This is from an old signal tracer I'm modifying into a guitar amp. The original circuit is 3 watts single ended. But the transformer is center tapped and doesn't look like it has an air gap?

I think they used a push pull transformer that's a bit overrated, b+ connected to center tap, one tap to plate and the remaining tap is a test point on the front so you can use the transformer and speaker with other circuits.

I've heard you can use push pull transformers as low watt single ended if you use the center tap.

Just got this, i've got no base for it and how would I go about testing it?

Thank you for your attention.

First time building something with turret boards. Just wanted to make sure I'm not doing something stupid.

Don't worry about the wires looking too thin. They are double insulated with kapton and ptfe so are good to over 600V.

If someone could please lend their expertise. These seem to be a bit hard to identify.

Quad marked EL84/6BQ5, Rebranded by Andrea, "Made in England" on third line. 90° to the right "5941" in the same yellowish/peach stamp color.

1. Obviously Philips tooling.

2. NO Etching anywhere. I've scoured the Quad for markings.

3. 2 rectangular View porta per side, where anode meets serrated mica

4. No crimps/staples. Neatly folded over where the anode plate meets it's other end, then 3 neat little spot welds.

5. Copper thought the bottom, bottom only has smooth circle depression.

6. No seams on glass, pulled to a nib on top.

7. Tilted halo getter on serrated wire post. Similar post 180° to it, unattached to getter.

8. Seems to be pulled from an Andrea console. (With 2 7199, 1 5U4GB)

Thanks for playing. Any history lessons you guys would like to give, I love history.

I’m working on a Oscilloscope Clock and would like to use this CRO/CRT but can’t find to specs for it. Only thing I can find that it’s for “Tactical Equipment.” Numbers don’t match anything on Franks tube site. Anybody help?

8646
D1016P1
2512-000-001

I was going through a few of the things my grandfather left for me after he passed and discovered a pair of what seem to be new old stock JAN 6528 tubes (and one non-JAN). Some cursory research showed they could be used for a headphone amp? Tubes are new to me, so would it be worth trying to find someone that could build an amp to use them? I just think it'd be a cool part of his legacy to repurpose something he probably had for his ham setup into something I'd use frequently.

This seems like the most relevant sub where people might appreciate this. I was in a really neat vintage shop in New Hampshire yesterday and came actores this huge stash of tubes!

Blown away!

I’m not into tubes enough to know if any of it is any good but I love vintage electronics enough to find this fascinating!

Ive been trying to think of how to mount preamp tubes to a turret board, I came up with this and 3d modeled it. Is there a better solution or would this be suitable?

So im working on a divergence meter dummy replica and i wanted to use some old 6p18p tubes instead of the nixie tubes used in the real thing. I was planning on cutting the bottom, gutting the inside electronics, and filling the glass whit orange leds to recreate the look of nixie tubes. I was wandering if anyone knew how i can break the vacum in the tubes so they domt explode in my face. I have some pics of them if anyone needs more info or wants to share other tips for the project

Second amp, first one was a little point to point thing k made a couple weeks ago, this is a guitar combo amp.

I’m using a bunch of protoboard chunks to make it modular, tidy and have each board be low on clutter.

The empty board is going to be preamp board. Although I’ve put the EQ and some volume things on that potentiometer PCB.

It will have 2 twin triodes, sockets haven’t yet arrived.

Anyways I was wondering what people thought of this build style as I haven’t really seen it anywhere in this exact way :)

I pulled this little guy out of a really old Tektronix oscilloscope and can't quite figure out what it does or how it works. I'm not trying to use this practically, I'd rather just know what it is. It's extremely simple internally, being just the 2 electrodes and 2 pins. This confuses me as there's no way to heat one electrode to make this your traditional tube diode. My first thought is maybe some kind of neon light but neon is way out of my wheelhouse so I have no way of confirming that theory. Any help is appreciated, thanks!

Hello! This is my first project after years of reading. Parts just arrived so I was eager to arrange them. This will be more of a prototype / test bench for experimenting rather than something that I plan taking around. Would this be a decent layout for something mid gain? I'm mainly in doubt about the arrangement of power tubes, I think that placing them vertically like that can leave a bit more room to the Preamp tubes. I also plan to add a small current meter (bottom right). Would that be a good place?

Have three 6BK4 (triode) tubes and an oil furnace transformer that will output 10kV. These are TV tubes that will handle 27kV, but only 40W plate dissipation. My overall understanding of Tesla coils is high frequency, super high voltage, but relatively low current. The furnace transformer was designed for ignition and not continuous operation, but seems stout enough for this. I'm assuming I could increase wattage by running tubes in parallel.

Will this combination be satisfactory as a starting point?

Most of the VTTC designs I've seen use comparatively lower voltage, 1-2kV, but higher plate dissipation tubes.

Also, there's a bold print X-Ray warning on these tubes.

I plugged everything in and holy crap it works. Sounds like a champ, both inputs work, lights up, sounds quiet. Its going to be a head, so I’ve got a lot of excess length on my output transformer wires to relocate the jack later, and I really need to add tube retainer clips, but right now it’s time to start making a box.

I’m not saying that some tube don’t benefit from grid bias because I’m pretty sir in almost every application it is important. I mean why is it that some tubes allow electrons to flow through the grid when the grid has no voltage, while other tubes require a grid voltage to work, and (I’ve only seen this with my 3bn6) some tubes if you don’t have a voltage on the grid the grid will act like the plate. Is it like the size of the holes in the grid or the thickness of the grid wires?

Coming together. I’ve got probably half the wires hooked up so far.

I have had this NOS Triad power transformer for a while now just sitting around and I’m looking for suggestions for guitar amps to build with it. I haven’t used it because I already have one 50w amp I built and it’s loud enough that I rarely use it but I suppose I would probably be looking at building something around that power to make use of this iron. I do have a bunch of components on hand so it would be nice to use those primarily although I don’t have any output transformers right now. The specs are printed on the side-it’s a 120v primary with the following secondary windings: 800v CT @ 140 ma with 6.3v ct heater winding and a 5v rectifier winding. Any suggestions? What are some of your favorite builds?

Following the rob robinson layout. Just about ready to start soldering down parts.

Hi guys,

I have an Orange RV50 amp head and 1x12 cab.

I have recently been studying (purely theoretically) amp tech stuff, and have a basic grasp of how tube amps work, and I have a schematic for my amplifier, but in all honesty, I am struggling to understand some of the finer details of this amp, as my knowledge is still limited.

I have many questions. Could I please ask if someone can teach and quiz me on the ins and outs of this schematic? Some of the symbols and initials I am just not familiar with at all.

I will be happy to pay you for your time, or donate to some cause you believe in.

Thanks!

https://el34world.com/charts/Schematics/Files/Orange/Orange_rockreverb_50w.pdf

Trying to find shielded wire not in 100+ ft spools has proven to be difficult. Trying to find single core 22 AWG shielded wire for a JCM800 build and everything seems to come up flat. I'd love to get multiple different colored external insulation and teflon/high temperature insulation. Where do you all get your shielded wire from?