Hey all,
Taking a break from building my last modules, I finally decided to look into making a better use of my old boss rc-30 looper.
I stopped using it as I couldn’t properly sync it with any of my synth gear. I did use the .wav trick where you upload files that have the exact tempo you need so the looper will be “synced” to some predefined tempo but it is far from being sustainable.
So I managed to found the schematic online and I got to a point where I can use a 5V trigger signal to sync the looper using the tap tempo function.
I think that could work fine as the function can be enable or disable (using the the On/Off switch of the rhythm section).
I used a 2n3904 to mimic the press button effect of the tap tempo.
If I dont screw up the soldering I’ll post again with a sync looper.
Good idea, i had the same for my Delay pedal, to used it on fx aux in my mixer table.
i used a vactrol to control the tap tempo, and very happy with it !
hope the same for you 
Nice !!
I wondered about vactrol actually when trying to find a way to trigger the tap tempo. I used the transistor because I remembered using it for the one shot/bounce module from lmnc.
I am also sacryfying the battery compartment.
So it is working but it is not as good as expected.
I used the volca sample sync out to set the tempo on the boss rc-30 and it works great. Works fins with the sync out of the keystep as well.
The problems start when you use the record/play , looper, function. The rc-30 automatically calculate your transient length and “re” set the tempo on the fly so your loops are aligned together. By doing so it stops using the tempo settings and basically kills my whole idea.
But, a funny feature (and my way around this) is the fact that you can change the tempo of prerecorded files.
So now, I am :
1- syncing the looper to my tempo
2- record my loop ( or at least a certain number of patterns) on track 2 with the playback volume at zero
3- record/save the loop (sync off)
4- switch to track 1, synced tempo using the track 2 as the loop length.
It is very similar to uploading wav file of a defined length but at least now I can do it for any tempo.
So a semi-victory.
(And if anyone wants to do this, I used a 47k between my sync input and the transistor 2n3904)
Hello!! I am searching for thetalis in the R88 value of the same RC30… its burn and i want to change this.
Hi,
Not sure if that’s helpful, but the manual says
This is the link where I found for the manual/service notes.
No idea if the link or pdf are virus free… the website name is confusing 
Dear Bpbby,
Thanks foe investigating and putting your work online 
I just needed to share then that I use my RC 30 with the .wav-Trick and have all memory filled up, so I can access 4 and 8 bar loops in 2bpm increments from 80-140bpm.
This gives enough freedom to choose tempo almost freely for me for street music. But ofc it is no viable for djing with small tempo adjustments upwards.
Cheers,
Ulrich
Welcome, great to have another looper on board.