Hi guys. Haven't visited in a while...
I have an old Kenwood turntable with a simple enough power supply that I'm planning to tackle it myself. There is an apparently bad "SCR" that clearly got very hot. I worked with Digi-Key to find a suitable replacement, and I figured I'd replace the rectifier diodes and capacitors while I'm at it.
So, on the capacitors- they are electrolytic, and I found pretty much exact replacements (Nichicon UKL low leakage ones) but I seem to recall it being a good idea to go up on voltage from the original rating? Is that a good idea, or should I stick with exact replacements (or as exact as I can get)?
For example, C1 is 10uF 16V. Should I go with 10uF at 35V?
C2 is 10uF at 10V- and 16V is the lowest voltage rating in this series. Will that be fine, or would I need to seek out a different capacitor for that location?
I have attached the schematic and parts list for reference. I'd like to place my parts order in the next day or two if possible.
Thank you very much!
I have an old Kenwood turntable with a simple enough power supply that I'm planning to tackle it myself. There is an apparently bad "SCR" that clearly got very hot. I worked with Digi-Key to find a suitable replacement, and I figured I'd replace the rectifier diodes and capacitors while I'm at it.
So, on the capacitors- they are electrolytic, and I found pretty much exact replacements (Nichicon UKL low leakage ones) but I seem to recall it being a good idea to go up on voltage from the original rating? Is that a good idea, or should I stick with exact replacements (or as exact as I can get)?
For example, C1 is 10uF 16V. Should I go with 10uF at 35V?
C2 is 10uF at 10V- and 16V is the lowest voltage rating in this series. Will that be fine, or would I need to seek out a different capacitor for that location?
I have attached the schematic and parts list for reference. I'd like to place my parts order in the next day or two if possible.
Thank you very much!
Hi, personally i don't find problem if capacitor is replaced with another one ,having higher allowable voltage. Device is not new, so at production times capacitors was bigger in size,so voltage rating was limited by size and cost. Need to compare other datas of old and new capacitors,but i think should be no problem to put modern ones with low esr and 105c temperature rating. If some capacitors are non-polar, need to look seperately at their replacements.
Size is not an issue. The higher voltage new part size is comparable to the older ones, and it's a pretty wide open board, so I have room for "fudge factor". I just wanted to be sure I wasn't causing problems going up on voltage.
Heat in general should be quite low- but I will be adding a small heat sink to the new SCR just to be safe.
Heat in general should be quite low- but I will be adding a small heat sink to the new SCR just to be safe.
I notice a discrepancy on the schematic compared to the parts list. C2 on the parts list is 10uF 10V and on the schematic it is shown as 33uF 10V. Let me check the picture I have if I can see the value....
C2 does look physically larger in the picture I have... I think the schematic is correct.
C2 does look physically larger in the picture I have... I think the schematic is correct.
You should look what capacity capacitor C2 was installed orginally. According to schematic ,its capacity its not critical ,thats just a small rectifier for thyristor control voltage .
Thank you.
I'll probably put the order together tomorrow. But now I want to check the actual components on the board, since I found one discrepancy already...
I'll probably put the order together tomorrow. But now I want to check the actual components on the board, since I found one discrepancy already...
Hi Jim,
I have a KD-5070 as well. I agree check what is installed on the pcb and replace with what they used. No problem going up in voltage, match the capacity that they used.
I have a KD-5070 as well. I agree check what is installed on the pcb and replace with what they used. No problem going up in voltage, match the capacity that they used.
OK Thank you for the vote of confidence!
So, given the option, you'd go tighter on tolerance, and higher on voltage and temperatures?
So, given the option, you'd go tighter on tolerance, and higher on voltage and temperatures?
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