| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 2633.1 | | KOBAL::DICKSON | I watched it all on my radio | Mon May 06 1991 15:12 | 4 |
| The service manual's schematic should reveal if there is a trim-pot
somewhere inside. Otherwise you need a good magnifying glass and
a bright light to locate the pot by tracing the PC board from where
the cable attaches from the front-panel knob.
|
| 2633.2 | | WEFXEM::COTE | The keys to her Ferrari... | Mon May 06 1991 15:41 | 4 |
| Is the trimpot standard issue on these? I'd hate to go blind tracing
etches chasing some grail...
Edd
|
| 2633.3 | call for help! | KEYBDS::HASTINGS | | Mon May 06 1991 18:19 | 3 |
| try calling Ensoniq! Or even better, if you get the Transoniq Hacker
magazine, they publish help numbers. I've had very good experiences
calling them for my EPS. There should be one in there for the Mirage.
|
| 2633.4 | | KOBAL::DICKSON | I watched it all on my radio | Tue May 07 1991 10:30 | 7 |
| Trim pots are easy to find on a PC board (once you know what they look
like). The hard part is figuring out which one is the zero-set for
the pitch-bend wheel, which is why you look closely.
Or you may luck out if the PC board has labels silk-screened onto it
as an aid in finding the right adjustment. Have anyone ever open up
one of these things?
|
| 2633.5 | | DCSVAX::COTE | The keys to her Ferrari... | Tue May 07 1991 11:53 | 4 |
| I've opened up the Mirage a number of times, but never noticed any
trimmers. But then, I wasn't looking. I'll try that next...
Edd
|
| 2633.6 | H/W or S/W trim? | TROA01::HITCHMOUGH | | Wed May 08 1991 08:59 | 8 |
| Just as a thought, do you know for sure that its a hardware trim?
Some synths have a setup procedure that requires you to move controls
through their range and then centre them. It zeros out the control in
software rather than h/w.
Ken
|
| 2633.7 | Do nothing and fix it... | DCSVAX::COTE | The keys to her Ferrari... | Wed May 08 1991 09:06 | 18 |
| ...no, I'm not sure of anything at the moment.
I opened it up last night and traced the wires coming from the wheel
back to J(n) where the attach to the PCB. Lo and behold, right next to
the jack was a trim pot. I attached a DVM to the jack and isolated
which two wires were the PB. I then moved the DVM to the trimmer but
couldn't verify that it was in the same circuit.
Tracing the etches was impossible last night. Murphy's law mandated
they be on the bottom of the PCB. To view them I'd have to remove
all the keys and the keybed. Then remove the "motherboard". Not last
night, I don't think so...
Oddly enough, after I reasembled and put the Mirage back in the studio
the problem was gone. Maybe just reseatting the connector to J(n) did
the trick.
Edd
|
| 2633.8 | | TOOK::DROBINSON | | Wed May 08 1991 15:15 | 7 |
|
I'm not sure who's law it is, but I've fixed more than a few things by
taking them apart, poking around and putting them back together.
Don't be surprised, congratulate yourself for a job well done. ;-)
Dave
|