underneath.

[00:38:52]This is simple.

[00:39:00]Got to rotate. Get this out of the way.

[00:40:24]These tweezers are awesome. They're non-magnetic.

[00:40:30]Sometimes you really need that.

[00:40:34]Sometimes it's nice to have magnetic tweezers. Other times a total pain.

[00:41:07]That work it Oh jeez. What the [ __ ] lock washer just disappeared.

[00:41:36]Where should it go? Where is it? Where is it? The lock washer.

[00:41:43]washer. Jesus Christ.

[00:42:05]Where is that?

[00:42:11]I mean, come on.

[00:42:25]It's the sort of thing that just washer just vaporized.

[00:42:38]This is gone.

[00:43:01]O, it's gone.

[00:43:07]just disappeared.

[00:43:38]I mean, come on.

[00:43:43]Where did it go?

[00:43:49]Are you freaking serious?

[00:44:12]Oh, there it is.

[00:44:14]Why did it stick there?

[00:44:20]So weird.

[00:44:45]Getting these little buggers on is um interesting.

[00:45:14]Second try, y'all.

[00:46:08]Okay, I better just look and make sure nothing screw is going on.

[00:46:16]Need to worry about that choke. I don't know. Maybe not. I think I will go ahead and bolt it down.

[00:47:01]That was stupid.

[00:49:21]Well, nothing to do about it but try again. I think don't see anything wrong that would lead to the strangeness.

[00:51:25]Have fun. Lucky.

[00:53:07]What happened?

[00:53:18]Oh, you know what? I wonder if I blew a fuse.

[00:53:57]Yep.

[00:54:00]I guess that's what they're for.

[00:54:28]two fuse.

[00:54:31]Don't like to be blowing those, but it's better than frying other stuff. There is maybe I'll use one of my cheaper fuses for interesting purposes.

[00:55:18]backwards.

[00:55:32]Let's hope that doesn't happen again.

[00:56:05]The rectifier is not uh not heating.

[00:57:05]Oh, that could be bad. That could be very bad. I hope it's not very bad.

[00:57:12]So, um, what I'm muttering about is I turn it on and the all the other heaters came up that the rectifier didn't heat up.

[00:57:22]And, uh, of course, you know, I had a short circuit that blew a fuse.

[00:57:32]What if it was the 5V filament supply that shorted blew a fuse, but maybe it maybe it fried the windings also. I don't know. I mean, just kind of guessing, thinking of worst cases.

[00:59:43]I'm just trying to think how I might um how I might try to see what the problem is and whether thinking about whether it'd be a good idea to plug it in with no tubes attached.

[01:00:05]Um because then at least I could check uh voltages on the various windings.

[01:00:18]Dang. Is this Hold on.

[01:00:36]If I'm going to do that without any tubes, I could just turn it all the way over and then I don't have to worry about this transformer falling off. And I can show you what I'm doing.

[01:00:50]So, let's see.

[01:01:09]All right. So, what happened? The um rectifier tube was not heating up, which I mean I don't know what that what to infer.

[01:01:26]Um, you know, did the did it just suddenly go bad? I mean, I don't that's not really the kind of thing that happens to rectifier tubes, I don't think.

[01:01:45]Um, but anyway, if I turn it on, let me think about this.

[01:01:59]Um, should be able to see what the voltage on the um, I should be able to see what the voltage coming up on all the windings is.

[01:02:15]Um yeah, I think just trying to think if this might be a very bad idea.

[01:02:42]Yeah, I mean Edor makes nice transformers. I'm not sure what the what the thing you're suggesting is um because I mean unless I literally just fried my power transformer, but um problem doesn't appear to be transformers. uh except placement maybe probably I don't know I'm just trying to think like what might have happened anyway Um, click leads.

[01:03:48]What do you mean?

[01:03:51]You mean cut?

[01:04:12]Yeah, I'm just trying to No, it's a it's a 54GB testing hot.

[01:04:28]If I don't have any I mean these these are just essentially dead ends without the rectifier in place.

[01:04:39]Um, oh, you mean like go ahead and clip in my probes or at least one of them.

[01:05:00]Still not sure entirely sure what you [snorts] mean.

[01:05:59]Oh, but I can't uh test this thing getting in. Maybe maybe want to check that AC voltage then.

[01:06:15]Maybe clip in instead.

[01:06:39]I mean, I'm just Yeah, because I'm I'm just wanting to see if um if there's 5 volts on that when I turn it on.

[01:07:21]So secure, it Oh jeez, that's not good.

[01:07:57]Oh crap.

[01:08:03]Better test the other filaments as well, the other um linings.

[01:09:00]That's very bad.

[01:09:06]I just tried that transformer.

