Fishman Fluence Universal Battery Pack MOD

[nosaj]

The Dude brought up some excellent points in his post that I had not considered.
If I get a chance this weekend I'll string up some diodes to see how many we might be looking at.
Another thing I am curious about is how is this going to connect to your pickup. If it were a Fishman FLuence it would be plug and play.
nosaj

[nosaj]

https://www.amazon.com/KNACRO-12V-6V...language=en_US

doesn't that mean it would run fine off of 9V ?

A bit overkill

nosaj

[h31k0]

A bit overkill

nosaj

hehe, alright. but reading

Protection: Input instant high voltage, output over-current, output short circuit, chip overheating protection.

sort of calms me ^^

I also found this regarding input voltage:
https://www.amazon.com/DROK-Waterpro...dp/B00C0KL1OM/


/Edit: I don't mind investing some extra bucks for "extra protection".

[h31k0]

The Dude brought up some excellent points in his post that I had not considered.
If I get a chance this weekend I'll string up some diodes to see how many we might be looking at.

thanks a lot for that offer nosaj! that's very kind of you. :-)

Another thing I am curious about is how is this going to connect to your pickup. If it were a Fishman FLuence it would be plug and play.
nosaj

that is a very good question indeed. I was thinking of soldering onto the little battery holders but I fear two things:
1. how to figure out where + and - are? because with some devices the CR2032 connects through its top and bottom and in others through the "sides"...
2. through the solder iron heat I would apply a lot of "voltage" to the pickup directly, right?
even if it's just for a couple of seconds that could be too much for the pickup and fry it?
(please forgive me naive electronic skills)

do you have any suggestions as of how to connect to the pickup ?
maybe via CR2032 "dummy" batteries?

[nosaj]

How about some pics of what we are looking at on your guitar?
nosaj

[The Dude]

alright! since you both suggest a zener diode would do the job I shall go for this but I have some questions
(sorry for asking but I fear my knowledge of circuits and soldering are too basic to figure it out myself):
1. would that zener diode be sufficient? if not would you be so kind to suggest a different one please?
https://eu.mouser.com/ProductDetail/...MoPDqcFQ%3D%3D

2. with "insert into the voltage path" you mean to solder it here?

I didn't suggest a zener diode. In fact, DO NOT simply solder a zener diode across the existing supply! You may damage the supply by clamping it's 9V output to 6V. I am talking about standard diodes in series with the positive supply out- for instance the common 1N4007. A common diode voltage drop is roughly .5V to .7V and varies from manufacturer and even batch. You will have to measure as you add diodes to be sure what the output voltage is.

[The Dude]

thanks for the detailed explanations The Dude! :-)
could you hint me to an applicable "series diode" (at mouser or similar) ?

as to point 3) how about this one here?
https://www.amazon.com/KNACRO-12V-6V...language=en_US

doesn't that mean it would run fine off of 9V ?

Here's a link to suitable diodes. You wouldn't need anything rated that high for this purpose, but they are common and cheap.

https://www.mouser.com/ProductDetail...U1uTiCkg%3D%3D

Looks like that step down supply would work, but it's more expensive and larger than a small hand full of diodes.

[h31k0]

How about some pics of what we are looking at on your guitar?
nosaj

here you go ;-)

https://ibb.co/THt1rjs
https://ibb.co/N7Cvd5N
https://ibb.co/nwFGvRK

my mobile is pretty old and not the best. sorry for the blur/haziness.
let me know if you need more photos.

[h31k0]

I didn't suggest a zener diode. In fact, DO NOT simply solder a zener diode across the existing supply! You may damage the supply by clamping it's 9V output to 6V. I am talking about standard diodes in series with the positive supply out- for instance the common 1N4007. A common diode voltage drop is roughly .5V to .7V and varies from manufacturer and even batch. You will have to measure as you add diodes to be sure what the output voltage is.

alright, gotya! :-) I won'T solder directly to the supply but rather do what you suggested before. I'll get some 1N4007 diodes, wire them in series. you say with the positive supply out ?
what does that mean exactly? so inserting them like so:
V+ (red cable supply output) --> diode1 neg. --> diode1 pos. --> diode2 neg. --> diode2 pos. --> etc. ?

Here's a link to suitable diodes. You wouldn't need anything that rated that high for this purpose, but they are common and cheap.
https://www.mouser.com/ProductDetail...U1uTiCkg%3D%3D
Looks like that step down supply would work, but it's more expensive and larger than a small hand full of diodes.

thanks for the link, will use these.
alright seeing that both of you suggest that the step down is overkill/expensive for the job I'll go with the diodes in series.
I'm also shying away from this particular step-down after reading people's comments/reviews on amazon.
It brings up a general question (again possibly a naive one): will the diodes-in-series "increase/create heat" ?
and how reliable will they be, e.g. what happens if one or multiple suddenly die? then voltage might go over 6v which might damage/fry the pickup?

thanks again for all your help, explanations and efforts with this. I highly appreciate it!! :-)

[h31k0]

sorry for the continued input but I just came across this and wanted to run the idea by you.
What about using an IC like here?
https://www.circuits-diy.com/9-12v-t...-using-lm7806/

[The Dude]

Here's a quick rough schematic. Again, number of diodes may be different.

[The Dude]

sorry for the continued input but I just came across this and wanted to run the idea by you.
What about using an IC like here?
https://www.circuits-diy.com/9-12v-t...-using-lm7806/

The problem with the 7806 is that it likes at least 11v input. Even if we assume it will work with 9v, what happens when your battery starts to go low?

[h31k0]

The problem with the 7806 is that it likes at least 11v input. Even if we assume it will work with 9v, what happens when your battery starts to go low?

gotya! then no ic it is in our case :-P

Here's a quick rough schematic.

thanks for the schematic. that clarifies it for me :-D



OK. I'm gonna get my hands onto these diodes, get a fresh 9V battery out
(as I do not have the Fishman 9v battery charger with me yet) and start testing.
be back here asap.

[The Dude]

......It brings up a general question (again possibly a naive one): will the diodes-in-series "increase/create heat" ?
and how reliable will they be, e.g. what happens if one or multiple suddenly die? then voltage might go over 6v which might damage/fry the pickup?......

The 1N4007 is a 1,000V 1A diode. It won't get hot or fail in this low current- low voltage application.

[h31k0]

The 1N4007 is a 1,000V 1A diode. It won't get hot or fail in this low current- low voltage application.

awesome! thanks for the clarification! :-)