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N_Cook <diverse@tcp.co.uk>: Nov 12 08:02AM Loss of pianisimo ? (heavy key press only to activate) on 2 keys. That area schema/views not on elektrot. 2 contacts per key?, one worn or dirty per key?

"Gareth Magennis" <gareth.magennis@ntlworld.com>: Nov 12 08:30AM "N_Cook" wrote in message news:m3v46u$ced$1@dont-email.me...   Loss of pianisimo ? (heavy key press only to activate) on 2 keys. That area schema/views not on elektrot. 2 contacts per key?, one worn or dirty per key?         Nearly always due to dirty or worn key contact rubbers. These are usually in octave strips available from the manufacturer. Don't bother trying to repair these with paint etc. Really. (Sometimes its just due to dirt - tobacco, pet hairs etc which can be cleaned off)   Each key has 2 contacts, one hits the PCB before the other, the time difference calculating the speed of impact, and thus loudness of note.       Gareth.

N_Cook <diverse@tcp.co.uk>: Nov 12 08:35AM On 12/11/2014 08:30, Gareth Magennis wrote:   > Each key has 2 contacts, one hits the PCB before the other, the time > difference calculating the speed of impact, and thus loudness of note.   > Gareth.   Assuming if not just grime, I have a large collection of zapper contact sheets, to cut a couple of dimples from, and give them a go

"Gareth Magennis" <gareth.magennis@ntlworld.com>: Nov 12 09:04AM "N_Cook" wrote in message news:m3v64r$krd$1@dont-email.me...   On 12/11/2014 08:30, Gareth Magennis wrote:   > Each key has 2 contacts, one hits the PCB before the other, the time > difference calculating the speed of impact, and thus loudness of note.   > Gareth.   Assuming if not just grime, I have a large collection of zapper contact sheets, to cut a couple of dimples from, and give them a go         No, no, no, no, no, no, no, no, no, no, no. Really.     I knew that was going to happen.   Gareth.

"Arfa Daily" <arfa.daily@ntlworld.com>: Nov 12 10:05AM "Gareth Magennis" <gareth.magennis@ntlworld.com> wrote in message news:6oF8w.1176982$xb.877395@fx08.am4... > Really.   > I knew that was going to happen.   > Gareth.   Oh ye of little faith, Gareth. I'm sure he would be able to make them work again nearly like new by coating with foil from a cigarette packet, or if it's a *really* professional unit, Bacofoil ... :-)   Arfa

"Gareth Magennis" <sound.service@btconnect.com>: Nov 12 10:16AM "Arfa Daily" <arfa.daily@ntlworld.com> wrote in message news:8iG8w.871147$ck2.32999@fx17.am4... > again nearly like new by coating with foil from a cigarette packet, or if > it's a *really* professional unit, Bacofoil ... :-)   > Arfa     There are a few issues here:   1. This is a piano, and piano players hit keys HARD.   2. The structure of the key contact strips is such that the shape of the moulding is the "sprung piston" that ensures both contacts land straight and accurately onto the PCB so the velocity of the key can be accurately measured. You cannot cut these things without destroying that keys piston and the ones around it that rely on their neighbours to keep its structure shape intact.   3. Mending these things with paint etc might work for a day or so, then your customer will think you are a Klutz for mending it instead of replacing it and charging money for labour instead of a cheap new part.   4. You can buy them from the manufacturers for a few pounds.   5. Give number 4, why on earth would you consider 2 or 3 unless the part was no longer available?         Gareth.

"Arfa Daily" <arfa.daily@ntlworld.com>: Nov 12 10:49AM "Gareth Magennis" <sound.service@btconnect.com> wrote in message news:_6WdndM-OYPrrv7JnZ2dnUVZ7vCdnZ2d@bt.com...   > Gareth.   *We* know that, Gareth ...   Arfa

N_Cook <diverse@tcp.co.uk>: Nov 12 01:35PM On 12/11/2014 10:16, Gareth Magennis wrote:   > Gareth.   I doubt it, the owner did not know 2 keys were half-working, presumably he used it like a mouse-organ (ala Python), from my preliminary on receipt testing. It came in because of idiotic Jalco type 1/4 inch sockets with no mechanical fixings, I will not be replacing with Korg approved crap, standard conventional sockets will go in there mechanically fixed so they do not flop about.

