Do you think it could be the noise floor of the scope becuase when i switch the probe and scope to 1x it drops to 10mv and if i switch back to 10x on the probe and scope it goes up to 20mv
the grid resistors are all soldered directly to the socket nice and close the wires are a bit of a mess...
I actually have some of them SO-239 around i could put it on there lol see if I can talk with the truckers lol but thats a bit higher 27mhz
I've been checking every thing and it is coming in on the input of the amp seems like its in all of my sources
I seem to be getting some high frequencies in my amp around 4mhz-25mhz around 20mv peak on the output I don't think I would call it an oscillation but my question is if i add capacitor to the input or maybe a higher resistor would it help to remove that or should i just not worry about that
thanks
I was thinking it was only 0.5 db down at 8k it really dropped hard at 15k I did add 1k grid stoppers to all the 6bq5s and I did add the efb circuit
I do have other caps I may play with but I'm pretty happy with it there
I didn't realize it did that but it does make sense now that you say that I understand why it's there
Now does it matter where I put it in the string can I add it to the end or should I have it hooked up before the first tube heater I don't really think it should matter but I've been wrong so...
I'm going to try with out it first I think I can always add it in later
I'm getting my first oscilloscope Monday with fft if all goes as expected I might check to see what it does with and with out it
Thanks again
I've got one more question why on the efb schematic do you hook the output of the lm337t to the 6.3v heaters I suspect is has to do with removing 60hz hum
I dont really have an issue with hum at all and my power transformer has a 6.3v center tap if I'm correct I would not need to hook the efb...
Ive got one more question on the 5k pot on the efb schematic how many watts does it need to be I was thinking about getting a 2 watt pot but if i could use a normal 1/2 watt pot i would already have it
that load line simulation tool looks really great and I'm going to play with it a lot I'm sure. I have LTspice I just have not got it figured out yet lol I'm good with a soldering iron and have basic electronic knowledge but have no idea how to make LTspice work.
It seems as if my best...
looks simple enough it also looks like if i was to use 4 5k pots instead of 2 2k pots i could bias every tube separably I just dont know if its going to be worth it.
I think i read some where that you have used the efb bias Gadget73 was it a big improvement or would you just continue to use a...