Juno 60 battery signs of failure

[ian wheele]

Hi all
I am interested to know about the battery fail signs with a Juno 60. I know Roland recommend changing them every five years,and I know about all the mods to make battery replacement easier. However,what I don't know is what happens when these batteries START failing. Does the unit work correctly, protecting memory until the very last second, or is there a gradual breakdown over say, weeks, with some patches saved and working correctly and some turned to garble. I assume the first thing to go is the facility to write NEW patches .
I have tested my (standard yellow) battery with a multi meter and it's a healthy 3.2v , although there are small discolourations at the top where the tabs are soldered. Unsure of the age of this battery, so I'm trying to find out all I can while I still have time. The clock might be ticking !
Also, when the 2032 battery modification is in place, can a new 2032 be fitted while the unit is still powered up, avoiding the need to reload all the patches again ? The mods I have seen have the 2032 holder mounted to the base of the main body, well away from the pcb or components.
Thanks in advance,
Regards...Ian.

[jxalex]

Dont panic or worry. If battery gets emty then nothing else happens than patches are forgotten when powering off the synth if the battery is empty. Thats the ONLY thing what happens.

The synth still works perfectly without the battery, only that there is no patch memory after synth is turned off. Try.

All the voltage over 2.9V is ok and avoid finger fat on the battery edges as it is somewhat conductive or etching too and making discharge.

[ian wheele]

HI jxalex thanks for the reply. Battery seems ok at the minute , just wondered what the symptoms of a gradually failing battery were. Also do you know if memory is lost when replacing 2032 batteries after modification when the machine is still powered up ?
Regards. .Ian.

[cornutt]

HI jxalex thanks for the reply. Battery seems ok at the minute , just wondered what the symptoms of a gradually failing battery were.

From what I understand, and if it's like the 106, you won't notice anything until one day your patch memory is scrambled.

Also do you know if memory is lost when replacing 2032 batteries after modification when the machine is still powered up ?
Regards. .Ian.

It would be a good idea to save your patch memory first. You can use the cassette interface to save all of the directly accessible patch locations. (I don't know if the cassette interface on the 60 saves the "hidden" patch locations or not.)

[jxalex]

HI jxalex thanks for the reply. Battery seems ok at the minute , just wondered what the symptoms of a gradually failing battery were. Also do you know if memory is lost when replacing 2032 batteries after modification when the machine is still powered up ?
Regards. .Ian.

I hope You are not performing it during live show.

There is no "gradual failing". Just there will be low voltage and garbled patches from one moment.

Replacing battery while unit is powered on? I do not know. What about trying?
I think the memory will be intact, also the battery voltage is feeded through the diode to the CMOS RAM circuit.

but it is dangerous to do such things on powered on unit --- so care must be taken that some metal elements
do not fall inside accidentaly (screws, screwdriver!). These may cause shortcircuit and damage other components.
However it is fine if You have such modification that there is a separate hatch for a battery

However it is always good to have a nice backup of all presets, whatever in sysex or a nice cassette or digital audio recording.

Further on, it can go 5 years before You even need to check the battery, but You may do this way if You really are into changing battery "live".
You may as well add another CR2032 battery (in parallel, with its case and feeding the voltage through the diode to the same point as the another battery is feeded to the RAM circuit in original schematic!). So before taking out old battery insert to the another battery holder already the new battery. it is somewhat geeky overkill but why not.

In some units are this kind of circuits used, but I have not seen this kind of trick used in synthesizers (I wonder why?), but which You may use too -- the self discharge compensation circuit.
You take from +5V rail through diode and 3k..10k resistor the voltage to the battery back (so it feeds the battery when unit is powered on). So this way it will compensate and charge with some 10..50uA current while the unit is powered on and also increases the battery lifetime.

[ian wheele]

Hi all. Thanks jxAlex, thanks for the info about dying batteries, exactly what I needed to know. If I were to carry out the 2032 mod I planned to house the battery in a small wired plastic holder well away from any components or boards, so should be safe enough. I also have a factory patch cd to reload sounds with.

Also, do you know what the pitch bend range should be ? I read in the service manual somewhere, that it is only +/- 7 semitones
But this doesn't seem much of a range to me ! Would have thought an octave up and down at least . Have inspected and cleaned the pot with very fine emery paper and electrical spray but no difference.

Regards. Ian.

[jxalex]

When You do the battery holder change you still need to make backup.

Pitch bender:
I dont know exactly the range.
Neither about Juno-60 or 106 (I have used it as for bass), it is assignable on Juno-106, so it can be chosen if it is just some couple cents or whole octave, and assigned to DCO or LFO, or filter. So, I guess perhaps it is with Juno-60 too if the pitch bender assignment fader for DCO is at the max level.

[ian wheele]

Hi jxalex, thanks for the reply , the pitch bend range is assignable on the 60, think I should give the dco slider a clean and see if it makes any difference.
Regards Ian. .

[sepulchre]

I know this is a bit late, but . . . .
I didn't like the pitch bend range either. After some research I found that if you take the bender housing loose (4 screws on the bottom of the case) you can get to some variable resistors - the kind you use a screwdriver to adjust. I set mine so it bends up an octave. It doesn't bend down quite that far but this was many years ago and I don't recall everything. It's easy to find and adjust but be Very careful not to short out anything while adjusting. I think I made a screwdriver from a Popsicle stick to avoid problems.
Hope this helps.