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Wiring the turret board to the Pots:

I now soldered on the grounding lugs to the ground jumper that was soldered to the main ground line and also to the lead on the opposite end of the turret board that comes from under the corner turret.
I placed the turret board carefully into the chassis and bolted the ground leads from the input jacks and the ground from the turret board to the chassis making sure I had a good connection.

I then bolted the ground leads at the other (left end) of the turret board from the cap can, PT and turret board to the chassis.

I now located the turret board onto the mounting screws (remember that I had taped the screw heads to the top side of the chassis to hold them into place) and bolted it into place.

I now followed the layout and made all of the connections from the turret board to the pots.

Being as careful as I was I had still missed the ground jumper from the ground line to the normal channel volume pot, so I soldered this in now.

Double check all of your connections and mark them off on the layout as you go, inspect all of your solder joints with a magnifier.

Time: about 1 hour

Wiring the turret board to the Tube Sockets:

Now I wired up the turret board to tube socket connections.

Again I cut short sections of heat shrink tube and placed them onto the leads before I made the connections.

This was straight forward and time consuming as there are now a lot of wires connected to the tube sockets.

I now installed and wired up the boost and tube select switches, make sure that you use the lugs noted for making the connections.

NOTE: The switch operation is straight-forward, if you mentally continue the switch post straight back to the lugs you can determine which lugs are connected. Ex. If the switch lever is up, the middle and bottom lugs are in contact.

Time: about 2 hours

Start up and Voltage check, final assembly:

Before proceeding, check all of your solder connections and make sure that you have the correct wire to the correct location.

Read the Power Up section of the build manual a couple of times to thoroughly understand what you need to do.

Install the fuse into the fuse holder.

NOTE: At this time I have not installed or wired up the output jacks or the impedance selector switch as they block easy access to the tube sockets for checking voltages. I use alligator jumpers to connect the black and correct impedance lead from the OT to my test speaker so that the load is correct.

NOTE: Before proceeding, check that all of the pots are adjusted to the fully down position and attach the knobs onto them making sure that you line up the indicator mark with the “0â€

Just finished up my sIII V6 head this weekend. Here are voltages in the same format as those posted above by jcny, just for comparison. Mine were a bit lower overall than his. Any clue why, Stephen? Amp fired up on the first go-round. Sounds great through my tweed deluxe clone cab with a ceramic Tone Tubby. Planning on new cabs in the not too distant future. An amazing variety of tones in this amp, which is exactly what I was wanting. With the 6V6s the amp can sound quite a bit like my Deluxe, and with the EL84s and the boost - WHOA! - I've always been a Fender player, but I think I may be a convert. Thanks, Stephen, for a great kit! VERY IMPRESSED!

No tubes installed, power and standby switches ON

AC Mains: 121 VAC

Rectifier tube socket: from ground to either pin 1 or pin 7: 310 VAC,
across pin 1 and pin 7: 623 VAC

V1, V2, V3: across pin 4 and 9 of each tube socket: 6.92 VAC

V1, V2, V3: across pin 5 and 9 of each tube socket: 6.92 VAC

V4, V5: across pin 4 and pin 5 of each tube socket: 6.93 VAC

V6, V7: across pin 2 and pin7 of each tube socket: 6.93 VAC

Rectifier tube only:

Power on standby switches ON

B+ 401 VDC

All tubes installed:

Power and standby switches ON

“Boost “ switch should be OFF

V1: 12AX7
Pin 1: 150 VDC
Pin 6: 142 VDC

V2: 12AX7
Pin 1: 166 VDC
Pin 6: 249 VDC

V3: 12AX7
Pin 1: 200 VDC
Pin 2: 48 VDC
Pin 3: 69 VDC
Pin 6: 194 VDC
Pin 7: 47 VDC
Pin 8: 69 VDC

V4: EL84
Pin 3: 10.5 VDC
Pin 7: 328 VDC
Pin 9: 313 VDC

V5: EL84
Pin 3: 10.5 VDC
Pin 7: 325 VDC
Pin 9: 313 VDC

V6: 6v6
Pin 5: 20 mVDC
Pin 8: 20 VDC

V7: 6v6
Pin 5: 18 mVDC
Pin 8: 20 VDC

Good job oxfordmini. Dont you love it when it works first time. What is the B+ with the tubes in? 401? and it drops to 330 at the power tubes?

Does seems a bit much of a drop so check the power tube wiring / B+ side on the board & can cap. Probably correct but just to be sure.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

All tubes in, power on, standby on:

B+ measures 342 VDC at the standby switch, 317 at the board, and 316 at the tubes (Pin 9 on the 84s and pin 4 on the 6V6, correct?) Sound right? That's a little higher than it was the other day (313 at the tubes).

Your B+ is definitely Good! I think you're OK, if a little low.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps