pianokeyjoe

If it is a no power situation , the power supply is at fault. Sadly, it is most likely the capacitors and, or the voltage regulators. But indeed when there is no visible or smell signs, it is the regulators, diodes or rectifier which can fail after so many years with no obvious signs or warnings. The crystal material inside those devices breaks down. Trust and know, that if the caps go, you will see it and smell it lol. There should be plenty of help here from other users that can supply you with a schematic and a better clue. It is early morning here for me so I am giving my best answer from past experience. on various hardware. I too own, a CT701.. "gulp", I have not tested it yet in years..gulp gulp.. Doh!

Tone mix mode takes the 8 voices and mixes them down to monophonic but with 4 oscillators mixed(most of the better sounding tones are layered with 2 tones or "lines".),thus a thicker sound. The CZ 101 "lines" setup is as follows: 2 DCOs, and 2 "lines" per DCO. So 2 tones can be layered and each tone has 2 "lines" or oscillators. The polyphony is 8 max but only in single DCO mode with only "line 1" single(not layered). Very boring sounding but usable with effects machine. 4 note poly is the normal expected limit with most presets being layered with either 2 lines or both DCOs with one line each or in the case of mix mode, all four parts/lines mixed in a limited set of combinations. Now the here is something you need to know that you may not have known.. The CZ101 is 4 midi channel multitimberal. BUT each midi channel is monophonic. and receive only a single line or single oscillator tone per midi channel. If you layer lines/DCOs and so on, you get less midi channels to work with and mix mode is a mystery to me as far as midi because I never got that far with my unit before I regrettably sold it. I DO have the CZ3000 and CZ5000 and can confirm you get 4 and 8 Note poly play with mix mode as those keyboards are 16 note poly max. They are also 8 part midi channel multitimberal.

2200 microfarad 16V electrolytic capacitor is what you need..

Hi, yes, the issue sounds like a simple loose trim pot. At worse you just need to find another to replace it with which will be quite cheap, and at best, a resolder of the one in there now. Hope it works! I love my MT52/CT320s!

uh man! I had the same issue with my MT500 and I fixed it and now since it has been years(2018), I forgot what I fixed on it lol! I do know it was some simple component and not a transistor or ic. I think it was a diode as that is easy to check while in the circuit and they tend to act like a fuse that can blow easily when you tamper with the wrong circuits trying to circuit bend lol.. Oh my circuitbending dayz :D. The other could very well BE a resistor but assuming you nor the previous owner did any circuit bending and the battery situation is good, then you need to check the ribbon cables that go between the mainboard(biggest board) and the POWER/audio amplifier board(the board with your DC power jack and audio jacks). It could be also that some one tried using a center positive 9vdc power supply instead of the correct but harder to find negative center 7.5vdc power supply and that caused a diode to pop between the amplifier IC and the tone gen ic.. COme to think of it I think thats IT! Check the amp section. I hear the buzzing of the casio itself, and it is different with every sound you select so yes, all is well with the logic side of things, you need to concentrate now of the audio amp ic and test the resistors and mainly the diodes around that as those diodes would be used to prevent audio feedback and voltage back feed between ic chips, etc. You almost there my friend!

This sounds like a popped resistor or the cpu for the main sounds went bad. However, check the melody volume slider. Seriously, check the volume slider. The accompaniment section has a different cpu for it as well as different volume controls for it separate from the melody(main voices)section. check for solder or wire joints and the simplest.. spray electronic contact cleaner that has teflon or some other lubricant in it! Has to be lubricated ELECTRONIC contact cleaner, not ELECTRIC/TV contact cleaner! vigorously slide that sucker left and right to see if you hear static and sound while holding down some melody keys, say in the upper octaves? Report back what you come up with.

YES!! Thankyou! Now there are the best fit weighted keys for a full time musician if I ever heard and saw :D.

Since we are talking best weighted keys fit for a full time musician, Can I ask what Casio digital piano uses REAL wood keys?

LOL LOL! You would think that would help? But you would be wrong.. sadly.. And leaving the darn batteries in the Casio. that is the even worse problem since batteries leaking into the electronics causes much more damage than wrong polarity which blows on or 2 components and you can usually fix that but eaten components and traces? Not so easy to fix..

@Etaoin Shrdlu ok, my original thought about that wrong polarity was the correct one at least for you. Ok, I have 2 specimens to work with so it will be interesting what I come up with for both.

When ever I can dig out my PT20s, I will try this fix. Oh OH!! I thinks we got it!! Thankyou @dannzomatic

Ah yes, THAT old monster rearing it's ugly head again.. The old "using the wrong polarity on a Casio" bit. Yeah it is good at least no full damage. Though my other one does seem to have the memory reset stuck issue that @CYBERYOGI =CO=Windler mentioned to me but both my specimens did have battery compartment corrosion soooo.. Lets see where all this goes! LOL!

Oh man! SAME issue as mine! Look at your battery compartment for corrosion. Seems to be a common issue with all battery operated Casios that when the batteries are left to rot in them, the alkali eats circuits and causes havoc. I still can not fix mine. So yes, if anyone knows what is up and can offer a solution, we are all ears! Sad.. such a nice little keyboard. I have 2 of them actually, and one of them turns on but makes no sound. The other, makes the SAME sounds as yours.

The FZ1 DOES have a built in rudimentary wave forms synthesizer built in ROM BUT, to access this, you have to be in create sample or create preset mode? and select sound source.. internal waveforms.. instead of mic or disk or line in. Emm.. I never owned the CASIO FZ1 but I have the YAMAHA A4000 and they share similar operation in this. There are videos on youtube that showcase the CASIO FZ1 built in synthesizer. Now.. You are correct. The FZ1 is by default, quiet as it will seek to want to load SAMPLES by default, as does the A4000 from Yamaha as well as the Roland W30/S50 which also has a rudimentary synth built in but to access those wave forms, you have to enter the menu system in the sample create or edit function of each of those samplers. So.. Not broken, you do need to either LOAD samples from disk or line/mic(live recording), or select a internal waveform. I am not sure, but I think.. think, it may be saw,triangle, and square waves?

Oh man... Ok, the battery leaking debacle.. That is a bane of my Casio collecting existence. I can fully assure you that there IS damage from the leakage in the MT400V. First thing you need to do is take the open unit to a very well lit room and get a magnifying glass or something like it so you can see up close, the circuits and components. You WILL see traces that are darker than the rest of them which would be green. Also you WILL find component leads, which include IC chips, that have corroding or crusting or rusting. And lastly, if you look closely, there will be some kind of brown sticky goo or residue on the boards. The biggest giveaway will be the crusty green corrosion on some of the component leads and circuits. A saving method you can use is to apply white distilled vinegar with a tooth brush to all the boards and then wash the boards after thorough brushing with the vinegar, with bottle water or better, distilled water and then spray electronics contact cleaner that is plastics safe, and let the boards dry real good. Basically, a board washing may save the MT. IF you see corrosion at ribbon cable points, then you may have a real issue that may not be helped with a wash. I hate batteries in musical instruments... I do not trust them anymore.. Wonder why? To @Jokeyman123 YES, the same guy lol. Love his table hooters page! He has a wealth of info on the internals of Casiotone that amazes me for sure!