#124 Build Started

[Bob S]

Thanks for the words of wisdom guys. I re-wired the pots as per schematic. Markus, Structo & Deric are right.
I appreciate all of the help. Will post more this coming weekend.

[markusw]

It makes my head hurt thinking about it.

Sounds familiar
It helped me with my thinking to have a "real" pot in my hands.
In the end the pot rotation always remains the same, no matter if you turn your amp "feet" in the air

[Structo]

It was probably the "real pot" that did me in in the first place.....

Glad you got it sorted before you got too far along Bob.

[dcribbs1412]

Looks great Bob
1st D style build...bettin' its not your last
take your time and have fun

Darin

[Bob S]

Quick update pics.
Much respect to you guys. These are not easy to build.
I realy appreciate the help.
Still need a PI trimpot & to finish the FET board.
Main things I've learned are :--
Take your time - dont do anything if you only have 15 minutes to spare.
Work from the outside in - great advice !
DONT fit the boards until you have double checked everything you can do is done & correct.
Dont think you know what you are doing.
DO listen to advice.
For a first D type amp DONT do a 100W upside down. Walk first then run.
Do have fun.
Thanks again guys,
Bob

[M Fowler]

Nice job on that one Bob.

[dcribbs1412]

Really nice looking build you have there Bob
Nice pots...I like those relay boards also
no Dale resistors?


Darin

[Structo]

Nice!
I like how you have your bias test jacks all in a row.
That is about my only complaint against the CE chassis was where those jacks and bias pots are.

Too close to the hot power tubes.
What kind of pots are those Bob?

Allen Bradley?

[Bob S]

Thanks for the encouragement guys.
Darin - no Dale resistors yet...
Tom - the pots are mixnmatch AB, Ohmite & PEC.
Running out of wire too - hence the screwy color scheme - must order more.

[Bob S]

Quick progress update.
Not sure of the current rating of the 5H choke I used. Looks small with the Edcor trannies around it... We'll see how hot it gets.
Need to check all wiring (3 times at least) before firing up.
Bring up on a variac. Test voltages.
Set bias - realy dont want to red plate these winged C's.
Check for magic smoke.
Change out the pre amp plate resistors for low noise type.
Finish the FET board.
Thanks again for the help - no doubt I'll need more once I fire her up.
Bob

[ecisthebest]

you're going to use variac without the tubes installed right? check unloaded heater/HT voltage, it'd be a little bit higher than the desired voltage but thats ok. set bias before you put in tubes so you don't have to worry about red plating anything. right?

[Bob S]

EC -yes, test voltages without tubes.
Set bias.
Fit tubes & re-test voltages. Tweek dropper string if req'd.

[RJ Guitars]

Bob,

that is really amazing work, I am greatly impressed! I'm not sure how to say thanks for sorting out and documenting the reverse layout tubes up build on this, but I am greatly pleased and appreciative that you've done it. You have some store credit worked up in my books so let me know next time you need something I can furnish.

rj

[Structo]

Are those EL34's?

[Bob S]

Tom - pm'd.
RJ - It's me who owes you & all others here who provide the opportunity for the rest of us to build something we could only dream about otherwise.
Much appreciated - thank you.