Marantz 2230B Recap Project - Started

[KutzlerTrans]

I had problems before i bought a good solder station by using one of these I left a few Asshole Tracks in a nice 2330 amp board by lifting a few copper tracks with one of these.
Now i have nice temp adjustable solder station, i run about 400 degrees. .031 Kester44 solder.

 

[KutzlerTrans]

Find the Blob style diode...

 

[rBuckner]

The one on the left?!

 

[bgorman]

Which one of these diodes just doesn't belong...... Good stuff! Thanks for the photos. Wasn't sure if "blob" was a technical term or description of how it looked. Know I now.

A little bummed as I'm getting into this 2230B noticed the back corner of the unit/chassis is bent. Looks like it was dropped or hit hard. The corner of the Tuner board is cracked off. Oh well that's the chance you take buying off ebay. It did work prior to disassembling so that's my bright spot.

Thanks to all for the soldering tips including "Dingman" solder joint should be 5 seconds max. John, can't imagine you used that ( hog iron ) to many times before thinking there has to be a better way. I'm actually pretty decent at soldering one of the reason I even took on this project.

Randy back to the differentials. Just getting to the amp board noticed that the Diff transistors are not shrink wrapped together or for that matter even close to each other. Did Marantz shrink them together originally???

 

[Dingman]

I had problems before i bought a good solder station by using one of these View attachment 661140I left a few Asshole Tracks in a nice 2330 amp board by lifting a few copper tracks with one of these.
Now i have nice temp adjustable solder station, i run about 400 degrees. .031 Kester44 solder.

That cracks me up, I tried the same type of iron initially. I burned up a few things before I went to an underpowered Weller. Obviously that didn't work well and so also got the the Hakko 888-something-something. With the Hakko, I can actually get the solder to do what I want it to do.

But the brings up another question. I like to heat fast, get it done and run the iron around 6-700° F. KutzlerTrans, you're running 400°? I have a hard time getting a fast solder transfer lower than 700 or so. Do you have any thoughts on that? Tip variation, and maybe pressure applied could account for some differences.

Oh boy, I'm getting deep in the weeds now, this is what happens when I have couple beers with friends after work, but before dinner. Whoop!

 

[KutzlerTrans]

In china, they can push the knob on were ever it will fit the splines, so the correct temperature is hard to say. the dial says 400. .031 solder melt faster than the thick stuff also.

 

[rBuckner]

Randy back to the differentials. Just getting to the amp board noticed that the Diff transistors are not shrink wrapped together or for that matter even close to each other. Did Marantz shrink them together originally???

Well usually but not on all models. I thought you had already seen them that way on yours. If they're not set up to heatshrink together then it doesn't need done. I still recommend Hfe matching them if you have that meter function.

John's picture of the blob shaped diode reminds me to suggest using the meter's diode check function to see what the voltage drop is before removing each one. Most are around 1.2V and so will need two 1N4148's in series like John's picture shows. If it's around 0.6-7V just use one.

Soldering temp is a matter of preference and I like them hot, 600-700F on an adjustable unit. My station is just whatever the tip model does. After awhile you will get a feel for how to do it. As my wise father-in-law once said, "It's not the tool, it's who's holding it". You won't need much pressure! I usually put the tip on and start the solder flow on the tip near the contact point and then move it onto the two items being soldered. That gets the flux flowing, breaking down the oxides and the heat transferring much more efficiently. I like .031 solder for general work too and .015 for surface mount soldering.

 

[bgorman]

Well usually but not on all models. I thought you had already seen them that way on yours. If they're not set up to heatshrink together then it doesn't need done. I still recommend Hfe matching them if you have that meter function.

John's picture of the blob shaped diode reminds me to suggest using the meter's diode check function to see what the voltage drop is before removing each one. Most are around 1.2V and so will need two 1N4148's in series like John's picture shows. If it's around 0.6-7V just use one.

Soldering temp is a matter of preference and I like them hot, 600-700F on an adjustable unit. My station is just whatever the tip model does. After awhile you will get a feel for how to do it. As my wise father-in-law once said, "It's not the tool, it's who's holding it". You won't need much pressure! I usually put the tip on and start the solder flow on the tip near the contact point and then move it onto the two items being soldered. That gets the flux flowing, breaking down the oxides and the heat transferring much more efficiently. I like .031 solder for general work too and .015 for surface mount soldering.

Thanks, Randy
After looking back at "Cowdogs" before photos, it doesn't appear that his were heat shrunk together either. I think I have a decent understanding of these now, one last question, would heatshrinking them together improve performance or at the very least (not hurt the performance)???

