Fender 600 champion reissue complete rebuild

[Mikante]

This is stock, i have the components on the top so you can see.

image.jpg

You have to agree with me the out transformer is too damn close the power supply.

[martin manning]

The orientation of the PT with respect to the OT is also important. Is your PT an upright mount type? EDIT, ok, I see your photo now... I would rotate the PT and the OT 90 degrees. You can experiment a bit by powering the PT (nothing connected except the AC power going to the primary). Connect your multimeter to the OT secondary and read the induced voltage (mV). Find the orientation of the OT that minimizes the voltage and mount it that way.

[Mikante]

But the orientation in the my pic is wrong, it is the opposite, the output taps are towards the power tube in the stock orientation.

[martin manning]

The PT might be fine as you have it, but I recommend you try the experiment described above to find the best position for the OT with respect to the PT. Typically the axes of the coils should be 90 degrees from each other and in different planes.

[Mikante]

The orientation of the PT with respect to the OT is also important. Is your PT an upright mount type? EDIT, ok, I see your photo now... I would rotate the PT and the OT 90 degrees. You can experiment a bit by powering the PT (nothing connected except the AC power going to the primary). Connect your multimeter to the OT secondary and read the induced voltage (mV). Find the orientation of the OT that minimizes the voltage and mount it that way.

Sorry, to avoid mistakes. I connect the primary of the power transformer to the cable and power on without connecting the output in anyway, right? I just place the ot where is supposed to be and check the secondary? No cables connection between the two?

[martin manning]

Sorry, to avoid mistakes. I connect the primary of the power transformer to the cable and power on without connecting the output in anyway, right?

Correct.

I just place the ot where is supposed to be and check the secondary? No cables connection between the two?

Yes, the magnetic field radiated from the PT will couple with the OT and induce a voltage there. You can listen to that with headphones if you like, but I prefer using a multimeter.

[Mikante]

Sorry, to avoid mistakes. I connect the primary of the power transformer to the cable and power on without connecting the output in anyway, right?

Correct.

I just place the ot where is supposed to be and check the secondary? No cables connection between the two?

Yes, the magnetic field radiated from the PT will couple with the OT and induce a voltage there. You can listen to that with headphones if you like, but I prefer using a multimeter.

I ll stick to the multimeter too

[johnnyreece]

This may go without saying, but make sure to tape off/cap the secondaries on the PT when doing this test. Personally, I just put wire nuts on them all.

[Mikante]

This may go without saying, but make sure to tape off/cap the secondaries on the PT when doing this test. Personally, I just put wire nuts on them all.

Yes, thank you for the advice, i will do that.
I also have an homemade device to where i connect the power plug.
Thanks to “uncle doug”

[Mikante]

New lay out
I could actually buy a new chassis that would make things a lot easier, meanwhile i can try fitting everything in the stock one.

image.jpg

[martin manning]

I would put the choke to the left of the 6V6, above the PT. It's part of the power supply.

[Mikante]

Ok, i need to replace the power cord and the output jack.

[Mikante]

Hello,
Here i am.
I had so much work this summer i couldn’t even lay a finger on my guitar.
Now i am back to normal.
I finally got all the components and i can start building my ptp fender champion.
Its all set and the following questions are just for learning purpose.

CA869310-D7F9-4E42-B890-4DCAB241B9C2.jpeg

About the resistors i marked with a red circle, what are they for? I m asking because i have studied the 5e1 circuit and i see differences i still need to understand.
I marked with an X stuff i will remove.
I also see there is a second fuse on the original 600 but what really strikes me, apart from the fact that i don t know what s there for, it’s the amperage, 4a, am i reading it right?

By the way, i hope you all had a great summer.

[Stevem]

Suffice to say that all the resistors you have circled need to be there and for more then one reason.

While on the subject of resistors I would up rate R10 to a 5 watt resistor for the sake of idle stability when the amp gets hot.

The output tube cathode bypass cap C4 ( across R10) should not be a 450 volt filter either.

A 25 volt will work as intended ( better ) and last longer.

This cap should not be mounted right against R10.

It should be mounted 3/8” away from R10 so it does not get baked by the heat coming off of R10.

You don’t want heat that rises off R10 bake it.

Fuse F2 is there in the tube filament power supply section to protect that secondary winding of the power transformer from from large overloads like when a output tube shorts .

A short like this many times will take a good while to blow F1 and by that time has overheated that secondary filament winding and done damage to it.

Lastly, there is no such part as a UF1N6007 diode.
The diode part number you want is a UF4007.

PS.
It’s very bad to not play your instrument for months on end !
Surly you could have found 20 minutes once a week to keep your fingers in shape?

[Mikante]

Thank you very much for taking your time to help me out.
I love how this little amp sounds even without modifications, that is way i d like to understand better.
In order for me to understand i usually look back at a 5e1 schematic and compare it with the one i want to understand.
Those three resistors are the very first difference i have noticed.
About the second fuse, should i implement this in the circuit board because i don t want to have two accessible fuse holder in the front panel.
About r10, on the original 600 pcb board that it is going to be replaced, looking at this resistor, it is almost black on one side. I guess there is a lot of heat there. I checked and the value of this resistor is still right but i don t like the look of it to be honest.
For this matter I have also ordered some 3watt resistor to use in the power section even though the schematic shows 2watt components there.
The cathode cap for c4 was going to be a 25v anyway, this was discussed in some other thread and i did take note.
I will mount this cap as you said.
Everything you said was very informative and helped me clear some doubts that i still had.
I did have 10 minutes now and then to play my guitar to be honest but that is about it
Luckily I m also a singer so i can practise even when I am at work, no one will bother, I m the only one in my workshop