N_Cook <diverse@tcp.co.uk>: Nov 12 03:01PM I liked the potential booby-trap of the interboard connector, don't remember seeing that type of breakable union before. I was surprised how clean the contacts and pcb pads were. I'll go with the single fine blonde hair looped under the octave silicone sheet, though not directly over the pads when I got to them , it was looped around the 2 affected key positions, melded to the outer flange of the silicone. The pads , moving and static and diodes,traces etc all test as expected, otherwise. alance of probabilies goes with hair. It would be quite an achievement to fudge up a conductive pad replacement. The stepped arrangement of paired pads would not be a problem but that very squashy , ie thinned silicone , of the pedastal of each pair would be next to impossible to work-around, I assume they can split at that place , with heavy use or over time.

"Gareth Magennis" <sound.service@btconnect.com>: Nov 12 03:36PM "N_Cook" <diverse@tcp.co.uk> wrote in message news:m3vsnk$m6l$1@dont-email.me... > ie thinned silicone , of the pedastal of each pair would be next to > impossible to work-around, I assume they can split at that place , with > heavy use or over time.     Hairs, usually animal, are a common cause of failure here.   I might have seen one or two splits in my long time repairing these, but usually the contact patches wear out long before they start disintegrating. It is quite easy to split a perfectly good one when removing it from the PCB though, if you grab the "pedestal" instead of the more robust edges.   Some (Roland) are quite tightly held in place with oversize conical silicon barbs pushed through holes in the PCB, most just have interference fit silicon cylinders that push into holes in the PCB, which usually have a small hole in so you can use the wire from a ceramic power resistor to push them fully home.     Gareth.

Phil Allison <pallison49@gmail.com>: Nov 11 03:10PM -0800 Arfa Daily wrote:     > Haven't come across the HK one so can't comment, but might well be. This one > actually says Fender on it, but they might be trading the design around > amongst themselves.   ** Or just copying each others efforts.   It also has three preset 'settings' for soft, normal and > hard bias, accessed via a foil switchpad, and a toggle switch for 'club' and > 'arena' modes. Personally, if they must have user bias settings, I would > prefer three preset pots inside, and a three way switch.     ** Having users actually tweak valve bias pots is a bad idea - but having an automatic system with user selectable criteria is fine.     > kind of complexity. On amps that have a bias balance preset, you have to set > it a long way off before you can hear much effect, and even then, it's > usually only a slight increase in background hum level ...   ** On many Fender models (egs 135W twin and Super Twin) you can set the bias balance by monitoring the residual 100Hz hum at the output. But if that means a setting way off centre the valves are bad.   Read the blurbs I posted, the auto bias system is there to allow the user to change valves from old to new or from one brand to another and know the bias will be correct. Going from NOS RCA 6L6GCs to Russian 6L6wxts or 5881s and Chinese made KT66s etc with no need to see a tech is a big selling feature.   That H&K model even allows the user to change from EL34s to 6L6s.   However, the system cannot cope with faulty valves and may even be damaged by them OR fail totally like you found. Also, it is sometimes possible to put an octal valve in the socket out of key or having broken the spigot install it any position you like. Results are often dramatic.   IME having guitar players fool around putting valves in their amps is full of traps & hazards - owners are bound to fall into one sooner or later.     .... Phil

"Arfa Daily" <arfa.daily@ntlworld.com>: Nov 12 01:54AM "Phil Allison" <pallison49@gmail.com> wrote in message news:fbbce639-fae8-4da1-8d6b-c7740e8cd837@googlegroups.com...   > IME having guitar players fool around putting valves in their amps is full > of traps & hazards - owners are bound to fall into one sooner or later.   > .... Phil   Fully agreed   Arfa

