Re: Artificial centre tap for GG 3CX1200
|
Thank you, Reid.?
I was only thinking about the RF part.?
I ignored the DC plate current part of the equation.
Forum readers, please excuse my oversight.
?
Meanwhile, I have found in my spares a NOS in the box Stancor Filament transformer #P-6457, 117/107 Volt primary, 7.5 V CT
@ 21 Amps, Insulation test 2500 Volts.? It weighs almost 8 pounds.?
Make me an offer.
?
73,
Dave, w6de
?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]>
On Behalf Of Brandon DX via groups.io
Sent: 3 December, 2023 18:55
To: [email protected]
Subject: Re: [ham-amplifiers] Artificial centre tap for GG 3CX1200
?
Hi Dave, the need is for a dc return, nothing in the way of capacitors will work.
Using AC on the filament a center tap for the dc return will null hum voltage.
The concept was raised of using a small filament transformer with a center tap having around say a 3A secondary at a voltage the same or close to the tube's fil voltage.
What hasn't been noted yet is that the primary shouldn't be powered up on the added transformer. that would lead to high circulating current in it and overheating.
Reid
|
