Tube Amp Archive

Gentlemen, I can't thank you enough! I have a working amp! Plenty of hum, some hiss...but I believe my 50% chance luck was good on the OT, as I've got no squeal. I put some cruddy tubes in the amp for start-up, so that may be contributing some to the noise. I'll try out some different pre-amp tubes ...

I'm wondering about that as well--here is a picture of the trimpot, perhaps someone will spot a wrong connection: [img:800:450]http://img.photobucket.com/albums/v519/mvonende/Express/20140426_100229_zpsd074d938.jpg[/img] It's a bit hard to see, but the arrow is pointing due north in this picture, an...

Okay, here we are! EDIT: I forgot to mention, these values are without the bulb limiter. Pin 1/8: 0 VDC for both V4 and V5 Pin 2 and 7: 3.42 VAC for V4 Pin 2 and 7: 3.43 VAC for V5 Pin 3: 417 VDC for both V4 and V5 Pin 4: 412 VDC for both V 4 and V5 Pin 5: -27.89 VDC for both V4 and V5 One thing I n...

I will measure and post voltages as soon as I get home, I appreciate all the help!

Thanks, gents! RJ, no worries--I appreciate all the help you've given with parts, advice, etc. MM, I've got a 40 watt bulb in the limiter and it's really bright--I'd say it's at full power with the EL34s in it. Did I make a simple rookie mistake by using too small a bulb? It was all I had on hand, b...

Thanks for the link to that picture! That's very helpful...I have a somewhat different version of PCB, but I think I'm following it. Here's where I'm different than the picture: I don't have the pair of black resistors shown from pin 1 (or eight) to ground. Are those 1 ohm 2 watt resistors? It's a b...

Sorry, double-post.

Hey all...after nearly two years, I've returned to finish this amp! For a number of reasons (none amp related :? ) I haven't been able to get to a place I could wrap this up. To pick up where I left off, I've gotten all of the components wired up and have done the "no tubes, light bulb limiter" powe...

This is very timely, I was just measuring out those leads as well and was planning on routing them under the board. I'll go over the top now. If you'd be so willing, I'd love a diagram showing the wiring--especially the standby switch, presence pot, and the 25w metal resistor most guys mount to the ...

Ok, thanks! I was hoping I'd read that correctly...

Just to double-check (before I cut them short)...the pair of yellow 300v secondary wires connect to the two solder points feeding the diode stack, correct?

Here's where I'm intending to connect them...

Hi all, after a bit of a delay, I'm back on track to finish up my PCB build...I have a couple of questions regarding the PT wiring... I'm using the Toneslut 11410 PT, so I have to connect the following color wires...here's how I'm planning on doing it: Black wires (120v, pair): one each to the power...

Thanks, guys! I appreciate the positive reinforcement...it really is an awesome way to learn. @Erik: I used the BOM (bill of materials) for a scratch build to source all my parts. The BOM, as well as scratch build layout, schematic, and the all-important build guide can be found here: https://tubeam...

Hey, thanks for the encouragement! I appreciate it...I can say that wiring heaters is my least favorite part of this build so far, lol... So here's the latest version...I'm cautiously optimistic with this one. I took my time and really made sure I got as close as possible before splitting the twists...

Thanks so much! That's an awesomely neat job of wiring, and one I will try to duplicate tonight. So clean...

Ok, I'll redo the wiring again. Edit--I guess I'm a bit confused. Page 28 on the guide shows the "lazy loop" method, not tightly twisted at all--in some cases, not twisted a bit. I can redo it mimicking that, but it seems to run counter to all the advice I've gotten in this thread? Am I better off u...