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HELP with breadboard layout!!!

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ok i have ordered parts and will be breadboarding an amp... i have lots of iron and parts and need advice on where and how i should locate everything on a small breadboard (actually a wood piece 2' by 3' approx)

my amp is a 6SN7 to a 6BX7 to a IT phase splitter to PP 6B4G's

i have:

2 power transformers
2 chokes for PS
2 output transformers
2 IT transformers (phase splitters)
5 filament transformers
8 octal relay sockets for tubes

my PS is dual mono but is sharing 2 input tubes 6SN7 and 6BX7.

so how far can any of these transformers and chokes be away from each other??

which of these transformers/ chokes produces most interference?

and also should I use a bus bar for ground or star ground everything back to the PS?

2 ground lines total. one for each channel.

any help would be appreciated.

Thanks!!!
 
I am by no means very experienced but i have bult a couple of amps and this is what i try to do.

basically keep each channel as far away from each other as possible to minimise crosstalk, i was suprised to see how much field coupling capacitors can give off which can be picked up by the other channel.
The mains trannies rectifiers, and chokes all want to be kept togeather as far away as possible from the circuits.
Chokes will need to be turned 90 degrees from the mains transformers to reduce field induced in their windings.

Try to keep wiring from the power supply short throughout, once it is past the chokes it should be pretty steady DC and you can move the cap banks closer to the circuits than the rest of the PSU, but avoid crossing signal wires with power wires.

Try and run heater from their RMS AC voltage but rectify it to DC, e.g. 6.3VAC triode, rectify the 6.3V and drop the excess over resistors to 6.3VDC, smooth with plenty of capacitance, i have found this to be good.
Use star grounds for each channel if you run from seperate transformers, make sure everything has its own personal wire to the star ground point this will save you time resoldering later if you get a ground loop.

I dont know measurements for how far away things should be from trannies and chokes (it will depend a lot on size, type of trannie, and voltage) but as far as possible is good, you can also put up copper sheets inside your amp to sectionj parts off.
use shielded wire for inputs and outputs and everything wired off the main PCB like volume pots.

this is what i try to do but theres probably a lot more tweaks and tips from others!

Craig
 
star ground help

so should the star ground be back at the power supply caps?

or star ground all input and output tubes then run this back to PS caps?

is there any online help about grounding and the best ways to do this?

anyone else got any different ways of grounding?

Thanks!
 
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