Also, great tip on checking the original diodes first wouldn't have thought of that. I noticed on "Cowdogs after photo that he heatshrunk his new Diodes as well. Is it feasible that it would improve performance or is that overkill???

 

[Dingman]

Thanks, Randy
After looking back at "Cowdogs" before photos, it doesn't appear that his were heat shrunk together either. I think I have a decent understanding of these now, one last question, would heatshrinking them together improve performance or at the very least (not hurt the performance)???

Also, great tip on checking the original diodes first wouldn't have thought of that. I noticed on "Cowdogs after photo that he heatshrunk his new Diodes as well. Is it feasible that it would improve performance or is that overkill???

I've only heatshrinked over the dual diodes for appearances, no functional difference.
I can't see any harm in heatshrink over the transistors, and might keep them sync'd up a little better but since they weren't heatshrinked originally, I have no idea if that would result in an audible difference.

 

[rBuckner]

I agree with you Dingman. It won't make an audible difference to heatshrink the diff's together but will improve thermal stability a bit. If it can cause the legs of the transistors to be stressed by weird bends that wouldn't be good. You may need to put some sleeving on to prevent shorts too. It's not the heatshrink itself that is helping, it's that it is drawing the two transistors together and thermally coupling them with the aid of the thermal paste. Don't use the silver paste by the way!

 

[bgorman]

Thanks to both you guys. That makes sense to me.

It also seems like if they are heatshrunk together and operate at the same temp. that they would also age equally. Maybe??? Theory and reality don't always meet!

 

[bgorman]

So, I bought 3 marantz units (overpaid for all of them) The marantz 2220B that I already re-caped and enjoying listening too, the 2230B I'm currently working on and another 2220B I bought because the Faceplate and knobs were mint (still had the protective cover). Its been sitting. Decided to take a closer look last night and noticed a couple of things. When I opened it it look different. I started comparing to my other 2220B and noticed it didn't have the P300 Board (MPX stereo) Some of the other boards were different as well. I looked at the plate on the back and it reads Marantz 2220B (c)

Does anyone know what the (c) means, I'm thing Canada but not sure??? And does anyone the differences between them??? Without the MPX board does it still recieve in Stereo???

Probably wouldn't have bought this unit had the listing said it was a (c), but own it now. Also need to find a service manual for it.

 

[rBuckner]

They're all pricey these days! I love the sound of a 2220B so great choice IMO. Bummer about the MPX board but they can be had used. So is there wiring hanging out where it was? If it was bought on eBay, did they disclose the missing board? If not, you may be aboe to return it as "not as advertized" no matter what the seeler's return policy is. I doubt you'd even hear the FM with that board removed. If it was never there, well, I've not heard of that situation. I believe you are right that the "C" is for Canada models. The schematic will tell you of differences and what I remember is that it's usually only mains power input stuff.

The manual is here: http://akdatabase.com/AKview/albums/Marantz/Marantz 2220B Service Manual.pdf

 

[bgorman]

They're all pricey these days! I love the sound of a 2220B so great choice IMO. Bummer about the MPX board but they can be had used. So is there wiring hanging out where it was? If it was bought on eBay, did they disclose the missing board? If not, you may be aboe to return it as "not as advertized" no matter what the seeler's return policy is. I doubt you'd even hear the FM with that board removed. If it was never there, well, I've not heard of that situation. I believe you are right that the "C" is for Canada models. The schematic will tell you of differences and what I remember is that it's usually only mains power input stuff.

The manual is here: http://akdatabase.com/AKview/albums/Marantz/Marantz 2220B Service Manual.pdf

Thanks Randy
I actually have a download of the 2220B manual.

Wow am I confused. The board I'm referring to isn't the (MPX board) it's a (Dolby board) PC01. This board does not show up in the 2220B manual at all, neither in the pictorials or the individual board component layouts. It does however show up in the 2230B manual.

My standard 2220B has this board, but the 2220B (c) model does not. Not even an opening or wiring for it. So to answer one of your questions its not missing, it was never there to begin with. I will take a closer look this evening to see what other differences there are, but I'm convinced this is a Canadian model. Not sure I'm all that happy about that or if I can get a manual that's specific to it. Bummer

 

[rBuckner]

Thanks Randy
I actually have a download of the 2220B manual.

Wow am I confused. The board I'm referring to isn't the (MPX board) it's a (Dolby board) PC01. This board does not show up in the 2220B manual at all, neither in the pictorials or the individual board component layouts. It does however show up in the 2230B manual.

