Circulator weirdness

[boctok]

I thought that my troubleshooting on this pedal was over, but... It works sometimes, for a while. Sometimes it doesn’t. When it is working, if I turn the depth and sweep up toward max, it “ticks/thumps” with the LFO, until it quits working. When it doesn’t work, I basically get the dry signal when in phase mode and nothing in vibrato mode. Unplugging and re-plugging sometimes gets it going again, but not always. I’ve gone over every component and verified the correct values. I don’t see any bad solder joints or shorts. Maybe a bad IC?

 

[djmiyta]

i built this and have very little effect only with pots dimed can I hear barely any effect. I bought a couple of lm13700 from different suppliers one being Tayda and I think also Mouser swapped the Tayda ones with the Mouser ones and got way better results. I'm having a real hard time sourcing these at good price and being legit ones might have to go surface mount next.

 

[boctok]

i built this and have very little effect only with pots dimed can I hear barely any effect. I bought a couple of lm13700 from different suppliers one being Tayda and I think also Mouser swapped the Tayda ones with the Mouser ones and got way better results. I'm having a real hard time sourcing these at good price and being legit ones might have to go surface mount next.

Better results with which ones? I bought ones from Mouser, because I remember seeing some posts around saying that there were lesser quality ones out there and I figured Mouser would have the better ones, but maybe not. I would have gotten them from Small Bear, but they didn't have them at the time. The ones I got from Mouser had an alpha numeric string above the LM13700N which was 01ZVT84E3. I have seen ones advertised from Ali Express and Amazon of all places that have the string 93XLD9KE3. I figured the Ali Express ones would have been the lesser quality of the two. Do you know what the string is on the Tayda ones?

 

[djmiyta]

better results with the mouser ones although they arent hitting the mark for me either I'm getting slightly more effect using the mouser ones
I'd have to dig em out to check for those numbers. I'm curious what does the string tell you ? the manufacture and date? I have no idea

 

[boctok]

I'm certain they convey some meaning to someone, but to me, it just tells me that they are different.

 

[boctok]

Also, not sure if you can see from the image, but the ones in my pedal are from Mouser and are supposed to be Texas Instruments, but that logo, kind of a curved "N" does not look like any TI logo I've ever seen.

 

[benny_profane]

The string of numbers is date/lot manufacturing codes. You can usually find their meaning by referencing manufacturer info. That ‘N’ logo is National Semiconductor (i.e., one of the manufacturers that Tayda sells).