RH EF86/EL84 SE just for interest

[Tubeglow]

Another amp,

Its in constant use. I wanted an EF86 input with EL84 SE.
Its got an example of the relay select input.
(Tube rectifier) And I wanted all enclosed so I used a double skin duct system to keep the heat down.
Rh module is rubber mounted.
Front is olive wood, sides are red oak.
Finish is teak oil/shellac.

Just for interest I was going to build a mullard 3-3 however I wanted to hear this type of feedback and I get a few more watts

The transformer tube rectifier heater winding and circuits are protected with SS fusing.
Control voltage is from voltage doubler off the heater winding.

Its my most recent build.
I prefer the cruise light as an on indicator is not "In your face in the dark". Diffusing is with a hot glue lens on the base.

The duct is in the top of the amp and mounts onto the top of the tube rectifier divider (the top is a slide in fit from the back).

Just for interest.


Tubeglow.

[ValvoStef]

Nice one. I love the enclosure, looks very professional. I wish I was that gifted

[Tubeglow]

Just for interest,

The venting in the top.
And top build+ start of PSU.
All metalwork is Earth bonded.
This was just the start of the top build and side strength was increased with wooden strips plus the aluminium.

Tubeglow.

[ParcGwyn]

Very nice.

Dave
GW7ONS

[Tubeglow]

This was an interesting build.

I wanted something that was a bit safer in an area with a lot of use etc.

Components are:

Resistors RRR/Takman/Kiwame.
Capacitors Kimber Kap/Mundorf tube cap/Nikon KZ Muse.
Rectifier 5y3.

Output transformers. Edcore.

Cable PTFE.

A few pictures of the build for interest.

Tubeglow.

[Tubeglow]

Last few.

A modification that worked well was to lift the power transformer off the chassis with metal spacers giving more room to drill the base plate with more vent holes.
The input is switched via rotary switch wired with dropper resistors to keep the non selected LED's glowing to see the selection position in the dark.
The picture of the top shows the earth bonding and fixings of the mesh. (First part done in the photos).
At night you can just see the heater glow inside the unit.
The base plate is suspended from the side cross members with aluminium angle.

Tubes are Mazda EL84 and Mullard mesh EF86.

NB most of the work was done with a Dremel.
Its sometimes nice to see how projects are put together.

The EF86 bases are also mounted on rubber grommets to simulate the Mcmurdo anti vibration mounts.
The picture of the top just shows the metal pins that stick out into the front panel, using rear fastenings you would have to smash the enclosure to open it if you didn't undo the rear fixings.

Tubeglow.

[Tubeglow]

The selector input,

(Quick sketch)

Simple Rotary sw. The resistors can be reduced to give brighter back light so the position can be seen at night. In the day the none selected look off.

Tubeglow.