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Just because I already have some 10+ audio- and electronics projects started (and unfinished) and yet another 5+ sewing projects, I couldn't resist getting a Clementine-board myself and add another project to the list...

As I have tested (started to test) a variety of different designs for chassis I wnt for a new aproach this time. Normally all my tube amps have been boxes (wood or metal or wood AND metal), but now I have started off with a ... metalbox that I folded myself in a new fashion. As the compartment below the transformers often is empty or filled with PSU caps, I simply deleted this space - the caps are all onboard. The transformers will sit on the back of the chassis on a recess (guess that's a correct name) and the board with its tubes on the front piece where the chassis is 2" in height. I haven't gotten any PCB-mounted sockets and I have an idea of using ordinary chassis-mounted sockets soldered to the PCB with short pieces of wire.
I have already a Darling of the matrixed kind, but wanted to try the "normal breed" with my highly efficient horn, so here we go .... but slowly.

Here you may see the ideas behind my chassis. I will make some wooden sides and cover the bottom with a steel or alu sheet or maybe even a piece of mesh metal.

I have an ugly mains transformer (the one in the pic above) from excellent Frag Jan Zuerst (www.fragjanzuerst.de) in Germany. The tranny is very good, but the black paint peels off easily making a bad appearance.
This fella is rated 2*230V 0,1A 6,3V 1,2A 6,3V 3A. Guess that will be enough.
As OP trannies I am using a pair of cheap British ones: VT1087.

The rest of components will hopefully be found in my stores, but I guess the caps in the PSU have to be ought from somewhere. Also I want to include a volume potentiometer, but I guess adding a 100K pot with the wiper connected to the grid of the 6SL7 through a 1K resistor will work fine.
There will due to the geometry be some issues with connectors but I have possibly an solution for that ...


Have to remember to bring the metalwork back to my job tomorrow with the drill for the sockets.

Hi Magnus,

soundbrigade wrote:The tranny is very good, but the black paint peels off easily making a bad appearance.

Meh, shot of epoxy paint should do

There will due to the geometry be some issues with connectors but I have possibly an solution for that ...

Mount it on a 5cm deep box and put the connectors on it?


Cheers!

SH*T!!
When checking with all teh trannies, the chassis is too small = everything fits perfect EXCEPT connectors!!!

Anyway, I have ordered all the components and will have them withing a few days.

(Photos later)

Got the chassis in order; made a new and very traditional one. Will have teak ends. Box in alu/zink will paint it yellow or green.
Some obstacles:
I haven't really cared for the choke. Gote one lying around but is it small enough to mount inside the chassis.
Tube sockets - can I use the "normal ones"? (Of course I can, but how to mount them nicely??)
The speaker terminals that rae really nice are of some uninsulated model, so I have to drill slightly bigger holes and arrange some insulation. Got a piece of neoprene rubber that could work.

Neoprene rubber might be a bit "wobbly" and unstable, and might not take kindly to being so near to a eat source.

I generally use a piece of blank fiberglass PC board for insulating mounting plates. If that's not readily available, then a piece of plastic, or even some thin (1/4 inch / 6.35 mm)plywood sould do the trick nicely

/ed B

I had the idea of drilling the holes approx 2 mm bigger, have the rubber (or fiberglass or plywood or MDF (have 3 mm at my job)) on the inside and fill the recess with some kind of "goo". I also have thin sheets of a kind of insulator to put on the outside.

Drilled almost all holes in the metal top today. Added a hole for a tube rectifier. Got a 5T4, 5W4, 5U4 (or did I write 5Y4??) and a 6X4. The three 5V-tubes will fit OK.

I will try out a Ken-Rad 5Z4 (metal).
Order an IEC power inlet yesterday as I ordered some stuff for indicators I promised my boss to do.

Stil no njuw picktures but at leest all wholes are drilld in the chassis.
I was about to start the hole procedure from ze very beginning but with a brass sheat insted, but as I had so good progress I decided to continue with the alu/zink-sheet.

I still haven't decided on the speaker conns. Will I use the uninsulated or use some other with heavy insulation.


There are three missing holes: two holes to hold a small metalangel for the power switch - a very special arrangement and a hole for the actuator to the power switch.

This is top of my box. The choke may be too small. I may get me a heavier one.



And this is below deck:

It will bepainted yellow.

Did you know that Mao Tse Tung's comrades celebrated his birthday by singing "For he's a yellow good fellow ..."

*facepalm*



Cheers!

And Al Capone's buddies celebrated him by singing "For he's a jolly good felon"

/ed B

Sssssslllllllllloooooooooooooowwwwwwwwwwwwwwwlllllllllllllyyyyyyyyyy ....

It took me several hours to solder the sockets in place. Used normal non-PCB sockets solder in place by thick multistrand CU-wire. Worked OK.
I had to keep things a bit tight as the sockets will be screwed in the chassis. Well, that's where I meet next problem ...