Lite 2b(ish) from scratch !
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Lite 2b(ish) from scratch !
Hi all:
I'm planning to build from scratch an 18W Lite 2b(ish), by solid state rectification (but adding a resistor of about 150/200 ohms, to achieve some SAG).
Here are my questions:
1.- Do I keep the power transformer requirements, or can the high voltage secondary voltage, 290 VAC, drop a bit? With diodes, I will save the voltage drop in the rectifier valve, but I have to add the voltage drop that will occur in the ‘SAG’ resistor.
2.- Has anyone tried to feed the filaments of the 2 EL84 and the 2 ECC83 in series? I mean: instead of using a 6.3 VAC secondary, use a 12.6 VAC secondary. Yes, I intend to reuse several disparate power transformers, which worked in other lives, for other purposes.
3.- The latest layout available (JMPGuitars) is based on a turret board. As I am starting from scratch, what physical dimensions should this plate have, how can I currently get the pre-drilled plate shown in the layout, any current and inexpensive suppliers of turrets and the tool to insert them into the plate?
Thanks in advance for any help,
I'm planning to build from scratch an 18W Lite 2b(ish), by solid state rectification (but adding a resistor of about 150/200 ohms, to achieve some SAG).
Here are my questions:
1.- Do I keep the power transformer requirements, or can the high voltage secondary voltage, 290 VAC, drop a bit? With diodes, I will save the voltage drop in the rectifier valve, but I have to add the voltage drop that will occur in the ‘SAG’ resistor.
2.- Has anyone tried to feed the filaments of the 2 EL84 and the 2 ECC83 in series? I mean: instead of using a 6.3 VAC secondary, use a 12.6 VAC secondary. Yes, I intend to reuse several disparate power transformers, which worked in other lives, for other purposes.
3.- The latest layout available (JMPGuitars) is based on a turret board. As I am starting from scratch, what physical dimensions should this plate have, how can I currently get the pre-drilled plate shown in the layout, any current and inexpensive suppliers of turrets and the tool to insert them into the plate?
Thanks in advance for any help,
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Re: Lite 2b(ish) from scratch !
1. With a SS rectifier you can have a slightly lower secondary, but I wouldn't go too low. You can experiment and see how it sounds.
2. As long as the filament transformer supplies sufficient current for the tubes, it should be fine in theory as long as you wire them correctly. Learn more here: https://www.valvewizard.co.uk/heater.html
3. If you print the doc full size (or at least the turret board area) I drew those to scale. Make sure the PDF is set to print actual size, and not shrink or fit to page. Normally I could make a turret board for you, but I'm not cheap, and shipping outside the US will probably cost just as much as the board itself. Maybe Bieworm or somebody in the EU could build one for you.
2. As long as the filament transformer supplies sufficient current for the tubes, it should be fine in theory as long as you wire them correctly. Learn more here: https://www.valvewizard.co.uk/heater.html
3. If you print the doc full size (or at least the turret board area) I drew those to scale. Make sure the PDF is set to print actual size, and not shrink or fit to page. Normally I could make a turret board for you, but I'm not cheap, and shipping outside the US will probably cost just as much as the board itself. Maybe Bieworm or somebody in the EU could build one for you.
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Re: Lite 2b(ish) from scratch !
I sure could do that. Where is the member located?JMPGuitars wrote: ↑Thu 04/25/24 3:07 pmMaybe Bieworm or somebody in the EU could build one for you.
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Re: Lite 2b(ish) from scratch !
That is great. Shipping costs would be very reasonable
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"THIS should be played at high volume..preferably in a residential area"