I'm tempted. However the talk of IM distortion of AC scares me. But then again...it seems less of an issue with 2a3 or other low voltage filaments.I’d suggest try it with ac filaments first to see how much of an issue it is.
On the other hand in my case I was thinking to also use the filament transformers for the rectifiers...since my main transformer only has HT.
The filament transformers do 6,3VAC/7,6A.
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I'm tempted. However the talk of IM distortion of AC scares me. But then again...it seems less of an issue with 2a3 or other low voltage filaments.
On the other hand in my case I was thinking to also use the filament transformers for the rectifiers...since my main transformer only has HT.
The filament transformers do 6,3VAC/7,6A.
Is this a Triad flat pack transformer where you added some copper shielding tape? This model has 6.3 v 7.6 A:
Just wondering because I was just looking at this series:
Item # FP12-3800, PC Mount Flat Pack™ Power Transformers On Triad Magnetics
Yup...that's the one I have.Is this a Triad flat pack transformer where you added some copper shielding tape? This model has 6.3 v 7.6 A:
Just wondering because I was just looking at this series:
Item # FP12-3800, PC Mount Flat Pack[emoji769] Power Transformers On Triad Magnetics
Whilst I am no magnetician
If you read Hammonds lit, (same tranny design) it already has low emi
Low Voltage PCB Mount - Low Profile - 2 VA to 48 VA (229 Series) - Hammond Mfg.
Are you going to use a coleman filament regulator
Erica
If you read Hammonds lit, (same tranny design) it already has low emi
Low Voltage PCB Mount - Low Profile - 2 VA to 48 VA (229 Series) - Hammond Mfg.
Are you going to use a coleman filament regulator
Erica
What about that large positive voltage that will be on the 2A3's grid? Won't that just drive the tube into saturation?I am a little worried that the DHT 2A3 filament will be warm long before the EL84 indirectly heated cathode is warm.
Also, I expect the 5U4G filament to warm up long before the EL84 indirectly heated cathode is warm.
That means all 475V will appear on the 2A3 grid, and slowly fall to 157 as the EL84 warms up, and the EL84 starts to draw plate current.
Thee will be Lots of 2A3 current at power-up time.
I like the circuit, but just take care to get the EL84 cathode warm first.
You might select a pair of slow warming Damper Diodes instead of the 5U4G.
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