KMD GS130SD / Need parts schematics

[glazcon]

I have a KMD GS130SD amp that has been stored in my garage for 18+ years. It powers up, but only the clean channel plays, but at no more than half the volume that it used to! There are two Phillips capacitors, 2200uf 100v 2222 050 59222, One runs out to infinity, but the other runs up to about 430 and stays there (When tested with a DMM). I can not find these capacitors online. Does anyone know where I can find these or can I cross reference with something else? Also I am not sure if this is the problem, but I figured it as a starting point!

[bry melvin]

capacitors don't need to be replaced with the exact item.  just go to Mouser, Digikey or Newark electronics, Antique radio supply. ( or other) and use a capacitor with the same values. I assume from 2200 it's an electrolytic. I prefer Mouser. They have a search that let's you specify values and links to datasheets so you can check physical dimensions.

If one electrolytic in an amp is bad often it is a convenient time to change all electrolytics. The other types seldom go bad with age (except wax and paper covered ones and your amp is way too recent for them)

[J M Fahey]

Did you measure them off board or in circuit?
In the second case some other component may cause that reading.
If you had a bad cap you would have strong hum, or instabilities, but not just "low power".
Those were very well made amps, the ones I remember were hybrid: SS preamp plus a couple output tubes.
Post a couple pictures.

[glazcon]

Thanks for links. No hums. I tested in circuit. One problem I always had with this stack is that the effect loop has to have a cable plugged into it (one cable plugged in both jacks) to make it work. What I call capacitors might be the output tubes you referenced (JM Fahey) My pics are too large to post on this site, even when I zip the file! I could probably email.

[DJPhil]

To easily make pictures from a digital camera forum friendly I use Irfanview. It's free and very useful. Download here.

Here's a short, somewhat half-assed tutorial that assumes some familiarity with computers:

• Copy your pictures to your computer somewhere where you can find them.
• Open with Irfanview. The view controls are under View>Display Options (Window mode), spend a little time getting familiar with them until you can see what you're doing. It often defaults to 1:1, which can be much larger than your monitor (and confusing). The "Fit Images to Window" option is probably what you'll want to proceed with.
• Draw a box around the important parts of the picture and use Edit>Crop Selection (Ctrl + Y). If you framed the shot perfectly then feel free to skip this step, but it can save a lot of space if you just want to show something specific. Don't remove so much that the photo's not useful!
• At this point I usually use Image>Auto Correct Colors (Shift + U). This can help legibility with pictures that have bright borders cropped out. Skip this if it makes it look worse.
• Time to resize. The settings on your camera and the cropping you've done will determine the original size, and it's usually huge. Use Image>Resize/Resample (Ctrl + R). This will open up a box that allows you many ways to choose the final size. Always make sure the "Preserve Aspect Ratio" is checked, as this keeps the image from distorting. I usually just set it to 25% of normal size, but I'm used to how large my pictures come out. You can use the drop down box in the upper right for quick selection, 800x600 should work ok. Using the "Apply sharpen" check box is recommended, as is setting the "Size method" to Resample on the slowest filter (high quality).
• Almost done, use File>Save for Web. This will optimize the picture to take up as little space as possible while still trying to retain detail. All you have to do here is hit the big Save button and it will save a finished copy.
• Double check your new skinny picture by opening it Irfanview. Can you see enough detail when you zoom in to make you happy? Often you don't need much detail to get a point across, so don't sweat it unless you're looking to convey something specific.

Irfanview has all kinds of other options and abilities, and it's definitely worth the investment in time to learn the program if you work with digital images.

Hope that helps

[bry melvin]

Thanks for links. No hums. I tested in circuit. One problem I always had with this stack is that the effect loop has to have a cable plugged into it (one cable plugged in both jacks) to make it work. What I call capacitors might be the output tubes you referenced (JM Fahey) My pics are too large to post on this site, even when I zip the file! I could probably email.

It actually sounds like the first thing you should do with this amp is clean the jacks and pots etc with deoxit( or equivalent) and possibly change the jacks and go from there.