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Voltages on AEGIS I.F. tuning transformers, RF coil & Oscillator coil.
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Return to top of page · Post #: 1 · Written at 2:53:59 PM on 9 February 2025.
	Vintage User Location: Corlette, NSW Member since 29 December 2024 Member #: 2695 Postcount: 22
Hi all again. As I have no schematics for this radio and have exhausted myself in finding out, I was wondering if anyone out there can help me with the operating voltages on IF transformers and coils? Installed are AEGIS I.F. tuning transformers x 2, RF coil, Oscillator coil. These four units are looped with HT supply from a dropper resistor. I don't want blow these up. maybe 150 VDC. let me know what you think. Hammer_651 Aegis Radio Circuit Diagram

Return to top of page · Post #: 2 · Written at 4:38:23 PM on 9 February 2025.
	Ian Robertson Location: Belrose, NSW Member since 31 December 2015 Member #: 1844 Postcount: 2551
Don't worry about it. The coils and IF transformers won't be bothered or damaged by anything under a few hundred volts. They don't have an intrinsic "0perating voltage". Unless you short a plate to ground, that is! In that case, the dropper resistor will protect you.

Return to top of page · Post #: 3 · Written at 10:03:35 PM on 9 February 2025.
	Brad Administrator Location: Naremburn, NSW Member since 15 November 2005 Member #: 1 Postcount: 7483
Document uploaded. ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾ A valve a day keeps the transistor away...

Return to top of page · Post #: 4 · Written at 10:39:03 PM on 9 February 2025.
	Marcc Location: Wangaratta, VIC Member since 21 February 2009 Member #: 438 Postcount: 5498
One must remember that with Top trimmer IF's, the trimmer on the primary can be damaged by using a metal driver & shorting it to ground, as its alive. Pin 8 of what is possibly 6v6, has no cathode resistor.

Return to top of page · Post #: 5 · Written at 1:57:04 PM on 10 February 2025.
	Vintage User Location: Corlette, NSW Member since 29 December 2024 Member #: 2695 Postcount: 22
Marcc and Ian. Thanks for your input. So sorry, I have forgotten to mark the top tubes. Left is 5U4G, then 6V6, maybe a 6SA7-GT. What size resistor should I have for the cathode of the 6V6? I always use a plastic knitting needle for tuning. Do you have any idea where I can get the Voltage dropper resistor rewound or possibly a new one. I have come up with a solution to use wire wound resistors for an alternative. Thanks again. Regards. Hammer_651

Return to top of page · Post #: 6 · Written at 2:49:56 PM on 10 February 2025.
	Robbbert Location: Hill Top, NSW Member since 18 September 2015 Member #: 1801 Postcount: 2141
This looks like the same diagram as before, since none of my concerns have been addressed. You could try 220, 330 or 470 ohms for the 6V6 cathode resistor. The grid bias should be -12.5 volts.

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