Have no filament voltage for my champ amp?

[Dennis Perusse]

**********Update****Here's a muppet news flash*****************


Okay, here is an update with a happy ending involved. Where it's been over a month since I last posted I figured that I'd post some good news. Taking CoolBlueGlow's advice I abandoned the PT that I was using. I started looking through my stash of PT's and I found another Champ amp Transformer. The PT number is 40-18027 and it is the one used for either 120 or 240v operation. I actually forgot that I had that in my stash and I knew that it worked so I got around to redoing the wiring, again, and this time I'd do it completely differently from before.
Now differently, to me, meant that no eyelet board nor turret board would be used. I instead did it with terminal strips and even though it has that rat's nest look I figured that for my first build I'd find it acceptable. Plus my eyelet board looked so haggard I felt that terminal strips can't be nearly as bad. It took me many nights of checking, rechecking, and scratching my head until searches on this site showed me the answers that I needed to get the wiring correct. I do have to say that it was much easier for me to do it this way than the eyelet board but if I ever do another amp like this I will never do it the way I did this one. For any newbie builders like myself the old adage is true, "cleanliness is next to godliness". Take the time in your builds to see where your wires are going an problems will melt away as then you've taken account for everything important. I didn't and got myself into trouble more times than I can shake a stick at. I know better now and my next build will be much better as I'll know what not to do.
Carrying on here, this morning, my brother came down to visit. He's also into tube amps but I got mine done first and I wanted him to experience the joy or the failure of my project. With guitar plugged in, once the tubes warmed up he started strumming away and was completely surprised as much as I was as the sounds that came out of the thing. I never realized how much 5 watts of sound can be but both of us were pleased as the results. It worked perfectly, yes a little bit of hum but for a Single Ended amp and my first one I could care less.
I am very happy and just wanted to thank everyone on this forum for all of the help and advice. I can't wait to make a marshall amp although not too sure which way I want to go with it. I know it's gonna be a head but not sure if I want to do an 18watt or not. I will do it with a kit instead of sourcing my parts out just so that it happens faster than the amount of time taken on this project. In either event I can't complain, my goal was to learn how to build an amp and I did just that. Now onto the next project of fixing my brother's Radio Shack Boston monoblock before the next guitar tube amp project.


Dennis

ps Oh btw, in the pics the cab is just painted with ebony stain. There is no tolex on it at all. The Rectifier tube is an RCA Nos 5y3, the power tube is a Sovtek 6V6 and the preamp tube is also a Sovtek 12ax7. Just have to relearn my six string again and I'm gonna be quite happy with everything.
My apologies if any of the pics are a bit dark, the cell phone camera isn't as good as my regular digital one.

 

[Wally]

Kudos on getting the amp working, Dennis. However, you have a PT sitting there in unknown condition, right? Imho and ime, it is best to fully ascertain the condition of a part before taking it out of the circuit. IT may well be that the problem you were having was not centered in that PT and that you have abandoned a perfectly good PT. When it was mentioned earlier in this thread that your heater filament voltage problem might be a shorted filament, that poster was meaning that you might have had a bad tube or a bad wiring situation that was causing the problem.
Regarding the hum in this amp.....in a way, I relate your thoughts toward this hum problem to the lack of heater filmament voltage in the other iteration of this map. That is, imho, that hum is a problem; and it is being ignored. There is no good reason why that amp cannot be a quiet amp. Finding the cause of that hum....just as finding the true cause of the lack of heater filament voltage....would be an educational experience. We learn more by dealing with adversisty/challenge than we do by taking the easy path. Just a thought......

 

[guitarzan13]

NM.... Read your update

 

[andyfromdenver]

Glad it's working!
I like that color combo; Looks sharp $$

 

[muchxs]

Glad it's working!
I like that color combo; Looks sharp $$

That's the way Fender did 'em in '64.

 

[Wally]

Painting the baffleboard black would make it look closer to the Fender thing....
but I kind of like the peek-a-boo look of the natural baffleboard. It shows off the speaker.

 

[Dennis Perusse]

Hello,


Yeah it's true that a lot of things could have been wrong with how I had the amp wired. I also put in a nos rectifier tube as I've heard that the new 5y3's push more voltage than the original ones do. This, the wiring, was what made me decide to use terminal strips where my eyelet board looked horrid. Plus the hum is only when the guitar isn't connected to the amp. Seems rather quiet to me when my brother was playing the guitar on it.
Eventually I do plan on sorting out the hum although for right now I just want to enjoy the feeling of accomplishment of getting the project done. I can also guarantee that if I show the picture of the internals experienced builders will either laugh or groan. ;-)
As for my previous PT, yeah I still plan on sorting that out properly. It just was easier to use the other PT since I knew that that worked. Once I find out what is the issue with the other PT then I'll probably use it in another project. Nothing wrong with two champ amps you know, and hopefully a 5c1 should I get the opportunity. I would like to do Kalamazoo Model 2 amp but if I did then I'd do it in a fender chassis with twin speakers. I recently did a layout for the Model 1 but haven't yet done one for a Model 2. Dang this hobby is addicting!