"Arfa Daily" <arfa.daily@ntlworld.com>: Nov 12 02:00PM Bit of a result. Finally got a reply from Fender's service department. The nice man asked how old it was. We told him about three years and he said they'd had a batch of ones from about that time that had caused issues, so he is sending us one, from stock.   Arfa

doeabrams21@gmail.com: Nov 11 01:30PM -0800 when turning the set on the power light momentarily come on then go back off

Adrian Caspersz <email@here.invalid>: Nov 12 12:58PM > when turning the set on the power light momentarily come on then go back off   what color is it?   -- Adrian C

John-Del <ohger1s@aol.com>: Nov 12 05:18AM -0800 On Wednesday, November 12, 2014 7:58:25 AM UTC-5, Adrian Caspersz wrote:   > what color is it?   > -- > Adrian C   Also, in what compass direction is the TV facing?

"Gareth Magennis" <gareth.magennis@ntlworld.com>: Nov 11 05:54PM "N_Cook" wrote in message news:m3sp9l$tgj$1@dont-email.me...   On 01/11/2014 15:21, Gareth Magennis wrote: > I rang Peavey to try and quickly establish if they knew of anything that > might be overloading the chip, or was it just the chip.   > Gareth.   This could be your over-temp drop-out failure mechanism. Sitting quiescent for 1/2 hour and an IR thermometer to the TOP body 38 deg C. But if you point it to the rear it picks up 78 deg C of the 330R dropper that is enclosed on all sides by the ps pcb , heatsink,chassis and main board. Perhaps over hours and lack of through draft that radiator heats up the heatsink and so TOP , enough to trigger temp protect. Hopefully the holes I ground through the ps pcb and the staircasing of the h/s vanes will preclude that.           My TOP chip was obviously overheating, you could tell immediately by putting a finger on it. It would shut down in 10 to 15 minutes.   The new chip went back in the same place on the same heatsink at the same angle. This one did not get finger hot.       Gareth.

"Gareth Magennis" <gareth.magennis@ntlworld.com>: Nov 11 09:28PM "Gareth Magennis" wrote in message news:C3s8w.871131$ck2.282052@fx17.am4...       "N_Cook" wrote in message news:m3sp9l$tgj$1@dont-email.me...   On 01/11/2014 15:21, Gareth Magennis wrote: > I rang Peavey to try and quickly establish if they knew of anything that > might be overloading the chip, or was it just the chip.   > Gareth.   This could be your over-temp drop-out failure mechanism. Sitting quiescent for 1/2 hour and an IR thermometer to the TOP body 38 deg C. But if you point it to the rear it picks up 78 deg C of the 330R dropper that is enclosed on all sides by the ps pcb , heatsink,chassis and main board. Perhaps over hours and lack of through draft that radiator heats up the heatsink and so TOP , enough to trigger temp protect. Hopefully the holes I ground through the ps pcb and the staircasing of the h/s vanes will preclude that.           My TOP chip was obviously overheating, you could tell immediately by putting a finger on it. It would shut down in 10 to 15 minutes.   The new chip went back in the same place on the same heatsink at the same angle. This one did not get finger hot.       Gareth.               Just to clarify, these symptoms were observed with the unit dismantled and the PSU in free air, so I could put my finger on the chip/heatsink.     Gareth.

Cydrome Leader <presence@MUNGEpanix.com>: Nov 11 05:36PM > used the machine in some time.) Turning it with the power on freed it.   > I was just wondering... Other than the obvious (gunky grease), is there > anything else that would cause a motor to jam?   worn bearings can cause the rotor on some motors to jam into place. I've had to add spacers to induction motors to get them to run again when the axial play becomes too great, and non-bearing surfaces start to rub.

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