Tube Amp Breadboard.....

[Jack Hester]

I am hopefully in the finishing stages of my breadboard. I've read a number of accounts, of other builds. And, those really got me to thinking. Never enough, though, to motivate me to build one.

But, a fellow over on the Hoffman Amp site (Silvergun) posted two of his builds. I missed his first thread, from back in 2013, when he built the first one. I did catch his second build, and links back to the first. Those threads made something click. There are plenty other threads on the same, but his made me realize that I had a large portion of what I needed, in my shop.

I am a pack rat, always rescuing parts that should have a use, though I haven't figured out exactly what, for most of them. Anyway, I won't try to remember all the details, as I am working rather long hours this Spring, and have built mine whenever I had a respite from work.

Here are pictures of the almost finished project:

[IMG:800:600]http://i132.photobucket.com/albums/q32/Jack_Hester/Guitar%20Amplifiers/Amplifier%20Breadboard/Breadboard_7_zps714bc2a7.jpg[/img]

[IMG:800:653]http://i132.photobucket.com/albums/q32/Jack_Hester/Guitar%20Amplifiers/Amplifier%20Breadboard/Breadboard_6_zps2715a45b.jpg[/img]

And, the thread that I narrated most of what I did:

http://el34world.com/Forum/index.php?topic=16714.0

When he finished his second build (the link in my thread, to his), within days, he had assembled an amp design from another member (Tubenit) on it. More than enough inspiration to get me started on mine.

As I like building 'tools', I will do it again, a little cleaner and with maybe a few additional features. But for the most part, I'm pleased with the results of the first.

Jack

[Bob S]

That looks great Jack. Such a handy piece of gear.
I wants one. Maybe sometime this year...

[Jack Hester]

Now that it's built (for the most part), it wasn't that bad. I work at a rather large power plant (coal fired), and we are in a very major outage, where we rebuild/repair/replace everything that needs attention. Along with this, there are some serious scrap materials to be had, if one is willing to get in some dumpster diving time.

So, the panel that I used for this build is a cast-off that I rescued. And, have had it for a few years. During this outage (2014), I rescued three more panels, just like it, but much better condition. Plus a similar smaller one, that will make a nice smaller breadboard. It would require a bench power supply, but be more portable. The one I have shown is very heavy. Won't be moving that one very often.

I'm already rounding up the materials that I have on hand, for the next build.

Jack

[xtian]

WOW!! Can't wait to see it populated!

[Structo]

Nice job on that Jack.

Looks like a lot of fun.

[eniam rognab]

im building a way less cool breadboard project..... i am super jealous! that looks awesome!

mine is going to be regular breadboards for ICs and such but i am designing a +/- 12v (or more) discrete variable regulated supply at a couple amps, nothing crazy, but i bought a whole crapload of normal breadboards for nothing and im a gonna build some SS stuff, maybe include a +5 regulated logic supply for an arduino or something..... THEN build a tube testboard, you beat me

yours is way cool, inspirational, im saving photos

[armillary]

Your project is fantastic, and with so much thought put in to it. Lately I've been exploring side by side comparisons. Specifically, 6SJ7 to 6SC7 (no comparison) and now 6SC7 to 12AX7 (or siblings). And I've always wanted to read an honest assessment of whether the inexpensive Loctal equivalents of Octal tubes actually sounded equivalent, (i.e. does 7C5 sound as good as 6V6?) So I hope you'll find room for a plug-in board with a Loctal socket or two.

[Jack Hester]

I hope you'll find room for a plug-in board with a Loctal socket or two.

I've some of those tubes. Actually, quite a lot, and I've never sorted through them. I should look for some of those sockets. The boards are way easy to make.

Jack

[billc]

Now that it's built (for the most part), it wasn't that bad. I work at a rather large power plant (coal fired), and we are in a very major outage, where we rebuild/repair/replace everything that needs attention. Along with this, there are some serious scrap materials to be had, if one is willing to get in some dumpster diving time.

So, the panel that I used for this build is a cast-off that I rescued. And, have had it for a few years. During this outage (2014), I rescued three more panels, just like it, but much better condition. Plus a similar smaller one, that will make a nice smaller breadboard. It would require a bench power supply, but be more portable. The one I have shown is very heavy. Won't be moving that one very often.

I'm already rounding up the materials that I have on hand, for the next build.

Jack

Very sharp! and really cool that you are "repurposing" some cast off equipment, have done some of that myself and it is very satisfying to make something useful from stuff that was headed for the landfill.

[Jack Hester]

Very sharp! and really cool that you are "repurposing" some cast off equipment, have done some of that myself and it is very satisfying to make something useful from stuff that was headed for the landfill.

Yeah, the guys at work have known for a few decades that I'm a scrounger and a packrat. Here's a picture of the underside:

[IMG:764:800]http://i132.photobucket.com/albums/q32/Jack_Hester/Guitar%20Amplifiers/Amplifier%20Breadboard/Breadboard_02_zpsbcc194da.jpg[/img]

Note the white fuse blocks, just below the PT in the center. I have a large sack of those, as one project at the plant had whole walls stripped of the old generation I/O components and fuse blocks. I was able to salvage a zillion of these. They were dirty and smudged from handling. The first ones that I cleaned for this project cleaned up with a toothbrush and cold water. Nothing else, and they look like new. Bought them for scrap, cheap.

And, even though I have completely run out of storage space, I still rescue such items. Sometimes, it takes years to repurpose an item. Sure is handy when you have it on hand.

Something else. Note the thermistors, just to the left of the fuse blocks. Each filament transformer (3) and the output of the auto-transformer feeding the PT, have a thermistor in line, to give each a nice soft start.

Jack

[KellyBass]

Wow! That's very nice! I've wanted to build such a device as this for quite some time...and wondered how I would approach such a project. It's great to see such an inspiring example!

[Jack Hester]

Wow! That's very nice! I've wanted to build such a device as this for quite some time...and wondered how I would approach such a project. It's great to see such an inspiring example!

Inspiration at times comes from from the examples of others. Mine did. And, the fellow that inspired this one is apparently giving his a real workout. I hope to do the same.

Jack

[Jack Hester]

yours is way cool, inspirational, im saving photos

Here's a PDF with the individual boards. I've included a concept of their layout, before I built. It's obvious from the build that I changed my mind a few times.

On the next one (I've got another panel just like this one), I've got a few improvements. That one will be later this Summer. Still, I'm pleased with the way this one came out.

Jack

[Jack Hester]

I'm on 2nd shift (for some unknown length of time) working startup on our Unit 2, at the power plant. Not getting a lot done, but it works better than long hours on day shift, like most of the Spring has been.

I managed to get the PT output wires brought out to the barrier terminal strip on the side. Also, got the all the OT taps brought out to the topside barrier strip.

Only thing left is to bring the three filament transformers outputs to the barrier strip, along side the PT connections. Maybe that will happen tomorrow morning. Then, I'll begin to experiment with something simple. This is what I have in mind:

http://el34world.com/Forum/index.php?topic=16893.0

I'll post my progress, soon. Have a good one.

Jack

[printer2]

More of an amp specific build. Might throw in some 9-pin sockets after this build is done. More a What-If build that I can take out of the house to get others to try it. Won't win any beauty contests.

[IMG768]http://i406.photobucket.com/albums/pp14 ... 06677e.jpg[/img]

[IMG768]http://i406.photobucket.com/albums/pp14 ... 38f7e8.jpg[/img]