Ross Phaser query

[Kalimna]

Hello again....

I have now rebuilt the board, new board/cuts/links. So far it only has resistors on it, and the vref is still measuring at around 2.55.
I de-soldered each resistor from the first build, checked its resistance on my meter, and soldered into new board. I also checked the pots and switch connections - ok. The only thing that didn't measure up quite right were the 10k resistors, they measured at about 9.7k.

I can't see what might be going wrong here - any thoughts before I populate with the remaining components?

Is it possible this circuit works with a different vref to normal?

The only thing is that I am using the modded circuit with the intensity pot and vib/phase switch. Any chance this has a bearing?

Cheers,
Adam

[Ciaran Haslett]

Flat out with Jazz festival over here so I'll be slow to respond for a bit

Remove the 10K in the red oval and measure again.  I think this shouldn't be here.

[Kalimna]

Hi Ciaran,
Removing the 10k as suggested gives a new vref of around 3.2v, which is simillar to when i tried that with the first board.
I also desoldered the switch and extra resistor plus intensity pot. No further difference to vref.

Enjoy the festival!

Adam

[Kalimna]

A little bump here.
Any further thoughts on the dodgy vref? Short of mailing out the vero to someone else to physically check, I have been over it many times and I can't find any discrepancy from the layout.
If not, then I may just repopulate with the tested components and perhaps some fresh IC's. Just in case.

I do have a few other things to keep me going though (Fairfield Barbershop with trimpots, Tremulus Lune, Sparkle Drive with diode switch and a Saffron Squeeze - thought Id try out an 'unverified' layout too....), all layouts from this site. Soldering is addictive, but if I could press a 'layout the holes and drill the enclosure in one go' button I'd sure do it. Im also going to try a Catalinbread Naga+CB30 in one box, but all I have are 1590BB's.....

Again, cheers for the excellent site and helpful advice,
Adam

[GrooveChampion]

Have you considered building small circuits containing the IC's and checking them out that way? Sorry if you checked them already. Personally at this point I'd just rebuild the circuit.

[Ciaran Haslett]

Apologies Adam.  Been really busy recently so not much time for the hobby.  If you're willing to wait a few more days...I will build it myself and take some notes.  I'm actually in the market for a phaser so it's no trouble on my part.

Again sorry for the recent radio silence

[Kalimna]

Hi Ciaran - apologies if my post sounded cheeky (and none needed from yourself at all), it wasn't meant to be! I understand that people who post on here have lives outside of helping strangers on a hobby forum :)
Having said that, if you have the time to build up the board I would be very grateful. Particularly regarding the voltages. If it makes any difference (and looking at the layouts, it shouldn't), I made the modded version with the extra pot and vibrato switch.

Take care,
Adam

[GrooveChampion]

Hey man did you get the chance to test the ICs?

[Kalimna]

Unfortunately not yet - this pedal is on the back burner whilst I build up some others (Sparkle Drive, Tremulus Lune, Saffron Squeeze, Fairfield Barbershop and another one I havent decided on yet).
Cheers,
Adam

[Kalimna]

Hi,
A little update on my phaser.
I finished up my third build of this pedal last night (after an hour of nailing down an error - a resistor with one leg a row too low), and I think it is working (huzzah!).

The rate control is still a little cramped at one end of rotation, but I will try a couple of things there. The vibrato switch does have an effect, but it is subtle. As are the regen and intensity controls.
However, it sounds better than my Mk 1 version by some way. I have tried a fresh set of ICs (including a 5532 for the op-amp) and it seems to work with either new or old. I haven't checked voltages, but I think I may do for good measure.

So thanks for all your assistance/suggestions. Now onto something tricky :)

Adam

P.s. Ciaran - if you do get around to building this I would be quite interested on your thoughts too.

[Ciaran Haslett]

Sorry man....life seems to be getting in the way of a good time lately!  Glad you got it going

The Vibe setting on this will be pretty subtle.  I wouldn't expect it to be a very useful mod anyway.  Can't comment on the other controls as I haven't built it but it might be fun to inject the regen into the first stage and see what happens.  I'll try that when I finally build the damn thing which will be soon.  Coming up on summer holidays so our students ill be off.

I'll keep ye posted lad.

[Kalimna]

Hah - no worries :) Once I work out how to understand schematics for modulation effects, I'll give your regen suggestion a try too.
As it happens, I do quite like the sound, and can get a really nice Van Halen effect with a little overdrive. One to build again I think.
Enjoy your summer hols,
Adam