Marantz 2245 has no sound

Ok I did follow that list. Curious , is the phono board needed to be redone if no turntable is connected?
Technically, no. But if you are going to refurbish a unit, why not go all the way? You never know what you might want to do in the future or what a future owner might want. If nothing else, replace the electrolytics and tantalums and the 2SC458's. Maybe an extra hour of time to finish a complete refurbish.
 
Technically, no. But if you are going to refurbish a unit, why not go all the way? You never know what you might want to do in the future or what a future owner might want. If nothing else, replace the electrolytics and tantalums and the 2SC458's. Maybe an extra hour of time to finish a complete refurbish.
I was asking because Digikey didn't have the caps and I didn't want to order just a couple caps from mouser.
 
Those "big browns" are considered very good caps and don't generally need to be replaced. There are only a few electrolytics to replace, as well as two or three diodes and those two 2SC458 transistors.
 
Because I enjoy jumping into things 100% with both feet and I want to absorb the info like a sponge I really need to find some good solid info on 3 things , testing Caps , testing Diodes and testing Transistors. I'm pretty sure from what I've learned about testing the output Transistors that they are either good or bad so thats 1 of the 3 out of the way, I think.
 
Testing a diode is just like testing two legs of a transistor. Diode test function on meter, there should be no conduction one way and a reading somewhere around .6 the other. If current can go both ways, it's shorted. I use one of these cheap Chinese testers to test capacitors, but it also tests hfe and other transistor functions as well as resistors and diodes.

http://www.ebay.com/itm/12864-Mega3...237498?hash=item4af681207a:g:sBMAAOSwa-dWhWzn
 
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That will really be a good meter to have. The cheapie I pointed out is very versatile - works with lots of components - but I'm not sure it tests ESR.
 
Testing a diode is just like testing two legs of a transistor. Diode test function on meter, there should be no conduction one way and a reading somewhere around .6 the other. If current can go both ways, it's shorted. I use one of these cheap Chinese testers to test capacitors, but it also tests hfe and other transistor functions as well as resistors and diodes.

http://www.ebay.com/itm/12864-Mega3...237498?hash=item4af681207a:g:sBMAAOSwa-dWhWzn

This looks like a great little tool to have and I was gonna order one until I just found out it doesn't ship to Canada. Grrrrrrr. I wonder why?
 
This looks like a great little tool to have and I was gonna order one until I just found out it doesn't ship to Canada. Grrrrrrr. I wonder why?
There are several different vendors on the Bay for the same or similar product. Maybe some of the other ones can ship to you.
 
I can't tell for sure. It looks like basically the same setup. It doesn't mention hfe, but I'll bet it gives you hfe when you test a transistor.
 
Ok , that little tool you have is certainly affordable.
Steve what do you use for your solder iron for cleaning the tip? I saw these things that look like a steel wool pad.
Also do you know a trick for tinning the tip, I have no luck at all in that department.
Thanks
Lynn
 
Actually, I use a paper towel. I have one of those steel wool things in the base of the soldering station, but I never use it. After I solder a couple of spots, I pick up a paper towel and wipe the tip off. I use one towel for every sitting and throw it away when I am finished for the session. My soldering tips come pre-tinned so I have never really done anything to them. I use a Hakko 888D soldering station. It has temp control and the tips last pretty much forever. I use a small chisel tip. I think it's 2.4 mm or something like that.
 
I remember my dad always tinning his soldering iron tip. He took a fine file to the flat surfaces and got down to bare copper and then put solder on it before it could oxidize. That's about all I know about tinning.
 
Don't file any modern tips though! There is a plating on them, I think it's iron but could be elementally confused. Filing would ruin it. I prefer a slightly damp sponge but the steel wool looking ones are great too.
 
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