I had this kit laying around for a while and since now I have some time to spare due to lockdowns, I'm willing to give it a try.
Here are the schematics:
The output transformer is unspecified.
Do you have any suggestions on what should be a good match for it?
Also, what do you think of the schematics, overall?
If it's any good, I'm willing to try some good quality parts on it.
Thanks for reading.
Here are the schematics:


The output transformer is unspecified.
Do you have any suggestions on what should be a good match for it?
Also, what do you think of the schematics, overall?
If it's any good, I'm willing to try some good quality parts on it.
Thanks for reading.
They use a 3.5k output tx. Try it in triode by removing the UL connection from the output tx and put a 100 ohm resister from pin 3 to pin 6.
Thanks.
So, using it in triode mode by connecting the 2nd grid to the plate via 100Ohm will suffice?
Or I should modify any other parts of the above schematic?
Regarding the 3.5kOhm tx, what do you think of the Hammond 1630SEA?
It has a 3500Ohm primary with max DC bias of 135ma and an inductance of 42 Henrys.
So, using it in triode mode by connecting the 2nd grid to the plate via 100Ohm will suffice?
Or I should modify any other parts of the above schematic?
Regarding the 3.5kOhm tx, what do you think of the Hammond 1630SEA?
It has a 3500Ohm primary with max DC bias of 135ma and an inductance of 42 Henrys.
No other mods need be done. That tx is fine, I use the Edcor 15 watt 3.5k to whatever you load impedance is.
Optimum load impedance depends on the operating conditions.
Whay supply voltage do you plan to have?
And there is nothing wrong with UL.
Whay supply voltage do you plan to have?
And there is nothing wrong with UL.
I plan to have a B+feeding for the Tx primary of around 450V.
UL is fine but I intend to go for a non-linear this time.
UL is fine but I intend to go for a non-linear this time.
evonimos,
If it is not Ultra Linear, and there is no negative feedback . . .
It must either be Pentode mode (Non-Linear).
Or it must be Triode Wired mode (Most Linear).
(I think you meant to say Non Ultra-Linear)
If it is not Ultra Linear, and there is no negative feedback . . .
It must either be Pentode mode (Non-Linear).
Or it must be Triode Wired mode (Most Linear).
(I think you meant to say Non Ultra-Linear)
Yes, exactly.evonimos,
If it is not Ultra Linear, and there is no negative feedback . . .
It must either be Pentode mode (Non-Linear).
Or it must be Triode Wired mode (Most Linear).
(I think you meant to say Non Ultra-Linear)
I meant to say Non Ultra-Linear.
Please before doing anything start some study:
GU50
By the way what speakers you will be using using with the GU50 SE amp?
Regards
Thank you very much.
Actually, I read that this tube does well at 380V 80mA.
Or maybe even 350V 100mA?
It seems the 450V I had in mind is probably not needed.
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