Kenwood KR-5600 Capacitor Project

I bought a little Kenwood KR-5600 yesterday at an estate sale, and in the process of cleaning it up noticed that it had a capacitor that had leaked (picture attached). The board seems to be in the power section as it sits just above the main filter caps and looks to be the first connection to the transformer. I'm trying to find the correct capacitors (7 of them to replace), but am having problems finding them and could use some help finding the right caps and a supplier. This board looks like it has been hot in the past and I would like to find some 105 caps if I can find them.

The existing caps are as follows following;

5 - 25v 100uf (originals are Rubycon)
1 - 16v 220uf
1 - 35v 100uf

Thanks in advance for the help!:thmbsp:

From the picture, it doesn't look like the capacitor leaked, might just dried glue that fell on the cap when they were gluing down the caps prior to the wave soldering.

Those are common value caps and yo can get from Mouser or Digikey, you can increase the voltage rating of the replacement caps without any problems, e.g., 25 or 35V instead of 16V.

I've been on Digikey and Mouser and must admit that I really don't know how to navigate the multiple search components when looking for these caps - I know what uf I am looking for and voltage, but could use some help on the other attributes to use in the search engine to find replacements for these or what brand would be best for this project. Some "coaching" would be greatly appreciated!

i would suggest replacing all six 100uf caps with Nichicon PW 100uf/35v, Mouser Part #: 647-UPW1V101MPD.

For the 220uf cap you could go with this, Mouser Part #: 647-UPW1E221MPD

There are lots of other options, these are common sizes and voltages.

39cross said:

i would suggest replacing all six 100uf caps with Nichicon PW 100uf/35v, Mouser Part #: 647-UPW1V101MPD.

For the 220uf cap you could go with this, Mouser Part #: 647-UPW1E221MPD

There are lots of other options, these are common sizes and voltages.

Click to expand...

Thanks for the recommendations!

I agree with 39cross, Nichicon PW (aka UPW). To navigate to these parts starting on Mouser's home page you would follow this path:

passive components>capacitors>aluminum electrolytic>leaded>

which would get you to the part selection application where there are many more options. Termination style of these caps is radial. Voltage and uF you also know.

You can narrow the selection by brand. Commonly recommended caps for this type of application are Nichicon PW and Panasonic FC or FM. It is good to go with brands/models that are well known on AK and frequently discussed. Also, all of these are 105C rated, which means they should be more durable than the 85C originals.

Once you find the PW (or FC, FM) caps with proper uF and voltage, it is possible you will have a choice between different lead spacings, in which case choose to match your originals if possible. If you need to go up a step in voltage that might help you match lead spacing. Lead spacing is not critical, though, just makes for a little bit neater job if you can match the original.

Be aware that new electrolytic caps will be smaller than the originals of similar specs.

roger2 said:

I agree with 39cross, Nichicon PW (aka UPW). To navigate to these parts starting on Mouser's home page you would follow this path:

passive components>capacitors>aluminum electrolytic>leaded>

which would get you to the part selection application where there are many more options. Termination style of these caps is radial. Voltage and uF you also know.

You can narrow the selection by brand. Commonly recommended caps for this type of application are Nichicon PW and Panasonic FC or FM. It is good to go with brands/models that are well known on AK and frequently discussed. Also, all of these are 105C rated, which means they should be more durable than the 85C originals.

Once you find the PW (or FC, FM) caps with proper uF and voltage, it is possible you will have a choice between different lead spacings, in which case choose to match your originals if possible. If you need to go up a step in voltage that might help you match lead spacing. Lead spacing is not critical, though, just makes for a little bit neater job if you can match the original.

Be aware that new electrolytic caps will be smaller than the originals of similar specs.

Click to expand...

Thanks Roger, this is EXACTLY the help I was hoping for in navigating Mouser - I really appreciate it!

I'm gonna roger what roger2 said...he filled it all in. I'll just add extra thoughts.

Sometimes I use the search feature and type in the brand and type, such as "Nichicon PW" or "Panasonic FM", for example. Also check the "stocked" check box, then click the search icon (magnifying glass). Next click on "Aluminum Electrolytic Capacitors ". This will return a list of the choices for that particular type, and you can filter to get specifically what you want. You want radial caps, as roger2 says. If you run through this using Nichicon PW and filter on 100uf and 35v, you will see three choices. You will want the 3.5mm lead spacing, I think I would choose the bulk packaging, other packaging choices deliver the caps in paper rolls which are used in automated processes. You can still use these, but it's easier to use bulk, these will come separated in a neat little plastic bag.

Good luck with your project! I took a quick look to see if I could find the service manual, but didn't find it, though it is probably out there. You may want to replace all of the caps in the power supply section if you can get to them, that is likely to make it sound better. In for a penny, out for a pound

If you have more questions please post away. It is confusing at first, for sure.

This is a nice size project for a first time replacing caps.

Conventional wisdom would be to replace just one or two caps then test. But in this case I would suggest doing all 7 at once if you are confident in your soldering skills. The reason I say this is you have lots of wire-wrap connections on at least two ends of this board. Access to the under side will be a little tricky. Those wires are delicate and will break if bent too many times due to flipping the board over repeatedly. I experienced this when re-working a difficult to reach board on my KA-4006.

Make sure that you have pics showing +/- orientation of all the caps before removing them (or draw a picture). And when finished be sure to check for any solder bridges, remove excess flux, and verify that all of the wires are still intact and connected.

Yes, as roger2 says take a picture or make a diagram before you start work on the board, it's amazing how quickly you can forget what went where after you remove stuff from a board! That tip cannot be overemphasized.

These being electrolytic caps they will have + and - leads. The positive lead will be the longer lead. There will be a stripe on the side of the cap with the negative, shorter lead. Sometimes the board is marked as to positive/negative connections, but sometimes not. Make sure you have this referenced before you start removing caps.

Thanks Roger2 and 39cross, its people like you two that make AK so awesome. Yeah, I must admit those wire wrap-wrap connections make getting to the underside of this little board a challenge, but like both of you have said - this is a good project to hone my skills on!

What I do is look at the data sheet for the basic specs I'm looking for.

So lets say you were looking for a Nichicon PM part, the big brother of the PW series. In the mouser search box type [ Nichicon PM 100 uF 35 V ] , the spaces help the search function find the parts.

This will basically work with any capacitor they carry. If they don't carry that particular line it will come back with tons of gibberish as suggested options.

Data sheet for PM series.
http://www.nichicon.co.jp/english/products/pdfs/e-pm.pdf

Another thing you want to keep in mind is the dimensions of the can/case and the lead spacing to make sure they will fit properly in place of the old capacitors.