My standard 2220B has this board, but the 2220B (c) model does not. Not even an opening or wiring for it. So to answer one of your questions its not missing, it was never there to begin with. I will take a closer look this evening to see what other differences there are, but I'm convinced this is a Canadian model. Not sure I'm all that happy about that or if I can get a manual that's specific to it. Bummer

It is Canadian then. Canada wisely didn't fool with the short lived Dolby encoded broadcasts so those models didn't need the Dolby board. I'd bet there isn't a separate user manual and I know the Canadian differences are just noted on the USA/Canada schematic. So I'd say just enjoy it, any differences won't affect the way it's used.

 

[bgorman]

It is Canadian then. Canada wisely didn't fool with the short lived Dolby encoded broadcasts so those models didn't need the Dolby board. I'd bet there isn't a separate user manual and I know the Canadian differences are just noted on the USA/Canada schematic. So I'd say just enjoy it, any differences won't affect the way it's used.

Randy
That makes sense about the Dolby and once I get to refurbishing that unit I'm sure I will enjoy it just as much as the other one. Your probably right about the manual to. I assume by your comment that they aren't using the Dolby encoding in Broadcast anymore???

On another note, I finished the re-cap on the Tone, Phono and Pre-amp boards on my 2230B, cleaned this filthy unit inside out, installed the new LED light kit and did a full cleaning of the tuner, re-assemble for a test run and I couldn't be happier. I can't believe how much bigger the sound is from this unit versus the 2220B I re-furbed. Not to mention the FM signal is unbelievable considering I'm using only speaker wire as the antenna, in my basement, roughly 40 to 50 miles from most of the radio towers and almost all of them in Stereo. If anyone is considering cleaning the tuner in these things you have to check out the Thread for that here at AK. All the info you need is there. Well next up will be the amp board and the filter caps, but so far couldn't be happier with this unit. Thanks to you and John and all the others for the great advice.

 

[rBuckner]

Correct, no more Dolby since the last half of the '70's sometime. Glad you had success, be proud of yourself and enjoy!

 

[bgorman]

Correct, no more Dolby since the last half of the '70's sometime. Glad you had success, be proud of yourself and enjoy!

So does the Dolby board do anything?

For reference I attached photos of the Plate on the back and the Inners of what I assume is a "Canadian" model 2220B. Not sure if it will be helpful or not. You'll notice that there isn't even an opening for the Dolby board. The other thing I noticed is that the Main amp board has few components on it overall. Don't know if that's good, bad or indifferent just some of the differences.

 

[rBuckner]

Yes it will. What Dolby encoding does basically is to boost the high frequencies, and decoding that the Dolby board in your USA 2220B does is to de-emphasize those high frequencies to bing the response back to flat. There was no pilot tone or indicator of any kind done in the encoding so decoding circuitry has no detector of any kind and just "blindly" does it's work so it will bring down your high frequencies anyway.

On the amp board, are you saying one version has more parts on it than the other? That would not be what I'd suspect. If that's what you mean shoot us some pics, 'twould be interesting! But if it works fine it has all it needs, right?

 

[bgorman]

Yes it will. What Dolby encoding does basically is to boost the high frequencies, and decoding that the Dolby board in your USA 2220B does is to de-emphasize those high frequencies to bing the response back to flat. There was no pilot tone or indicator of any kind done in the encoding so decoding circuitry has no detector of any kind and just "blindly" does it's work so it will bring down your high frequencies anyway.

On the amp board, are you saying one version has more parts on it than the other? That would not be what I'd suspect. If that's what you mean shoot us some pics, 'twould be interesting! But if it works fine it has all it needs, right?

Interesting info on the Dolby encoding and the Dolby board function. Justed wanted a better understanding, great layman's explanation The push button "Dolby Fm 25us" increases the highs. When its used, is it essential disengaging the Doldy Board function ???

And yes on the Amp board, between the USA & Canadian version. At a glance last night the Canadian version looks less crowded. However the main components seemed to be the same. I don't have the Amp boards out but will get as good of photos as I can of both & post. The Canandian 2220B was the third unit I bought, so I haven't really gotten into it it yet, just pulled the cover and glanced around inside. I did of course hook it up to speakers to make sure it worked and it did.

It will be an interesting comparison once the other is Re-furbished to see how the 2 compare in sound, one with the Dolby board the other without, but that will easily be January since I still need to finish the 2230B and with the Holidays approaching.