First of all, I want to thank Skunkie for all the hard work and videos.
Most parts are in and ready to build. I am also bringing forward the pt and opt from and old amp. I would like to delete the volume control as I use a preamp. Do I need to replace it with resistor of similar value?
I will post a list of stuff not used from the BOM Soon.
thanks,
Johnny
Hi Skunkie,
I know this 300B schematic was designed to use the 6SN7 GTA/B. A friend insisted I try the Mullard ECC33/CV2821 which is a 6SN7. He said its a great sounding tube. From looking at the schematic he said it should work. What are your thoughts on the ECC33? thanks,
Johnny
Finally I got a chance to get it working right. I will post some pics in the show and tell section.
I have some concerning voltage measurements I can not result. B+ = 450v
414v = 445v
222v = 440v
94v = 100v
99v =120v
2.5v = 8v
the LED never on. I have checked all the wiring and resistors to be ok.
Thanks I feel much better now
With no load, the voltage will be much higher than the rating.
I think my power transformer is high on something. I got 850v at the secondary. Please see picture of original specs. Is that too high?
Thank you for your patience.
If you leave off the volume pot, make sure you do leave in the "Grid leak" resistor, this is the 1M one from the grid to the ground. I might consider lowering that to something like 470K if there is no volume pot. FYI this resistor sets the input impedance of the amp so check what your intended pre-amp wants to see.