Tag board finished 6G15 Stand Alone Build

[Willabe]

Well I re-did the board layout drawing, (many times, feels like 100 or so  ) but I feel good about it now.

I used 2 different size turrets and also 2 different size eyelets. It's a 1/16" glass board so I couldn't use Doug's turrets, would have been less $$. Large turrets were used only for the 14g tinned copper buss wire, (hole) inside diameter will take the 14g wire.  

Side view is to try and show how I did the filter caps. I ran all the ground wires for each tubes circuit to it's own single ground star point/turret and then ran a single wire (18g) to the ground buss. Only the output 12AX7/7025 tube shares a single 22uF filter cap (I couldn't figure out how to ground the 2 halves separately with the tone and mix pots grounds). Took a while to work out the layout to do this.    

I tried to keep all grid wires as short as I could and instead left the plates long to not have to use as much shielded wire. That's why I choose to mount a few of the coupling caps directly on the pot's. Wire wound R's and 6K6/6V6 kR lifted in the air to get more cooling. Tried to use as much of a 3D approach with the wiring as I could, with turrets, and wires on/under/over the board.  

Here's what I built.....             (still trying to learn how to shoot/post good pic's)

3'rd pic is 100 ISO, much better. Couldn't get it to work before at 100 ISO.    

I'll post more pic's as I build along with the most current layout drawing.

Please, any and all comments/suggestions are welcome.


        Thanks,      Brad        



It seems to be easer to view the photo's by clicking on the attachment lettering/ file number.       
                        

[tubeswell]

Interesting number of filter caps. Got a schematic?

[Willabe]

Hi Pete,

No I haven't made one yet, but I'll make one now and post it soon. I didn't change/add much to the circuit it self, just the PS mainly. It looks like a lot of e-caps but there only 22uF/450v each. Rated at, 105 deg. C, 115mA ripple, 25 @ 85 cents each from Mouser.

Doug's turrets are $0.15 so, with 2 turrets ($0.30) + 2 @ 22uF/450v ($1.70) you get 44uF/450v in a small size, high temp/high ripple for $2.00+tax, not bad.  

In one of Gerald Webers books he said he likes to go with 110uF for the plate supply (PP or SE) and 40uF for the screen to keep the low notes tight and in tune. KOC writes in his books about how the lower the uF value of the cap, there's less high/low end distortion artifacts from the cap itself. So that's what I went for. My thinking is I don't want/need any extra color from the unit except for the reverb itself and some warmth from the tubes. That way I should be able to use it with about any amp and let just the amp color the tone.

I also wanted to see if I liked working with the radials, so far I like them. It is easy to put them very close to were their being used in the circuit.


               Thanks,     Brad


              

[Willabe]

Here's the schematic. Please let me know if you see any thing that's wrong.


             Thanks,     Brad    


        

[tubeswell]

Nothing wrong that I can see. However, this type of unit only needs 3 x 40-50uF to work perfectly adequately. Having said that, your build should work fine AFAICT.

Seeing that you've got two stages of RC filtering between the rectifier and the choke supply, I'm curious about the voltage on the PT (HT) secondary?

[Willabe]

Thanks for looking it over Pete.

In the original post slucky brought up the point of having a voltage increase from using a SS FWFB instead of a HW. That's why I did that, to drop a little voltage. If it drops too much I can take out 1 or both of the 20R's. I think I have to drop about 25v or so and I don't think those 2- 20R's are gonna do it. I'll know soon.

Here's the 1'st post, check reply # 16 for my PT voltage test's.

http://www.el34world.com/Forum/index.php?topic=12338.0

I'm gonna try and get the iron and power switch, jacks, ect, wired in today.


          Thanks,      Brad