Re: ++Gear Down!++ Repair Thread

Someone should open a robots repair shop me thinks.

@automatique it sounds like a a solder point that has come loose open it up and have a look for any cracks or cut traces.

Re: ++Gear Down!++ Repair Thread

I just picked up a casiotone 403 for cheap.  here are the two problems it has:


-the c and f# keys are not triggering the synth,  i've pulled out, cleaned and plugged in the ribbon cable from the keys to the synth and still no luck (could it be something other than the cable/socket contact?)

-not able to select different voices when the mode-set rocker switch is down, and when i hit one of the buttons for the tone memory i hear a weird dischord sustaining sound, and still no change of voice

the four tone memory buttons presumably hold the voice info that can be brought up by rocking the mode switch to set and hitting one of the 27 upper keys to select a voice

i would assume that a robot out there has had similar issues with a few notes that are not triggering on every octave and a fix for that

but if anyone has any knowledge of this keyboard and service manual pdf or the like, any help is def welcome and appreciated

check out the mod for this thing this guy has done:

http://www.youtube.com/watch?v=SvLMoyrfR9A

yeah boyeee

Re: ++Gear Down!++ Repair Thread

leftcorporation wrote:

Someone should open a robots repair shop me thinks.

i'm turning into a robot repair shop... cool

these last months i've fixed synths and drums and fx for among others endfest, alden tyrell, mick wills, orgue and now i have a sick 101 from vince watson.

and then of course there are the modified monotrons.. i seem to spend more time soldering than making music some days..
but its a good feeling to fix a broken vintage machine!

Re: ++Gear Down!++ Repair Thread

rude66 wrote:
leftcorporation wrote:

Someone should open a robots repair shop me thinks.

i'm turning into a robot repair shop... cool

How are you with retrofitting midi kits? And how about leak-affected polysixes?

Re: ++Gear Down!++ Repair Thread

been there, done it.. tongue

the midi kit depends on which one..

the polysix depends on the damage.. just did mick wills' one, but it was just in time..

256 (edited by Orbweaver 2011-01-12 08:36:28)

Re: ++Gear Down!++ Repair Thread

disregard. found one.

Re: ++Gear Down!++ Repair Thread

teknob wrote:
rude66 wrote:
leftcorporation wrote:

Someone should open a robots repair shop me thinks.

i'm turning into a robot repair shop... cool

How are you with retrofitting midi kits? And how about leak-affected polysixes?

Midi kit should be no problem i fitted my own 3P upgrade kit, works fine. Not sure about the leaky polysix haven't looked at one before. I fixed non working knobs on the JP8000 currently trying to fix an harman-kardon amp.

Re: ++Gear Down!++ Repair Thread

http://www.oldcrows.net/~oldcrow/synth/ … epair.html

All the info you need..

+++ Dont be scared honey, thats just the resonance knob +++

Re: ++Gear Down!++ Repair Thread

leftcorporation wrote:

Midi kit should be no problem i fitted my own 3P upgrade kit, works fine.

you'd be surprised how bad some people are with a soldering iron. or even with removing a connector. or even finding the connector.. or even finding how to open the synth.
i always say in case of doubt, dont do it. especially with an old and valuable synth. test your waters first on something less valuable, like an old casio keyboard or something.. it takes practice to become fluent with the soldering iron and to recognize synth parts..

Re: ++Gear Down!++ Repair Thread

ave fellows,
got a no more functional ensoniq dp/4 here. i've tryed to change the battery, but he's still in sleepy mode...brought it to an tech, but he's not realy familiar with it, so he asked me if i can come up with a circuitboard-diagram.
i only got a dp/4+ manual from the netz arround, but without cb-diagram, and then again it's a + one.
anyone maybe could help me out with such?
i won't believe he's gone..gone forever....
dankyou in advance.

Re: ++Gear Down!++ Repair Thread

my juno's a bit sick at the moment.  my tech reckons i need a BR662 and/or IR3109.  Thought I'd ask to see if anyones got any parts available or breaking up an old roland?...

Re: ++Gear Down!++ Repair Thread

Roland VCS~350 Vocoder going into the shop for intermittent power problems and my SH-09 which is too quiet and has odd problems after its been on for about half an hour...

+++ Dont be scared honey, thats just the resonance knob +++

Re: ++Gear Down!++ Repair Thread

does the juno-6 use BA662 a or b  VCA?  don't have mine around to check and found some conflicting info.. If anyone knows or can check, that would be great

Re: ++Gear Down!++ Repair Thread

ekranoplan - it seems the juno-6 uses the ba662 vca. the a version is a higher spec'd with less noise, but i doubt you'd hear the difference.

i just went through something similar when Bangkok Impact dropped off his SH-09 for me to repair. the BA662 is often used by Roland to make filters like this http://www.curetronic.com/curetrbau/neubau/100m.htm or of course as a VCA.

