Rocket / Build

[pfarrell]

On the heels of the non-traditional Express build... Rocket seems in order by comparison, plus I haven't built an amp with EL84s—want to see what that's about.

Thoughts on the closest "official" schematic for the Rocket? The attached schematic seems to work with the only layout I've found so far (helpful for us non EE noobs)—also attached...

Seems a little debate about first cap with GZ34. I happen to have an 80uf on hand vs 2x 40uf, though this does seem to complicate the cap stack arrangement in terms of actually securing the caps in the chassis. Were these normally hot glued to the chassis? (and each other). That seems a little sketchy to me.

Also, I have a Heyboer PT with 260 and 300 taps—seems slightly under and slightly over the mark?

I'm sure I'll have other questions. Was going to make a board that's 2.25" x 9", based on my maths...no idea what KF used. Open to all thoughts and mods etc.

[martin manning]

Silicone is best for gluing the cap stack. 260 VAC on the PT seems pretty close... is that the unloaded voltage? Did you measure that?
Assuming the pots are 1" in diameter and scaling the layout on-screen I make the board out to be 10.38" x 2.38".

[joeboo88]

Hi. I believe the stack of caps was siliconed, using a silicone that won't hurt the outside of the caps. I used hot glue once and either I didn't have the right glue or not, but I dint like it.
I built my Rocket with 2 cap cans - 40/40 and 40/20/20/20. its not traditional but for me who cares. I also built a KT66 Rocket Reverb, and used a little board like the Express's bias board for the caps.
My 4xel84 Rockets PT is a Pacific 250 and 280 HT taps. I ended up using the 250 side, so I think your PT would be fine.

Do a search in the trainwreck section for Rocket and study how guys built theirs, that's what I did. I picked what would make sense for me.
my build is here
https://ampgarage.com/forum/viewtopic.php?f=1&t=30697

the layout and schematic in the trainwreck files are correct

the Rocket is a great amp, good luck

sorry Martin, I guess we were typing at the same time..... Its good to rely on Martin, he has a big bucket of knowledge

[pfarrell]

Silicone is best for gluing the cap stack. 260 VAC on the PT seems pretty close... is that the unloaded voltage? Did you measure that?
Assuming the pots are 1" in diameter and scaling the layout on-screen I make the board out to be 10.38" x 2.38".

Martin! Yes, unloaded. It's supposedly an HTS-5199, 300mA, Amp Parts Direct selling it as a one stop shop for TW amps—IDK—lots of opinions about iron—I'm not qualified yet to opine on one brand/build method over another—not convinced I'd ever be able to tell the difference for certain. I used that PT in your Express (bought 2)—used the 300V taps for that build—but the PT also has 260V secondaries available. I haven't measured it. I'll go with your board dims. For OT, I have an Edcor trafo 35W 4K3/5K2 which I've seen either winding speced for the Rocket—so, not sure what's "correct" there. Edcor also had a 15H choke.

[pfarrell]

Here's a board layout for checking. Dims came out a little different from yours Martin—components seem happy though.

[freakshow__]

hey joboo

do you have pics or a layout for the kt66 rocket you built?

curious that’s all. sounds like a fun variant.

[pfarrell]

Do a search in the trainwreck section for Rocket and study how guys built theirs, that's what I did. I picked what would make sense for me.
my build is here
https://ampgarage.com/forum/viewtopic.php?f=1&t=30697

Awesome build!! I added it to my files/notes....

[joeboo88]

Thanks… here’s a link to where I got my info from

https://ampgarage.com/forum/viewtopic.php?f=1&t=11343

And

https://ampgarage.com/forum/viewtopic.php?t=7300

I haven’t posted my Kt66 build

97531F7E-9C41-4CD0-8C09-BE674775EFCE.jpeg

Here’s a pic, I haven’t built my cabinet yet and the faceplate is for an Express, but I got the inspiration from RJ guitars so I’m keeping it

Sorry didn’t mean to highjack the thread.
joe

[aceofbones]

I just started populating the preamp board of my traditional Rocket build last night. It is 9 1/2" long by 2 3/8" wide. I got the turret board from RJ. It is also the exact same dimensions as the one I used from him on my Express, which also matches the dimensions in the Express files here...

http://ampgarage.com/forum/files/Expres ... rawing.jpg

The turret layout is obviously different between the amps, but the board size seems to be correct. In my express everything just fit as it should, and with the lack of power supply board in the Rocket, there is a little extra wiggle room.

This is listed in the schematics and layouts section of the Trainwreck files as Express, but if you scroll to the bottom there is a page on the Rocket chassis. The drill locations match up with this board size as well.

http://ampgarage.com/forum/files/Trainwreck_Chassis.pdf

[pfarrell]

Coooool. So close, here's an updated Rocket drill guide should anyone want a leg up in the future. My mounting holes are a little different from the Chassis pdf... but people can work it out...

(And no thread high jacking apologies needed—the more the merrier—nice builds!!!)

[gktamps]

It's supposedly an HTS-5199, 300mA, Amp Parts Direct selling it as a one stop shop for TW amps—

If you are interested in digging into the Rocket transformer discussions, here's a place to start...
https://ampgarage.com/forum/viewtopic.php?t=5964

[pfarrell]

Thanks, I had read that thread earlier... I have the PT on hand—it's talked about there a bit compared to Heyboer 9144, dual windings with lower voltages—I'll use the 260V taps on the 5199 and see where it nets out. It seems there's some questions regarding the Rocket PT specs—but generally lower voltage than Express or Liverpool..? I saw voltages on the various Express schematics from 380VDC to 410VDC—which is where my Express build landed with the 300V taps. SS rectification of course.

Here's an amp board.

PF-TWRocket-01.jpg

[gktamps]

Correct - lower HT voltages for the Rocket. I used a 5199 for one of my many Rocket builds - sounds different but still good. In fact, I've used several different PTs and OTs for Rockets. Each has its own character, but I have also changed up the signal caps and other components, added various tone shaping settings, even built one with 5881 tubes and big iron. Since I have so many, I like them to have their own take on the sound.
Have fun!

[pfarrell]

Thanks for that info gktamps!

Some parts... missing a few values—they weren't in stock...

PF-TWRocket-02.jpg

[gktamps]

What are you missing?