6g2 Brownface Princeton build

[StrummersOfThunder]

Bit of time off work due to surgery so I planned a few projects ahead of time, first of which is some amp builds.
First one im attempting is the least complex of the line up and im building it on behalf of another forumite.

Totally open to critique and constructive criticism/advice


Chassis and face plates off ZH on fleabay. Good stuff and reasonably priced.

[StrummersOfThunder]

Decided to go the turret voard way rather than eyelets.
I have a sheet of undrilled board but I had this 3mm thick pre-perforated board to use.

Turret staking gear. I got something of Banzai but the tool didnt work well at all. The anvil is fine. I ended up 'machining' a new tool out of a large nail which worked very well. Drill press is a new acquistion

[StrummersOfThunder]

PT mounted and wired up to its respective taps. (note: the green wire between the switcc and the fuse is an offcut left over from the heater supply wires. Im going to replace it but I dont have extra black wire to hand right now)
Im using a Hammond 290CAX PT and a multi tap OT 1760E
Im using the lower voltage secondaries on the PT ( 275-0-275)

Just test fitting the board / stand offs etc. Ill take it out to populate and attach wires before re-installing

You can also see ive opted for individual filter caps rather than the cap can. I did this so I have the option to seperate the grounding

Im more or less follwing the fender schematic save for a few upgrades which i'll document as I go along.

I found a twisted pair of copper 16g wire made for a really nice and stout ground buss

[MikeC]

I've used quite a few Zachmdhunter (ZH?) chassis and they are good/accurate.

[StrummersOfThunder]

I've used quite a few Zachmdhunter (ZH?) chassis and they are good/accurate.

The only trouble I had was need ing to modify it a little to accept the 290cax and the power cord strain relief

[MikeC]

I've used quite a few Zachmdhunter (ZH?) chassis and they are good/accurate.

The only trouble I had was need ing to modify it a little to accept the 290cax and the power cord strain relief

Its not so easy working with steel.

[StrummersOfThunder]

A picture of the chassis and face plate. Very impressed with the quality.




Ill be sending the face plate to sandy at emblems this week for printing (he advised this over vinyl decals)
Great work from @starfire once again on the logo design. GC

[jeremyb]

Oh wow yeah thats nice work on the chassis and faceplate, is Sandy gonna silkscreen it on there?

[StrummersOfThunder]

Oh wow yeah thats nice work on the chassis and faceplate, is Sandy gonna silkscreen it on there?

I believe so

[StrummersOfThunder]

Would this be over kill ratings wise for an output impedance switch ?
https://surplustronics.co.nz/products/6 ... SVR4TXp3Xx


The other local option :

https://oamarucomputers.co.nz/product/s ... le-switch/


Or are the 250v 2A mini toggles from Jay car ok ?

[MikeC]

Would this be over kill ratings wise for an output impedance switch ?
https://surplustronics.co.nz/products/6 ... SVR4TXp3Xx


The other local option :

https://oamarucomputers.co.nz/product/s ... le-switch/


Or are the 250v 2A mini toggles from Jay car ok ?

How much current is flowing?

[StrummersOfThunder]

Would this be over kill ratings wise for an output impedance switch ?
https://surplustronics.co.nz/products/6 ... SVR4TXp3Xx


The other local option :

https://oamarucomputers.co.nz/product/s ... le-switch/


Or are the 250v 2A mini toggles from Jay car ok ?

How much current is flowing?

Is this correct:
15w OT -> V = √PR
For an 8 ohm speaker V =√15x8 = 11v Current would be -> I=V/R = 11/8 = 1.4. for a 4ohm speaker 2.75 for a 16ohm speaker 0.7A

I was going to do 8/16 impedence switching
So the mini toggle should be ok?

[Jay]

Would this be over kill ratings wise for an output impedance switch ?
https://surplustronics.co.nz/products/6 ... SVR4TXp3Xx


The other local option :

https://oamarucomputers.co.nz/product/s ... le-switch/


Or are the 250v 2A mini toggles from Jay car ok ?

It will work provided amp rating is sufficient and you only need to switch between two options. Also, it can get knocked out of position...

A better choice is this:

https://www.amplifiedparts.com/products ... position-0

[StrummersOfThunder]

Would this be over kill ratings wise for an output impedance switch ?
https://surplustronics.co.nz/products/6 ... SVR4TXp3Xx


The other local option :

https://oamarucomputers.co.nz/product/s ... le-switch/


Or are the 250v 2A mini toggles from Jay car ok ?

It will work provided amp rating is sufficient and you only need to switch between two options. Also, it can get knocked out of position...

A better choice is this:

https://www.amplifiedparts.com/products ... position-0

Im aware of the better options but im not placing another overseas order for one switch (for obvious reasons)
Im thinking about a raised collet to protect it from being knocked to the wrong position

[Jay]

Would this be over kill ratings wise for an output impedance switch ?
https://surplustronics.co.nz/products/6 ... SVR4TXp3Xx


The other local option :

https://oamarucomputers.co.nz/product/s ... le-switch/


Or are the 250v 2A mini toggles from Jay car ok ?

How much current is flowing?

Is this correct:
15w OT -> V = √PR
For an 8 ohm speaker V =√15x8 = 11v Current would be -> I=V/R = 11/8 = 1.4. for a 4ohm speaker 2.75 for a 16ohm speaker 0.7A

I was going to do 8/16 impedence switching
So the mini toggle should be ok?

For DC the formulea are correct. It will work for your scenario.