First build. need a little help please.

[rockinmac]

building a 5f1 my first build ever. where does the 5 vac center tap red/yellow wire go from the power tranny. It's a mojo kit. Thanks!

[ATL Strat]

I don't know that tranny, but power transformer center taps usually go to ground at or near the power transformer.

[rockinmac]

the schematic showing it going into a 100ohm resistor on the same rail as the heaters

[ATL Strat]

I don't know that kit, but it sounds like they are elevating the center tap with the 100R resistor to eliminate hum (instead if going directly to ground with it).

[rockinmac]

so it's fine to solder it to the ground rail right?

[Phil_S]

I just pulled up the Mojo 5F1 assembly manual. The PT has the following wires:

2 black -- these are the primary connections to the 120VAC wall supply.

Red-Red/Yellow-Red -- these are the high voltage secondary; ground the Red/Yellow as it is the center tap. The red wires go to pins 4 and 6 on the 5Y3.

Two green: these are the 6.3V filament supply. Somewhere on the filament run, there is a pair of 100 ohm resistors, one for each wire, and the resistors are joined at the same ground point. Ordinarily, the ground is made separate from the circuit ground. The instructions say to place the 100 ohm resistors at the pilot light, a typical location.

Two yellow: these are the 5V supply for the rectifier. Assuming you have a 5Y3, the yellow wires go to pins 2 and 8.

Page 4 of the instructions say to follow the color coded wiring diagram. Have you got that?

If there is a center tap on the 6.3V supply (don't see this in the picture in the manual), that gets grounded to the chassis, same spot at the Red/Yellow CT.

I am doubtful there is a 5V center tap. Post photos if you think I'm not correct.

[Phil_S]

so it's fine to solder it to the ground rail right?

No, a center tap goes on a ground lug that is held directly to the chassis with a screw and bolt. See my other post on this.

[rockinmac]

I just pulled up the Mojo 5F1 assembly manual. The PT has the following wires:

2 black -- these are the primary connections to the 120VAC wall supply.

Red-Red/Yellow-Red -- these are the high voltage secondary; ground the Red/Yellow as it is the center tap. The red wires go to pins 4 and 6 on the 5Y3.

Two green: these are the 6.3V filament supply. Somewhere on the filament run, there is a pair of 100 ohm resistors, one for each wire, and the resistors are joined at the same ground point. Ordinarily, the ground is made separate from the circuit ground. The instructions say to place the 100 ohm resistors at the pilot light, a typical location.

Two yellow: these are the 5V supply for the rectifier. Assuming you have a 5Y3, the yellow wires go to pins 2 and 8.

Page 4 of the instructions say to follow the color coded wiring diagram. Have you got that?

If there is a center tap on the 6.3V supply (don't see this in the picture in the manual), that gets grounded to the chassis, same spot at the Red/Yellow CT.

I am doubtful there is a 5V center tap. Post photos if you think I'm not correct.

i'm going with what you say. i just looked at the schematic and i was wrong. THANKS!!!!!

[M Fowler]

If you need the wiring layout send an email to mojotone and they will send it to you.

Mark

[rockinmac]

Thanks to all i finished it. and it works and very quiet. The only thing is input 1 jack doesn't work but input 2 works i can sort that out sounds great so much harmonics..... i think i'm hooked moving on to a 5e3 after i get the jacks working right and find out where i went wrong. Thanks again!

[Phil_S]

Jack wiring can be confusing.

[rockinmac]

Any tips?

[Phil_S]

Any tips?

Yes, one on each jack! LOL, the 1/4" phone plug is said to have tip and sleeve. The tip is the active wire. The sleeve is grounded.

Which type of jack have you got? The Switchcraft type (upper) or Cliffs/Rean type (lower)?

When you say the jack doesn't work, can you say any more? When you plug in, no guitar signal gets through? If that's the case, you have either no connection to the tip, the tip is grounded, or there is no ground to the sleeve.

Study the pictures. Remove and rewire the jack.

[vibratoking]

A 5E3 is a move in the right direction.

[rockinmac]

Any tips?

Yes, one on each jack! LOL, the 1/4" phone plug is said to have tip and sleeve. The tip is the active wire. The sleeve is grounded.

Which type of jack have you got? The Switchcraft type (upper) or Cliffs/Rean type (lower)?

When you say the jack doesn't work, can you say any more? When you plug in, no guitar signal gets through? If that's the case, you have either no connection to the tip, the tip is grounded, or there is no ground to the sleeve.

Study the pictures. Remove and rewire the jack.

Alright. But it sounds so good i might not even mess with it. i don''t know if it's the low input but man does it sound great cranked. I