Crown CSC-935F: How does the battery test work? (new aquisition)

[joebal]

G'day all!

Decided to get an old ghetto blaster, so I got my hands on an $8 fixer upper here, which I have fixed. The left channel was making a weird noise on tape playback (or any tape function). I tracked it down to the long record switch/bar and working that for good 30 seconds/minute resolved it!

I've sacrificed a cordless 20v power tool battery and charger, carved a hole in the battery compartment and hacked it into the unit (there are 5 cells in the pack, so I just tapped the battery after 4 cells in the chain, which gave me around 15v), it's not pretty but it works!! Once the case is closed we'll be none the wiser.



One item that I'm a bit embarrassed to ask about as a techie guy is how the battery level indicator works. I would instinctively look for a button to press, but there isn't one. I cannot find a user manual anywhere for it either....

Thanks all!

 

[goodman]

This is good upgrade. How long can it work with this battery?

 

[joebal]

So far I've been running tapes for maybe 3-4 hours and I think it is still full!

I think I have worked out how to run the battery test, there is a switch on the top of the unit:



It looks like if the switch is on BATT, then I press play on the cassette player, all of the meter LED's light up solid. So I think that is the test there, somebody correct me if I'm wrong!

 

[Superduper]

This is the boombox with the tool battery stuffed in there right? The battery meter, regardless if it works or not, will no longer be accurate and likely always reads full with your 15V cordless tool battery in there. The meter is expecting 12V with full batteries. But at 12V, your tool battery will be totally expended. In fact, when installed in a tool, most tools shuts off the battery to prevent excessive drain which could damage the battery.

 

[joebal]

Thanks Superduper, the battery won't shut off - as I implemented it in an extremely hacky way, by tapping the cells direct, prior to all the circuitry. The tool I sacrificed was a cheap throwaway that was headed for the rubbish pile anyway, so I'm not worried about the battery.

I suspect that I will never use this GB so heavily in a contiguous period of time that I would get to the point of draining the battery all the way down to dangerous levels before periodically plugging the charger in again.

By what you are saying it sounds like I should see a drop in the LED reading once I get below 12v. Maybe we can just say: As soon as I lose one or two LED bars of charge, time to get it back on the charger.

 

[joebal]

An update, so 3 days ago (a good week) after charging it up fully, we finally dropped to four LEDs:



Today the tape playback went silent, so I ran the battery test and it was down to 2 LEDs. Just this once I let it go right down, just for testing purposes. So I think a nice middle ground is once I drop to four LEDs, put the deck on charge. A week of casual use is pretty decent I reckon!