Hi Zoran,

> My Frequency Shifter has four TL064CN's and one TL084CN. That

single TL084

> is at the bottom, close to DOEPFER sign in the corner. Is this how

it is

> supposed to be

That is IC9: thus, that your IC5 is still a TL064, then it is likely
you have an earlier module without the modifications.

IC5 is the next TL064 up, near the PA382, or CEM3382 (and so not any
of the three-in-a-row at the top). On mine it has clearly been
replaced after the module was initially soldered. But an easier way
to tell if your module is modified is to look at the solder side,
where you should see 4 extra components: 3 of these are near the
underside if IC5 - (probably) an orangy-red zener diode (the key
component if it is missing!), a largish round capacitor (perhaps
marked '10u' or '33u'), and (probably) a flattish, square capacitor
(perhaps marked '1200' or '1000' or '1n' or similar); the other extra
component is a diode under IC10/78L09 (to the right of the right
MC1496, viewed on top).

If these are missing, the zener diode is the key one - whilst the
service manual says to use a 5V6, mine actually has a 5V1 one fitted.

(Locating the components on this board is tricky: the printing is
quite bad on mine, and of course most of the components obscure it
any way. This is one of the few modules for which I have the service
manual, which includes a picture of the component layout, so if you
need any more help, let me know.)

Tim