I have a BK7M in for repairs at Roland. The bill will be close to $500. Is it worth getting the repairs done and then selling it for the cost of repairs? I’m mainly interested in keeping it out of the landfill and getting it into the hands of somebody that can use it. It’s not for sale at the moment; I’m just looking for input to help me decide if I should pursue it or abandon the chase.
BK7M
- Thread starter Wheezer
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Thomas N
Well-known member
What happened to it? I have one right now that looks like it will go in for repairs. I opened a separate thread about this issue a couple days ago on this site. MIDI disconnect errors. Your timing is of interest to me.
The symptoms were that it would boot up after it hadn’t been used for a while, and it would run without any issues. But if I powered it off, it usually wouldn’t power backup again until it sat idle for a few hours. when it failed to power on, it would get part way through the boot process. It would bring up the splash screen that displays “BK7M”, then go blank and not display the susequent menu screen. Once the boot failed, the game was over until the next day.
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I think it's very easy to sell a working BK-7m for $500. I'm mainly playing guitar now, otherwise I'd buy another BK-7m at $500 for a spare.
SteveBox
Well-known member
As with any device filled with micro-electronics, I doubt Roland actually repairs it, in the way electronics from decades ago could be repaired by replacing some failed components. Take a look at the following video to see what is inside a BK7M (at 13:18 he finally gets to the computer circuitry). It is not practical for anyone to actually replace failed components on circuit boards filled with complex micro-electronics that were manufactured by automated assembly and wave soldering. They will do some simple troubleshooting to determine which board(s) are not working properly and replace the malfunctioning ones and dispose of them. The $500 fee they quote is their price to cover the cost of any board(s) they might need to replace. The faulty boards will probably end up in the landfill you wish to avoid. How long do they guarantee the repair?
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Airy
Active member
This is a good thought! As we are discussing in the other thread (https://www.accordionists.info/thre...midi-frame-error-and-midi-disconnected.11271/) some electronics parts are going to age -- even sitting on the shelf of the manufacturer -- and this device or replacements aren't freshly produced at all.
My thought doesn't apply to the OPs question, though, because he directly wants to sell after repair.
$500 for a BK-7m that was recently repaired by a Roland authorized repair center is a fair price. Roland gave me 100% coverage for 6 months on my FR-8X when I had my board replaced. Four years later it is still 100%.
Yes, there is little that can be easily debugged and repaired in many electronic devices today due to custom logic/control chips and nearly microscopic wave-soldered components although manufacturers may have diagnostic devices to pinpoint common failures.
However, that said I have fixed a number of devices over the years with some simple techniques. One is using the eyes and nose to pinpoint burned discrete components (for those devices that have discrete components!) A burned component is rare, though, and not likely for something that works some of the time and fails others. What I’ve found more likely with symptoms as described by the OP, works for a while then again after a rest, possibly to cool down, is a heat-related failure but not always in a component but in a solder joint on the circuit board. What is sometimes called a “cold” solder joint can fail due to changes in resistance during the use/rest cycles. A suspect connection will sometimes look odd under magnification with a good light, perhaps less shiny. It may heat and cool and change resistance during use, working sometimes and not others.
I’ve fixed many of these over the years in things ranging from complex audio devices to simple auto air conditioner control circuits. The last “tricky” fix was to one of my $1000 Kurzweil synthesizers, intermittent to the point of being unusable. A thermal camera, small heat gun and a can of freeze spray can be a big help. A careful examination showed a potential cold solder connection - the fix was trivial, just touched the connection briefly with a hot soldering tip to remelt the solder. The box worked flawlessly ever since.
Granted, this is unlikely in a wave soldered board with custom ICs and micro components. For those about I can do is measure and trace the power supply voltages, especially checking any connectors and any custom ICs in sockets (increasingly rare these days.) Sometimes faults can be found by tracing with an oscilloscope, especially if the mfgr has provided schematics. And an electronics geek friend can be a huge asset!
I would at least try the freeze spray - when it won’t start, try cooling various sections, one at a time, and see cooling some spot causes it to start.
Or just send it back and let them replace the boards!
JKJ
SteveBox
Well-known member
Yes, these are all simple techniques that sometimes work. These may not be something the typical accordionist without an electronics background would feel competent at trying.
It would be interesting to know what service centers actually do. Common sense tells me they fix a device the least expensive way. Is it less expensive to swap in a mass-produced spare board, or to pay an hourly rate to a skilled technician to try some of the troubleshooting techniques you mention? My impression is that each device has a flat service fee, which is probably the cost to replace the internal boards.
A friend of mine once worked as an engineer at a consumer electronics company. He did not work in the repair department, but his engineering team did a detailed inspection of some failed units that were sent in by consumers. They wanted to find out why the devices they designed were malfunctioning. He told me a high percentage of the returned units had no problem at all, they worked perfectly.
I cannot tell you what they would do on this BK, but when I brought in my 8X, they did ~4 hours of troubleshooting and replacement of a board that was known to be having issues.
Intermittent problems are the worst to debug. I’ve had the “no problem” experience in things friends brought to me to see If I could fix. I first suspect connectors and switches - the unavoidable jiggles and bumps of simply transporting the device for repair can jiggle a flaky connection into working, at least for a while.
To attempt a repair the first thing I usually do is disconnect and reseat all connectors. Humidity and temperature changes can cause connectors and other contacts to move slightly or otherwise cause resistance changes. Sometimes first just wiggling connectors and/or the wires or cables leading to them can while powered up (if appropriate) can recreate the problem or temporarily fix the problem which then usually leads to a permanent fix. [Just one story: in the ‘80s I walked into a lab where several techs had been tearing their hair out for hours over a very expensive graphical computing device, pouring over schematics and tracing circuits while slowly going insane. This was back when it was common to put IC chips in sockets, especially in custom-built things, and there were dozens in that thing. When the guys left for a break, based on experience I simply pressed on each socketed chip with my finger until I felt one “seat” with a soft click. When the techs returned I said try turning it on again and it worked. I finally told them the secret and how heating/cooling cycles can cause things to move.]
For contact connections of almost all kinds my ”secret” weapon is dielectric grease. A thin film on a connection doesn’t affect electrical conductivity but can help prevent resistance by keeping moisture and oxygen away from the metal, inhibiting even minor corrosion, especially useful for things that are even sometimes used outdoors or moved between environments with varying humidity and temperature. (not needed on gold-plated connections). I use the stuff on everything from delicate electronics to contacts inside switches to household light bulb bases to vehicle battery connectors. Can be found at any automobile parts store or electrical supply house.
(yikes, sorry about another wordy post. I get carried away)
JKJ
Alan Sharkis
Well-known member
No need to apologize. Your approach to troubleshooting is very sensible.
I’m thinking back to a TV program that ran many years ago. It was a training program for firefighters. The topic was forcible entry, and the first rule of forcible entry is:
“Try the door. It may not be locked.”
I can’t tell you how many times a problem was due to a cable, a connector, or some other mechanical issue.
I’m thinking back to a TV program that ran many years ago. It was a training program for firefighters. The topic was forcible entry, and the first rule of forcible entry is:
“Try the door. It may not be locked.”
I can’t tell you how many times a problem was due to a cable, a connector, or some other mechanical issue.
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Chris Laarman
Active member
Intended as some consolation for the OP and whoever:
I have (or had) an intermittent issue with an electric guitar (a MIDI-ready one with three outputs). I pinned down its location to an output where two internal cables meet. I paid much attention to the more complex flat-cable connector, and only later realized that I should have checked the simpler one.
"Smile, darn ya, smile...!"