the brutal truth is that you're not going to find one easily or cheaply. the is the cheapest i've ever seen so far:

http://www.donberg.ie/descript/b/ba_662.htm

However, if you're desperate and industrious, you can find a cheap BA6110 VCA and adapt it to the BA662 layout. a couple of the pins are different, but most importantly you need to create a "current mirror" using a few transistors to change the control current that drives the vca:

http://roland-jupiter.org/viewtopic.php … e9380e2f50

more info on substituting a BA6110:
http://www.buildyourownclone.com/board/ … mit=Search

http://sneak-thief.com - raw electrofunk

Re: ++Gear Down!++ Repair Thread

yeah, i'd heard of that 6110 replacement.  was unsure if it would sound ok on a juno when all the other voices are 662.
I was confused over the difference between BA662a and BA662b.
this says its BA662a
http://www.vintageplanet.nl/pages/roland.html

The official parts list says a or b
http://www.fantasyjackpalance.com/fjp/s … juno6.html

and I def read somewhere else that ju-6 used ba662b

Re: ++Gear Down!++ Repair Thread

listen, i had an sh-09 apart in front of me 2 weeks ago.

the filter used 4x ba662b's and the main vca was a ba662a. i put sockets on the vca and tried switching them around - like i said, there was no audible difference in the a and b.

now if you had all new caps and rebuilt the psu, you might here the difference.

http://sneak-thief.com - raw electrofunk

Re: ++Gear Down!++ Repair Thread

I have an old Soundcraft 500 mixer and about all the light bulbs from the VU meters are broken. The light bulbs are axial and the diameter of the bulb should be only 3mm. I have tried 4mm diameter bulbs (I think these are standard), but they are too big and won’t fit into VU meters. So the specs are 3mm diameter, the length of the bulb is 14mm, 12V, 17-18mm wire on both ends. Bulbs with wires coming from the bottom doesn’t work, because the lamp position would be really stupid after installing these.

The model of VU meters is  Componex 2LX. I think these are the same ones which are also used in old Trident mixers.

One solution is to go for led’s, but I would rather not do that as I would like to keep it as original as possible. I have tried to go through Ebay, local electronic shops and Googled hours and hours of these, but I really cannot locate any. Does anyone have an idea where to get spare ones?

Re: ++Gear Down!++ Repair Thread

Could you tell me what kind of material is the best for slider dust covers? I need to change original whos worn out. Here's a picture below:

http://akadavar.neostrada.pl/images/roland_pg_300.jpg

269

Re: ++Gear Down!++ Repair Thread

akadavar wrote:

Could you tell me what kind of material is the best for slider dust covers? I need to change original whos worn out. Here's a picture below:

http://akadavar.neostrada.pl/images/roland_pg_300.jpg

the material above is called cork which is also used to make slipmats.
the functionality of this type of dust blocker is totally ineffective imo.
the best dust cover is one which covers your synth completely be it plastic or cloth.

Re: ++Gear Down!++ Repair Thread

My Juno-6 is acting up now.  I've only had it a few months   sad 

One of the voices is pretty crackly, and the level for that voice is extremely low unless the filter is wide open.  If this was a 106 I'd just assume I need to replace an 80017a, but this is a Juno-6 so, uhhhmm, now what?

ekranoplan - do the symptoms I've described sound familiar to you?

Also, when I opened it up to have a look, I noticed that some of the IR3109's are socketed, while some are not.  Doesn't seem to follow any type of pattern either.  I assume this is a sign of previous surgery on the synth?

Re: ++Gear Down!++ Repair Thread

@unicity
Sounds similar to mine.  I had voice 4 drop out completely.  Can you get the filter to selfresonate on that voice?  I think all the ICs were direct onto the board on mine.  I found a tech in the end to sort it out. Its working now, jsut need to find time to get to Glasgow and pick it up

Re: ++Gear Down!++ Repair Thread

ekranoplan - I can't get the filter to self oscillate on the stinky voice, no.  I guess I'll be on an IR3109/BA662 quest shortly.  Also after opening  it up again I noticed that the two big black capacitors by the transformer have some weird dried up goop at their bases.  I'm sure that's a good thing.  Fucking shit.

Re: ++Gear Down!++ Repair Thread

unicity wrote:

ekranoplan - I can't get the filter to self oscillate on the stinky voice, no.  I guess I'll be on an IR3109/BA662 quest shortly.  Also after opening  it up again I noticed that the two big black capacitors by the transformer have some weird dried up goop at their bases.  I'm sure that's a good thing.  Fucking shit.

since you mentioned some are socketed, take a felt marker and number each chip then try swapping the various ba662's to see if the behaviour changes depending on where you put it.

also, check my post about using a cheap ba6110 as an ersatz ba662:

http://www.robotsforrobots.net/viewtopi … 44#p152644

http://sneak-thief.com - raw electrofunk

Re: ++Gear Down!++ Repair Thread

Thanks sneak.  It's actually some of the IR3109's that are socketed, but I could still do some swapping to see if that changes the filter behaviour.  Hopefully it's just the filter or the vca chip that has failed, and not both.  I'll have another look but I don't think any of the ba662's were on sockets.

Re: ++Gear Down!++ Repair Thread

I've got my JP8000 working again like it should, with all the keys/ buttons and sliders working. It took a few hours and it looks like a dog's breakfast inside but it works. Will post pics soon.