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Discussion Starter · #4 ·
I have stared at that schematic for a long time and thought about building it. It is essentially a 5F2-A Princeton, but with a pair of power tubes in single-ended format, rather than just one as in the actual Princeton (and Champ), and a paralleled pair of 5Y3 rectifier tubes for the added current requirement. Is the real increment to wattage, by adding the second power tube, enough to yield an audible boost in output level? I'll let you tell us, Alan. ;) Looking forward to your report.
Certainly I will report; I expect a stouter foundation than a champ or princeton and perhaps a noticable increase in headroom and volume(20% possibly if that can actually be described accurately) .
Mostly this is for my mind absorbing hobby desire...and it will look neat to nerds
 

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Discussion Starter · #17 · (Edited)
I built one of these 12 years ago. I think your Power transformer is too small with only 2A of 6.3VAC filament power. Steve Ahola from Angela wrote all the instructions etc and he recommended a Fender Deluxe size transformer so I ordered a Weber with dual secondaries.
You may be right...i have a 269EX also and it has 2.5 amps

.3 amps x 1(12ax7) = .3
.45 amps x 2(6V6) = .9

2 amps should cover it ...will see how it goes....making do with what we have is part and parcel of hobbyists and army personnel in the trenches back in the day and maybe folks in fly in communities
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Discussion Starter · #21 · (Edited)
269EX or 269AX? AX in the earlier pictures. l'm not sure either will work, 290BX or BBX would be the Deluxe PT's. Deluxe's had hellish high voltages.
I have both and hope either will work ...the 6.3 filament total draw is 1.2 amps for the three tubes.
As far as voltages go on the B+: I like the audio of lower plate voltages on champs and it sure wont be wearing out any tubes馃槈
I have 310 at B+1

I appreciate all the helpful encouraging suggestions. Thank you all.
 

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Discussion Starter · #23 ·
These particular power trannies offer a wall source variable option...with black and white wires i get tweed(lower by 15%)secondary voltages which is what I am using now

...using the grey and white supply wires I will realize higher voltages on the secondary....i think a dpdt on off on switch will be useful in some circumstances
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Discussion Starter · #25 ·
I had about 80 pcs of unknown brand sayal supplied "1n4007" supposed part #

Not trusting them for the long haul I have ordered some heftier and higher rated diodes to replace them...they may be in a box that arrived yesterday...

Do any of you have a preferred diode(s) for this rectification purpose?; if so, please provide canadian supplier and part #....i got dizzy looking at the mouser website
 

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Discussion Starter · #30 ·
A Hammond 280CX is rated 450+ watts...is this the XFMR of choice?
400VAC secondary will produce 565VDC, no-load.
6A filament current.
Is this the XFMR that you plan to use for the Angela? View attachment 450921
i am going to use what I have onhand and was not planning on ordering another piece...if the results are lackluster I will make the change.
I see a 1.3 amp total 6.3 current draw...6 amps would be unnecessary ,I think....
 

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Discussion Starter · #31 · (Edited)
Using the 269EX I lifted the centre tap and built a bridge rectifier with the 1N5408G s that arrived yesterday and upped the filtering resevoir somewhat to acheive a smoother quieter supply which read 499v no load and 345v on the plates(pin 3) loaded.

I preferred working with the larger diodes(eyesight and steady hands both failing in old age); I have little experience with solid state rectifiers.
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