Hi BearBoy
Thank you for your reply.. I’m not particularly technical, either.. I can solder a little, but fiddly stuff is at, or beyond, my limits.. and as you say - the cost of paying someone else to repair it, would be more than they go for..
and brand new/nearly new machines can be had for reasonable money, I guess..
I’ll keep an eye on the thread, though, and hang on to the machine - just in case.. it’s as good as dead, already, and if I feel adventurous, I can have a go without doing any harm..
Thanks again!
Boss Drum Machine Woes
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Pepe
- Posts: 2120
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
Re: Boss Drum Machine Woes
That's what I thought as well. If my unit stops working after the repair attempt it's dissatisfying, but not the end of the world. I received it for free with the Kawai K4 synthesizer that I picked up last year.
-
Pepe
- Posts: 2120
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
Re: Boss Drum Machine Woes
Well, these were a few completely wasted hours. 
I tried to replace the original tiny SMD opamps M5218FP with SIL-8 type standard-sized Mitsubishi M5218AL. It did not work. In the end my unit refuses to give out any sound at all. Too bad.
Three possibilities:
#1: I broke something when I desoldered the tiny SMD ICs or while I tried to replace the ICs and now something doesn't work anymore or has no connection to the rest of the circuit and I don't want to spend more time with the fiddly SMD parts to find that fault. I definitely DID break some conductor paths when desoldering the IC105, but I soldered the wires directly to the correct components and I double-checked that all the connections were intact.
#2: I messed something up, because soldering SMD stuff is way too finicky for me. That's not unlikely.
#3: The replacement ICs aren't compatible.
Should the ICs be compatible, then someone with better SMD soldering skills could rescue the units (tip: use wires that are long enough to place the bigger IC somewhere in the chassis - the battery case might be in the way).
I uploaded the BOSS DR-550 Service Notes on my webspace if someone needs it.
I tried to replace the original tiny SMD opamps M5218FP with SIL-8 type standard-sized Mitsubishi M5218AL. It did not work. In the end my unit refuses to give out any sound at all. Too bad.
Three possibilities:
#1: I broke something when I desoldered the tiny SMD ICs or while I tried to replace the ICs and now something doesn't work anymore or has no connection to the rest of the circuit and I don't want to spend more time with the fiddly SMD parts to find that fault. I definitely DID break some conductor paths when desoldering the IC105, but I soldered the wires directly to the correct components and I double-checked that all the connections were intact.
#2: I messed something up, because soldering SMD stuff is way too finicky for me. That's not unlikely.
#3: The replacement ICs aren't compatible.
Should the ICs be compatible, then someone with better SMD soldering skills could rescue the units (tip: use wires that are long enough to place the bigger IC somewhere in the chassis - the battery case might be in the way).
I uploaded the BOSS DR-550 Service Notes on my webspace if someone needs it.