My Sony clock looses 10 minutes every hour, I ourchaed in in teh US and am working thru an adaptor which gives an output of 110-120 volts. can anybody of any help?
Dont think this model clock accuracy depends upon the supply frequency.
1. I have ICF C 318 with the same specification but works accurately (1 sencond) in 50 Hz.
2. there are some amazone complaints even from US (wherein 60 Hz exists)
3. Dont think a clock designer will depend on supply frequency. (many time, this varies even in a very good power network)
Posted on Oct 10, 2008
Hello everyone,
As danycrash pointed out, it depends on the supply frequency. But I have the solution now. Do the following carefully. Before starting note that the stupid designer of this clock assumed that we are having a pure sinewave powersupply with constant frequency and even without any power failure. So my solution (I found out by doing some research on this :-) ) will work if you can guarantee continuous 50 HZ power supply That wont be possible in india I am sure.
1. Open the box (you got 5 screws to remove , two of them hidden behind a body coloured lid at the top).
2. Carefully open the case without damaging the switches and dials and other radio settings (remember this is Chinese made).
3. Now you need to remove one screw (a black one) to take the circuit board out(with the LED panel).
4. If you turn the pcb , you can see two ICs on it . One among them is sanyo ic Number LM 8562. This is one which controls the clock functionality of the device.
5. Now you need a little bit of skill. You need to disconnect the Pin number 26 ( if you are not sure how to count the pins of an ic, observe the IC from top so that you can read the
Part number written on it and from left to right its the third pin on the top line of this 28 Pin IC) . By using a wire cutter with sharp tip, carefully select that pin and disconnect it.
(you can desolder it and pull also if you know how to use a soldering iron) using a nose plier pull the pin and bend it sidewards.
6. now the IC is in mode 12 Hr with 50 HZ. If you want to make it 24 Hr , then you need to ground the pin instead of openig it. I didnt try this.
7. So carefully replace the PCB and the device back cover with properly screwed in.
Now your clock is synch with Indian power supply of 50 HZ ( remember you still need to used 220 to 110 volt adapter) .
Since our power supply varies from 48 Hz to 50.5 Hz, you can expect the clock may lag around 1 minutes per hour. If you have an invertor with 50 HZ constant supply,
then it should be accurate.
Even in US, the supply frequency varies. I dont know why the circuit designer did like this.
I have another one ICF-C318, which is accurate till today ( guess its using normal clock ciruits not depending on the power supply)
Hope your device is working fine now.
regards,
Anand KRishnan
Bangalore
×
Hello. I had the same problem, i found the solution. the clock is prepared to work on 60hz power network and you may have a 50hz one. It is possible to modify knowing a bit of electronic.
Posted on Jul 17, 2008
550 views
Usually answered in minutes!
Thanks Arpi...
My Sony Clock IC492 looses 10 minutes every hour, I purchaed thru Amazon.com in Feb-2008 in US and am using it thru an adaptor which gives an output of 110-120 volts from 220V.
Can anybody help me please?
I have the same problem. I dont think it is because of supply frequency. Since I have another clock radio model number slighly differ ICF C 318, its accurate for even 1 seconds. So how come only ICF C 492 clock depends on the supply frequency? I guess internal circuit use the DC voltage after rectifying the AC. And some amazone complaints looks like this is happening in US also wherein 60 HZ supply exists.
dont know what to do. Need to find an expert in circuit tracking and fixing.
My clock is going too fast. Every day it goes about 20min early. My voltage and frequence are 127ac~60Hz, the right one to this clock. This problem started 6 months after I bought it.
Hi,
Anand krishan given a good solution for this but later in the end of his comments he said it again lags 1 min for 1 hr so finally 24mins in a day then what is the use of disconnecting the 26th pin in IC. Can u please be clear in what u said. Does it really works without harming the clock functionality.
Can we try your suggestion without fear.
My clock is going too fast. Every day it goes about 20min early. My voltage and frequence are 127ac~60Hz, the right one to this clock. This problem started 6 months after I bought it.
×