[01:09:14]Guess I'm just doing this wrong. It's volt AC.

[01:10:13]I blow the fuse again.

[01:10:16]Nothing's registering.

[01:10:22]There's nothing Oh boy.

[01:11:40]All right. So, if you weren't following what was happening there, I was checking the voltages on the various secondaries of the transformer and I was getting essentially no voltage on anything.

[01:11:55]which doesn't make a lot of sense because at least before the heaters for the other the six-volt supplies the six-volt tubes were were were lighting up and um suggesting that it's just not getting any power at all. I mean, I guess I could have checked the um primary. Just go ahead and check this fuse, I guess. See if I That doesn't make sense either.

[01:12:50]Looks like it's Gonzo.

[01:13:03]Yeah. Blown blown blown.

[01:13:06]Like thing's just gone.

[01:13:15]Jeez Louise.

[01:13:52]God damn, man. This sucks. This really sucks. This is blowing fuses.

[01:13:58]She was blowing fuses with tubes in the hell did I do?

[01:14:42]Yeah, these things are scary sometimes.

[01:14:45]Damn it.

[01:15:04]I can't go turning it on again. At least not with tubes in.

[01:15:27]All right. So, what I don't know, well, what I do know is it blew a fuse.

[01:15:33]I know that the rectifier tube did not heat up.

[01:15:44]And it suggests to me that perhaps there's a short in the five filament 5V filament supply maybe or I don't know or what. Um, appears it appeared that the other filaments did heat, did light, they were glowing.

[01:16:13]And then I turned it off, but I don't know when the fuse blew.

[01:16:25]like so this time, you know, unplugged all the tubes and turned it on to check voltages and I got nothing because it was a blown fuse. Now the question is, did the fuse blow like because I turned it on with nothing with no tubes in there or did it turn on? Did it the or did the fuse blow while I still had all the tubes in there? It's just the filaments were got hot enough to glow, but I couldn't tell exactly when the fuse like when power was actually cut because you know once they're hot they didn't immediately why would it short Because All right. Well, put [clears throat] in there. We're going to the dim this time.

[01:18:01]That might keep if there is a short even without the tubes in that might keep the fuse from blowing and give me time to figure out what's going on.

[01:18:17]Plus, if the fuse does blow while the light bulbs in there on, then I'll see it right away because the light bulb will just turn off immediately.

[01:19:02]All right, looks like I'm going to need to order some more 2 amp fuses.

[01:19:52]And I was thinking what I expect with the dim bulb is that the bulb will be dim. Like won't like really light up at I mean, it really shouldn't be drawing any current at all with no tubes in at least. I mean, am I am I forgetting?

[01:20:22]I mean, maybe crosses 100.

[01:20:26]Not even. Wait.

[01:20:34]draw draw a bit across that cathode. Um those 100 ohm resistors to the cathode and then through the through the cathode resistor.

[01:20:52]But that shouldn't be much. It's just six volts. anything.

[01:21:01]All right.

[01:22:24]So, I'm just trying to look for any obvious badness that Um, okay, let's try it.

[01:23:21]Okay, bulb is dim.

[01:23:26]Not sure it's even as dim as I would expect it to be, but it is dim.

[01:23:35]All right. 5 volts.

[01:24:05]So, it was not heating up because there was a short somewhere else.

[01:24:12]Probably already blown the fuse.

[01:24:16]Let's check six volt supply.

[01:24:38]Well, 6.4.

[01:24:50]Check the high voltage secondary.

[01:25:01]597 volts.

[01:25:11]All right, transformer is fine.

[01:25:15]Something else is not.

[01:25:19]God damn it.

[01:25:37]Well, another dramatic day in the life, huh? I um It's almost 10:30 here. I think this is the sort of thing that uh that I shouldn't be doing at this hour.

[01:25:56]It's clearly something really messed up going on and just not feeling like I've got the energy to figure it out tonight. So, I think I'm going to have to call it a night.

[01:26:15]Well, sorry I didn't figure the dang thing out.

[01:26:22]Jeez, man. It's, you know.

[01:26:26]Jeez.

[01:26:33]I mean, I'm just looking. I don't see anything why it would be why it would be shorting, but All right. Anyway, guys, I think I'm going to go. Appreciate you tuning in and uh witnessing this particular disaster of diagnostic diagnostics disaster shenanigans.

[01:27:22]I was hoping we'd have some fun.

[01:27:25]This was not too much fun.

[01:27:28]Bummer, huh?

[01:27:30]All right, guys.

[01:27:36]Did you?

[01:27:39]Yeah, I know, Bob. Right. Better luck next time.

[01:27:44]Easy come easy goes and all that.

[01:27:53]Cheers, guys.