Dynamic overhype build debug

[svstee]

I hadn't built a TS with buffers (just the ROG Tube Reamer) before, so I gave this layout a go


Volume is about 1/10 of unity with L.E.D.'s and cuts out entirely when I switch to the Si diodes. Voltages are as follow;

9v 9.29

IC1 (JRC4558)
1 4.26
2 5.01
3 4.40
4 0.01
5 4.21
6 1.41
7 7.42
8 9.29

Q1
C 9.29
B 4.29
E 3.91

Q2
C 9.29
B 4.15
E 3.71

Any thoughts? This isn't that hard of a build, I've checked the board with my 7x loupe and there are no solder bridges or bad trace cuts, I've double checked all component positioning. What's up?

Thanks.

[John Lyons]

Pin 6 and 7 are a bit high. Should be around 4.5V like the others.
I'd check for something wrong in that area.
Check the diode switch again. You may have the lugs
mistaken. Make sure you have all the jumpers in...

[svstee]

I just triple checked pin 6 and 7, the diode switch, and the jumpers. Everything is in order.

What about the transistors? Are they in the normal voltage zone?

[John Lyons]

I'm pretty sure that layout is correct. But what I would do is trace the layout against the schematic
and see what you come up with. Even if it is correct it's good to learn to trace out a circuit
against the schematic. If you don't have it just email me...

Did you confirm that the resistors were correct values?

I think the transistors are correct voltages... wouldn't affect your problem anyway.

John

[svstee]

I just plugged it in and it is doing something different now. If I roll the Tone knob all the way to the left, it gets loud and harsh, like a heavy fuzz with gating. when I roll it all the way to the right it does the aforementioned 1/10 volume thing, and in the middle 8/10ths of its rotation it sounds like a TS808 with the tone rolled all the way to the bass side. Both diode positions work. I think when I first tested it out I left the tone on the far right the whole time...
I changed the IC to a 4558 from a different supplier, no luck, it sounded exactly the same. Could it be a bad pot?

[Brymus]

I have a hard time with vero layouts,
But it looks like pin 2 isnt connected to the diodes in the FBL the right way.
But dont take my word trace it out ,I am probably wrong

[svstee]

Pin 2 does connect right, it goes directly to the center lug of the switch and either to the LED's or Si diodes. More than one person has built this from this layout, so I don't think the layout is the problem. I've compared it to a TS schem, I can't see anything wrong either.

[BAARON]

Have you checked the 0.22µF cap and 220R resistor on the center lug of the tone pot, to see if they're okay and/or the right value?  Your description of the tone control's effect makes me suspect them.