Tivoli Pal battery problem

I just bought a Tivoli Pal radio from ebay.
The problem with this radio is that it can not charge it's internal battery . I checked the battery pack on the back of the unit and did not see any obvious problems. The unit supplies 14.8-15 volts of DC voltage to the battery pack for charging. But the batteries do not charge!

I took a closer look at the battery pack and noticed that something like a big resistor is connected in series between two batteries (of the six). This component has two legs and a metal body for cooling I suspect. It writes KC100oC 250V 5A. Does anyone know what this is? Maybe this is causing the problem. Can I bypass it?

Many thanks
George
 
That will be a 5A fuse.

Fuses come in all shapes, some are axial and look like resistors, some have small square plastic packages that look like poly caps, some are round cans and look like electrolytics.

A new engineer started at work, checking a board.
I asked "have you checked the fuses?"
He replied "what fuses?"
 
I checked the thermoswitch and it has zero resistance. I have left the radio on all night but the batteries have not charged. With the battery pack connected to the radio and the radio is on ac power the batteries show a 2.98volt between their output terminals. Any suggestions?

Thanks again
George
 
I just found out from Tivoli that they have a problem with many Pal batteries. The replacement pack cost 45euros! I have found 8 batteries 1.2v each on ebay for 20$. So I plan to make a battery pack by myself using 6*1.2v AA batteries = 7.2V

The question I have is how to connect the batteries between them to form a pack. The problem is not the orientation of the batteries and their inbetween connections but how does one solder tabs between the batteries. Will my solder gun do? Do I need special equipment. On the battery pack I have I can see that no solder has been used but the tabs have been placed by pressure. I cab see the pressure marks. What shouls I do?

Thanks George
 
It's a fuse, trust me.

While rechargeable cells are available with welded tags to simplify connecting them together to form a battery, I have successfully soldered short wires between them for the same purpose.

First scratch away some of the plating and make it rough. If you don't do this, the solder blobs and doesn't wet the terminals. Then tin the terminal, after which you can solder the wire. I use an 18W Antex iron, and have successfully soldered to "C" size cells with this method, so you don't need a lot of heat, but more heat will help. The cells seem to tolerate this well.

I connect a Schottky rectifier in reverse parallel with each cell, as recommended in an article from Electronics World. The reason given for this is that cells discharge at different rates, and when one is becoming exhausted, it is reverse - biased by the others. This damages the cell, and is of greater importance the more cells there are.

Hope you find this useful🙂
 
I checked the thermoswitch and it has zero resistance. I have left the radio on all night but the batteries have not charged. With the battery pack connected to the radio and the radio is on ac power the batteries show a 2.98volt between their output terminals. Any suggestions?

Thanks again
George
Hi, your post is quite old, but still, Tivoli radios are around the corner!
I had a similar problem with my Tivoli's battery pack and found that one cell showed ~0v (it is easy to remove the pack's plastic cover to gain acces to each cell terminal points). So, I planned to replace only the defective cell with a standard AA/R3 NiMH battery. The most "difficult" part in this operation was the soldering step: just like it is mentionned here by johnnyx, you have to scratch the metal surface before solder the new cell to the metal connectors.
Finally, I used a kind of "rapid fix glue" to glue the new cell to other ones and then replaced the plastic cover and fixed it with scotch rubber. The battery pack was repaired!

However, I face another problem: whenever the battery is charged, the radio won't turn on without the help of the power supply! Moreover, once it is on, I can unplug the power supply and listen to the radio for several hours just using the batteries. Note that my battery pack is now ok and seems to be charged normaly.
So, I think, the problem is only related to the battery charge level detection. Am I clear enough?

Does anyone faced the same issue? The problem might come from a single & simple component (maybe a
damaged capacitor, a zener diode or whatever), but I really don't know yet.
 
Hi, your post is quite old, but still, Tivoli radios are around the corner!
I had a similar problem with my Tivoli's battery pack and found that one cell showed ~0v (it is easy to remove the pack's plastic cover to gain acces to each cell terminal points). So, I planned to replace only the defective cell with a standard AA/R3 NiMH battery. The most "difficult" part in this operation was the soldering step: just like it is mentionned here by johnnyx, you have to scratch the metal surface before solder the new cell to the metal connectors.
Finally, I used a kind of "rapid fix glue" to glue the new cell to other ones and then replaced the plastic cover and fixed it with scotch rubber. The battery pack was repaired!

However, I face another problem: whenever the battery is charged, the radio won't turn on without the help of the power supply! Moreover, once it is on, I can unplug the power supply and listen to the radio for several hours just using the batteries. Note that my battery pack is now ok and seems to be charged normaly.
So, I think, the problem is only related to the battery charge level detection. Am I clear enough?

Does anyone faced the same issue? The problem might come from a single & simple component (maybe a
damaged capacitor, a zener diode or whatever), but I really don't know yet.
Hi NicoLarve, guys. Did you solve the "radio won't turn on without the help of the power supply!" problem. I have one which is doing exactly the same.

I did take the back off a while ago and found that a quick short-cut across two adjacent legs of the three-pin voltage regulator would bring the set on with charged batteries and without the PSU. Now that can't be right, so I wonder if one part of the voltage regulator is blown? But is that really the component that detects the right voltage?
 
I had a similar problem with my PAL BT battery. The radio works great off of its power supply, but the battery charge lasts only 15 minutes then shuts down. When placed back on charge, it goes through the expected sequence of slowly blinking green light and after a period of time, the blinking stops. This would suggest that the battery is charged. But after a period, the green light resumes it's slow blinking. This sequence keeps repeating itself and when the power supply is unplugged and the radio turned on, the battery lasts only 15 minutes before the radio shuts down. Does this sound more like a typical ailing battery that can no longer provide adequate current or is it more likely to be a problem within the radio,'s charging circuit?
 

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