Hi All, I have a couple amps in the works and trying to save a bit of money and using parts on hand. I have an AZ1 rec tube and socket and want to use it but I see that it is 4v on the filly vs 5v on most everything else. So, I my transformer, how can I take the 5v lines and knock them down to 4v for the AZ1??? Cheers.
Easiest way is a dropping resistor in series with the filaments.
If you have a 5V supply and need 4V, you only need to drop 1V.
Divide 1 by the filament current of the AZ1 and that is the resistor value you need.
If you have a 5V supply and need 4V, you only need to drop 1V.
Divide 1 by the filament current of the AZ1 and that is the resistor value you need.
Up to this point, I have been a kit type builder. Can you explain a bit more. Not sure I am catching what you are saying. Thanks in advance.
Be careful that the AZ1 has enough current potential for an amp - it's not the most robust rectifier out there.
500v - 60mA
400v - 75mA
300v - 100mA
More of a preamplifier tube really.
andy
500v - 60mA
400v - 75mA
300v - 100mA
More of a preamplifier tube really.
andy
Please make sure the internal resistance (Rt) of you transformer is not too low for this tube (or add some resistance if not sure).
If the rectifier filament winding is CT and the DC filter is connected there, a 0.47 Ω in each heater wire will do. The AZ1 draws a heater current of 1 to 1.1 A .
Best regards!
Best regards!
But since 1A is less than the expected/usual load of a 5V heater winding, two .56R resistors might be needed. Experimental confirmation to set the size of those rectifiers based on delivered voltage of that particular 5V coil would be useful.
cheers,
Douglas
(Hey Dennis!)