pearl f-605 electro echo analog delay Update

[lowstar]

hi everybody,
i scored a pearl f-605 delay today (maybe it´s no score at all...) 
anyway, does anybody have some information about it ?
i could not find anything on the web nor in the archives
thx and cheers,
lowstar

i have problems with the input signal, not being able to get a clean signal, it distorted even on low input levels.
opening it up today, i saw that the first transistor at the input looks like it has been replaced, because
1. the solderjoints look different than the rest of the board
2. the legs are twisted to match the pinout, which seems odd if a board would be designed for that tranny
the tranny is a MPSA 92M820
it also looks newer than the rest of the trannys on the board
does anybody have that delay and could you check the real tranny for me ?
or some schemo ?

thx and cheers,
lowstar

[lowstar]

this is a bump cos of the update

[Steve Newton]

The Pearl schems I have (from http://experimentalistsanonymous.com/diy/) show that they used either 2SC2240(GR) or 2SC1815(Y) transistors as the first transistor at the input. Now all you have to do is find the equivalent...

[MartyMart]

http://www.banzaieffects.com/europe/parts/transist.htm
2SC1815 listed here under "other transistors"

www.smallbearelec.com has the 2SK30A which is similar
and used in many Boss/Ibanez pedals from the same era !
There are differences and check the pinout !!

I'd go with the original if possible, the replacement may just be
running a little "hot" for that delay pedal, causing the breakup.

Marty.

[lowstar]

you people are great.  thanks ! 

cheers,
lowstar

[MartyMart]

Correction, the 2SK30A's are used for switching NOT as an input buffer etc !!

******* SORRY MY MISTAKE *******

Marty.

[lowstar]

i found the transistor that is in there now is pnp (mpsa 92)
but the 2sc1815 and 2sc2240 are npn

cheers,
lowstar

[Steve Newton]

i found the transistor that is in there now is pnp (mpsa 92)
but the 2sc1815 and 2sc2240 are npn

Hopefully that's your problem right there. Swap it out for whatever npn you have lying around and see what happens.

[Dirk_Hendrik]

I own one of these dalays myself. Therefore I guess  I can tell you all this transistor stuff will not solve yoyr problem. I never got a good clean signal out either. Posted schematics above do not apply to this piece of early Japanese vintage. It's unclear to me what signal level's these guys expected but it definitely wasn't focussed on guitars.

[lowstar]

would you mind looking inside nonetheless ??
thnx,
lowstar

[Dirk_Hendrik]

2SA495, PNP indeed

[lowstar]

thank you, hendrik
cheers,
lowstar

[gener]

hi lowstar, any luck fixing up your pearl?

[Bernardduur]

Hi.

I have a AD-08; I know it is not the same, but if someones needs a comparison of this delay unit for some reasons I am willing to help!

[lowstar]

hi guys, cool that threads like this come to life all by themselves again...
so far, i´ve had no luck with the pedal. i got a replacement for the sa495, but it works even worse than the one i had in there.
from what i see, it is not used as an input transistor, but for voltage stabi/adjustment with a zener diode. i´ll change that zener diode, maybe it is shot. if not, i could either replace the whole arrangement with a voltage regulator, or
bad thing is, i think all the trimpots would have to be readjusted (there´s a whole bunch of them in there...)
anyway, that was my worst "score" ever, i paid 75€, and the worst is, 30 minutes before i made that deal i turned down an offer to buy a yamaha octaver (the one with the lm13600 in there) for 20€. duuh!

cheers and happy new year to you all,
lowstar

[gener]

i recently posted about my f-605 on this forum. mine is also not 100%. and the link for schematic doesn't seem to have the needed info.

don't give up, it's worth fixing! fully functional ones can sell for over 300 dollars on ebay. that last one i saw sold for around 275.

a person told me that there are 9 transistors/1 fet/6 diodes in the f-605 - is that right? i'll check mine again when i'm back at my rehearsal studio.

[Dirk_Hendrik]

There's more than that delay:
Pearl

[Bernardduur]

Ha, nog een Nederlander......

Your Pearl page (link is not working BTW) still misses a lot of the pearl pedals BTW

[Dirk_Hendrik]

Corrected that link. Forumdialects.

No, it doesn't miss pedals. I would if I intended to make a page with a complete overview of the various series of pedals manufactured by different companies. All on that page is my personal collection. Therefore if I don't own something you won't find it.

[gener]

that's a nice page you have there.

mine seems to work...the delay works, but is a little noisy. but the duplex and chorus settings are extremely noisy, giving these wierd sounds that sound like bad radio modulating interference (like when turning the radio dial an not getting any signal).

anyone have a schematic of this little baby?