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2230 recap

Just pulled the board down to have a look at it and the part list. Funny you mention the Munsdorfs. It was the only ones I hadn't ordered and thought I will have to get those at Parts Connexion on Monday after work but if it's not necessary then maybe I won't bother. An Oscope was the next on the purchase list for me but a Mint 2245 got in the way yesterday so Oscope will have to wait I guess. Thanks for the advise.
 
Got most of the Wima Film done. Very time comsuming process extending the leads etc . Started the transistor replacement but I hit a snag with the silk screen printing whereby the numbers on H402 are printed twice once on each side ( so H401/402 ) on the right side and ( H403/402 ) on the left side. The SM has H401/403 on the right side and H404/402 on the left side , so I shut it down for the night. Start fresh in the morning. I think I have one location with the wrong transistor as a result. The parts list has two different transistors with different values for these locations so want to make sure not to mix them up. Grrrrrr.
 

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Oh, forgot about that hot mess. Took me a while to figure out that all odd numbered transistors are on the side next to P400 and even are away from it. The two sides are mirror images. On the end nearest P400, H401 is marked correctly and the one near it marked H402 should be H403. On the end away from P400, H402 is correct, and the one marked. H403 should be H404. Good looking work, BTW. I am having second thoughts about those green caps at C401/402. If you don't want to spend $16 on two caps, and if we follow the MBuras rule of replacing the big greenies, you could probably use something like this.
http://www.mouser.com/ProductDetail...GAEpiMZZMv1cc3ydrPrF%2bfZ13WJ/r1/TbbYpNpdX6o=
 
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I figured I'd better leave it alone when tired. More chance to mess it up. I also remember about those big greenies however I have nothing to order from Mouser at the moment to warrant the $ 20.00 shipping cost for 2 of the $.95 film caps. I tried to find something on the Parts Connexion site because I could pick it up local on my way to work next week but also had no luck finding it. I find the Mouser site much better than Parts. Maybe I'm doing it wrong. At any rate thanks for the clarification on the transistor mess.
 
Dearslayer said:
Got most of the Wima Film done. Very time comsuming process extending the leads etc .
Click to expand...

To obtain Wima MKS2 capacitors with longer leads, order in "ammo" or "tape" packaging.

WIMA MKS2 1µF: http://ca.mouser.com/ProductDetail/...=sGAEpiMZZMv1cc3ydrPrF7l45uRd9dVh4k4wYzb/PR0=

WIMA MKS2 3.3µF: http://ca.mouser.com/ProductDetail/...GAEpiMZZMv1cc3ydrPrF7l45uRd9dVhS1mI%2bXFtI9M=

Steven Tate said:
...I am having second thoughts about those green caps at C401/402. If you don't want to spend $16 on two caps, and if we follow the MBuras rule of replacing the big greenies, you could probably use something like this.
http://www.mouser.com/ProductDetail/Panasonic/ECQ-E4224KF/?qs=sGAEpiMZZMv1cc3ydrPrF%2bfZ13WJ/r1/TbbYpNpdX6o=
Click to expand...

For the capacitors, C401/402, in the input high pass filter, a polypropylene type (better dielectric than polyester) can be used; also its capacitance should be increased to at least 0.47µF to obtain a F3 of <5 Hz. For example, this Panasonic ECW-F2 type would be a good choice: http://ca.mouser.com/ProductDetail/...EpiMZZMv1cc3ydrPrF%2bsu0%2bUU4qEgZe1Ftr3eLbM=
 
Thanks Leestereo.... I will have to leave them for now unti I place another order with Mouser. Do you know if Parts Connexion would have an equivalent for C401/402 that way I could just pick them up istead of paying the $20 shipping charge for a $3.00 order.
 
Very good to know. I've been wonderingwhat was a cheaper alternative replacement other than the Mundorfs. Also hadn't heard about upping the capacitance. Thanks!
 
Steven Tate said:
I've been wonderingwhat was a cheaper alternative replacement other than the Mundorfs
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MBuras said:
And I thought you might want to include a budget option for those Mundorfs at C401/402. These [667-ECW-FD2W224JB] would probably make a nice substitute at a fraction of the cost.
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From your 2245 rebuild thread. :biggrin:

The capacitance trick is new and I would certainly trust any advice @Leestereo gives. :thumbsup:
 
Well I've run into a problem. I had sound before attempting the 400 board and now after completion I have no sound at all. I did correct one transistor at H404 that I had in reverse, but still no sound at all on any input. Any suggestions besides the obvious of checking polarity and lose wires.
 

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Did you replace H408? I'm only looking on a phone so can't see it very well. Make sure it is oriented correctly. Also look for anything on bottom that might be shorting to chassis
 
Yes replaced all 8 transistors on that board. As I noted earlier I did have one in backwards but I corrected it and thought that would do the trick but no luck. I checked orientation of the others as well but they are installed ECB as well I can tell. I removed the board to check under but nothing I can see out of the ordinary. I had the tone controls out while doing the board to allow a bit more slack so I checked those wires as well in case something came loose but all seems ok. Polarity on the electrolic caps seem correct. It has me stumped.
 
Hope some experts will check in. I'm reaching now but saw a thread the other day where things went south after board work and it was one of the wires that was stretched while getting to back of board. It broke inside insulation. Check all wires to the board closely.
 
How would I be able to tell if a wire is broke inside? I do admit there was quite a bit of bending back forth to access desoldering and soldering again so it's possible.
 
Also I wonder if that Transistor that I had in backwards is any good now once I reinstalled it correctly. Could it have blown on power up if it was in backwards?
 
You could use a continuity tester and touch both ends of each wire. But first I would replace that transistor.
 
Dearslayer said:
Ok. I will try. Not sure if I have an extra new transistor but if not I can install the old one or test purposes.
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Good idea. Hope you can tell which one came from that slot. I think there are two different transistors among the eight....right? Here's hoping that is the problem. Hard to figure what could knock out all sound by working on the 400 board when everything looks so good.
 
I think I do actually remember which one came from that slot. Process of elimination right. Fingers crossed that's all it is,only I have a nagging feeling it isn't.
 
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