From Kenny Balys Sent Thu, Feb 22nd 2018, 12:13
From Kenny Balys Sent Thu, Feb 22nd 2018, 12:13
Not adding much, just an observation: Roland gear from 1981 to around 1985 has issues with board traces sizzling away. Its happened a few times where I thought I had a bad IC and it turned out to be a trace. Its super easy to wreck a pad too. +1 on 70's and 80's 4XXX CMOS going off too. That is universal across all old gear. On 22.02.18 11:36 , Mark C wrote: > Brilliant, thank you Florian that makes perfect sense, I don't think > the top had been opened before so am hoping it isn't a broken trace. > > I have replaced a 4011 before in the DR55 and made the initial > mistake of using an unbuffered with weird results so I do have some > CD4011BEs lying around. > > On Thu, Feb 22, 2018 at 11:07 AM, Florian Anwander > <xxxxxxxxx@xxxx-xxxxxx.xx <mailto:xxxxxxxxx@xxxx-xxxxxx.xx>> wrote: > > Am 22.02.2018 um 11:43 schrieb Mark C: > > Several buttons on my Boss DR-110(w/ dinsync installed a couple years > ago) appear to have stopped working recently, it's a real random > assortment though - shift, 7, stop, snare & clap. All the sounds work > fine when triggered from a pattern though. > > > I assume "3" won't work too. If you look at the schematics you can > see that those five buttons are on the same bus: > > possible causes: > > * broken pcb track of the connection between the corresponding bus > and pin 16 of IC1, > > * dead D2A > > * dead NAND gate(2) in IC3 > > > My first attempt would bei to replace IC3, because these old 4011 are > known to fail. You may use any buffered 4011 derivate (HD14011... > CD4011BE or BP). Don't use a ...4011UB... (UB stands for > unbuffered). > > > Florian > > > -- http://www.florian-anwander.de >