I am amazed at using an audio file when IR or TTL level serial could have been used. The possibilities of bricking the cpu are far too high. The A-S701 has some sort of music inactivity detector to go into a sleep mode, so presumably involved
I mean at the end of the day the audio file is digital and no different to 0s and 1s you'd send over IR/TTL or whatever other bus but yes, it is a very odd update procedure.
It is an ancient procedure and I guess Yamaha would have mention if their Amplifier could be updated / flashed trough USB for example as so many of their devices could be updated, or even directly trough the network in the case of some pretty old receivers.
I wouldn't bother with the CPU/firmware in an home use analog amplifier in the first place.
I wouldn't bother with the CPU/firmware in an home use analog amplifier in the first place.
Yes it has and it can be activated or deactivated but that detects inactivity only after several hours, the worst that you could get is a power failure or power fuse getting out right in the middle of it so I usually recommend the good old friend UPS when someone desires the firmware update option.
I just solved the clicking relay intermittent problem with my Yamaha AS 301.
After many trial for several years I finally take apart the push button power switch at the left bottom panel .
- desoldering the switch from pcb
- open the plastic switch cover to access the copper contacts
- the switch contains two switchs in paralell config.
- clean with smooth sand paper and alcohol the static and the moving copper contacts
- reinstall the switch carefully
Sand paper does not clean, it removes the coating/contact material of the contacts so the problem will definitely return (possibly as a different issue). Best is to replace the switch for a better quality one. The original one is drama quality and pin compatible replacement switches exist. It is up to you to find the exact right one but I think this one is an equivalent. Check the datasheet and always choose the sealed version!
https://de.farnell.com/c-k-componen...MI0Mzo0YefiQMVIZeDBx0UkzeUEAQYBiABEgKTXvD_BwE
We might forget it but Alps is like Shimano: they make both super quality and low budget break down stuff. It may also be that Yamaha even used Alps knockoffs.
*It can help to add the smallest you can find so 2.5 mm pitched 10 nF cap over the contacts. Had this with other devices that randomly switched on and off and/or refused to either switch on or off.
https://de.farnell.com/c-k-componen...MI0Mzo0YefiQMVIZeDBx0UkzeUEAQYBiABEgKTXvD_BwE
We might forget it but Alps is like Shimano: they make both super quality and low budget break down stuff. It may also be that Yamaha even used Alps knockoffs.
*It can help to add the smallest you can find so 2.5 mm pitched 10 nF cap over the contacts. Had this with other devices that randomly switched on and off and/or refused to either switch on or off.
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Your right but what about 2000-3000 sound paper or some polishing compound ? Many times we are talking only oxidation. Also personally I had very good results with a 40% Isopropyl - 40% Nitro thinner - 20% Acetone concoction.
Not to open other topics, it's odd that I had many Yamaha A-s Amplifiers to repair but the only series that makes the relay click problem is the 301-501-701. The 801 does an exception to this problem but it could have many other problems as well, had one with a shorted to ground processor chip... not fan at all.
Also had some A-S700 amps that where only blocked in protection mode and much more well build on that matter than the 01 series. I don't know but could it be that the clicking was due to a bug in the firmware that eventually would make the clicking problem ?
Never opened this exact version as I just replace this type (it is used in many devices) but they may have gold plated contacts. Gold does not corrode and sanding makes no sense then. It may have corroding contacts and then sanding is a temporary measure. The replacement has silver contacts but exists in gold plated silver contact version. Sanding contacts is from granddads time and was mainly done with sturdy power relays, it does not make things any better for decades now with placed/coated contacts. If pitting occurs the wrong relay/switch is chosen. I have had Sony amplifiers with comparable problems that switched when a smart phone was near. Then the cap helped. The cap also helps when the contacts bounce but it may then be necessary to use a 100 nF.
Yes I know about the firmware but pempek had a malfunctioning switch. Lately I have issues with encoders having a too short service life, it seems all is made to break down.
Yamaha is not the Yamaha of long ago anymore. Pity.
Yes I know about the firmware but pempek had a malfunctioning switch. Lately I have issues with encoders having a too short service life, it seems all is made to break down.
Yamaha is not the Yamaha of long ago anymore. Pity.
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