Tube Amp Archive

Resistors already on the way ....Tanks SOrr

added this link to a schem.


http://www.network54.com/Forum/278792/m ... ic+Example[/img]

Power tube went south so after replaceing the fuse and putting other tubes in.......one was redplating before I could get to bias......Resistor off of pin 4 on that tube looked burnt but checked out at rated value close to the other tube....didn't expect that at all as I was high fiving myself when ...

I have some Shielded on the way :wink: Do have - volts on pin 5 and will check the plate v's I am pulling the jumper and possibly going back to the 500R/ 1k's as well. Cranked the preamp and it started fizzing as well....but cut it back before the fuse went......... Tubes are a nice warm orange but ...

OD entrance mod.....you move the 220k resistor and replace with a .05uf cap but you remove the jumper underneath where you put the resistor.....I just unhooked one side and shrinked it in case I wanted to go back stock.

WForgot something.....when I did the OD entrance I unhooked one side of the jumper and left it hanging under the board........could this be giving me some of that classic parasitic oscillation?

Thanks Tom ......I checked on that but looks like they are out right now....
I'll do some snoopin!

I will dig into that one tomorrow Tom.
Snowblower is whooping me right now as I have about a foot and a half to contend with.

Merry Xmas

I also noted my tubes are cherry red even though they are biased around 34 ma.....somethings amiss.....my soldano's are nice blue with a tint of red.

I did try to isolate the blue wires as everything was all bunched together.....I will hunt down some shielded wire.....thanks

Thanks Gary ....I could't do much better on the pics unless there is someting in particular I should be aiming at......the sheilded wires all appear to be single end grounded....and I should be adding shielded to these other locations as well ? Is there a particular part # for the correct shielded w...

Am Pretty close to this .....need a 150 k for the FET resistor yet.

I'll try and do better with the pics.

A couple of leads in the OD area look pretty close together.

I will try the meter check for Osc.

Sorry about the terminology but actually the 360R was a resistor and I believe the voltage was the same on the screens and plates but will definitely look there !
Thanks for the hookup guys !

I was told this was Moss built when I bought it and the wiring looks real clean.......I copied a stock layout with voltages and added mine to it but mine is looking more like the tweaked layout right now.....so transpose my numbers to a 6L6 tweaked layout........... I will check the red plating out ...