One thing that I will do should I do another tweed circuit is the following;

1. Never do it using terminal strips again. I'm just not that good yet of making it all look clean and perfect. I'd rather try out either tag board or turret board next time.

2. Never use a tweed chassis again. It's tough to get in there without a lot of planning so I'd rather use a silverface chassis or blackface style of chassis. Plenty of room to route wiring hopefully causing fewer problems along the way.

3. Take more time and get equipment savvy. I still need to get my VTVM together and get comfortable with it. Plus my modern DMM I should be more knowledgeable so not to make mistakes that most newbies do. Plus their are other tools I wish to acquire when I continue on to the next build. Let's not forget getting more books too. I love to read about this stuff and more is always better.

4. Use one style of layout. I used both Triode Electronics champ layout as well as Webers 5f1 layout. Sometimes it can make more sense to just use one and not second guess myself and follow it slowly but with confidence.

All in all I'm having a blast and can't thank everyone enough for the joy that I have found.

Dennis

 

[muchxs]

One thing that I will do should I do another tweed circuit is the following;

1. Never do it using terminal strips again. I'm just not that good yet of making it all look clean and perfect. I'd rather try out either tag board or turret board next time.

2. Never use a tweed chassis again. It's tough to get in there without a lot of planning so I'd rather use a silverface chassis or blackface style of chassis. Plenty of room to route wiring hopefully causing fewer problems along the way.

Wait! That's two things.

I expect youd like tweeds more if you didn't start with a "ship in a bottle" 5F1. The circuit board is usually pre-wired with flying leads and then dropped in. Some guys even wire the controls in a jig then load them pre- assembled.

The terminal strips aren't a bad idea. You had lots of practice soldering things in a tight space without cooking adjacent parts and wires.

Remember... less wire is better. Just because you have more room doesn't mean you should use more wire.

Just because less wire is better doesn't mean I don't leave a lot of wire on my transformer leads. I never know when I'm going to change my mind and re-use a transformer for another project.

 

[Dennis Perusse]

In an of itself the tweed circuit is okay. For me their just isn't enough room for my liking. Now to do the same circuit using a silverface chassis, to me that would be ideal although I wonder what it would look like using a silver/blackface chassis and cab with tweed on it? Hmmm.

 

[muchxs]

In an of itself the tweed circuit is okay. For me their just isn't enough room for my liking. Now to do the same circuit using a silverface chassis, to me that would be ideal although I wonder what it would look like using a silver/blackface chassis and cab with tweed on it? Hmmm.

It would look like a Kendrick.

Look at a '60s Champ circuit board. It's easy to see the underlying "tweed" circuit.

 

[Dennis Perusse]

Muchxs,

I never thought about that. Yeah it would look like a Kendrick amp. As for the circuit though, yes I can see the "tweed circuit". Having said this my comfort level with the tweed chassis versus the blackface/silverface chassis is quite stark. I like the later chassis better than the earlier ones. Their is just more room to get at stuff than the earlier chassis. Plus I'm also not quite adept as yet of figuring out how the wires would interact with one another. I'm sure their are other posts where people are gonna be concerned about packing the circuit into the chassis. Where I've rewired that amp six ways to Sunday my thoughts about using a tweed chassis again might be construed as gun shy. Then again this is also my first amp and it is just a first impression.
It would be cool, if I get around to doing another tweed circuit would be to put it into a later chassis/style of amp. For me that is a better preference than the earlier champ chassis. Having said that I probably shouldn't pass judgement until I use a different wiring scheme (i.e. turret board or tag board) but my initial feelings are that a later chassis would be easier to enjoy. Better yet I probably should use some type of prototyping method to see which chassis style would be worth putting it together. But then again that's for another project down the road although I really do appreciate all the views presented.
Slightly off topic last night I tried to start work on creating a layout for a Kalamazoo Model 2 in a layout form. No one has done this yet and posted it on this forum. I did a layout for the Model one and posted it but I want to try my hand at a model 2 as one day I'd like to clone it but using a different chassis/cab combo.

 

[muchxs]

Kalamazoo Model 2:

Tweed Princeton meets Vibro Champ. No grid leak on V1, 6BQ5 instead of 6V6, simplified trem with no depth control.

That's a circuit that would go in a BF Champ or Vibro Champ chassis with room to spare.