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2235 Transformer

wlhd1610 said:
I don't know if they are similar but I have a working 2225 transformer that you can have.

Bob
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Wow Bob, thanks for the offer but they are different part #'s, 2225 has 35V caps , this one has 50V caps, the part numbers are close but they aren't the same :(.
 
Thanks, the description in that auction, well, it wasn't terribly reassuring. Also, I've really taken to asking whether or not it was used or stored in a smoker's home. In many parts of the country, that may be a given. I've even had medical supplies that reeked of smoke.

If you said the insides of the transformer already look burnt and crispy, I'd have no qualms about dumping the transformer. You cannot tell where there may be a dead short in the windings on either the primary or secondary side.

You'll have to take ohm resistance readings on all windings and then draw them out against a schematic. I don't know whether the 2235 and 2235B schematics are related but I wouldn't count on it. Thanks for uploading to the database.
 
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you could maybe test the windings with a megger if you can find one or have one ..i have one that you have to wind a handle it can be useful on rare occasions .was good for fixing tv picture tubes back in the day
 
mech986 said:
Thanks, the description in that auction, well, it wasn't terribly reassuring. Also, I've really taken to asking whether or not it was used or stored in a smoker's home. In many parts of the country, that may be a given. I've even had medical supplies that reeked of smoke.

If you said the insides of the transformer already look burnt and crispy, I'd have no qualms about dumping the transformer. You cannot tell where there may be a dead short in the windings on either the primary or secondary side.

You'll have to take ohm resistance readings on all windings and then draw them out against a schematic. I don't know whether the 2235 and 2235B schematics are related but I wouldn't count on it. Thanks for uploading to the database.
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Oh you saw it did you. According to the seller it wasn't his, I can tell you it's been into, there are replaced caps on the power board. The transformer always checked out on the secondary side, it was the primary that was botched. Now that the fuse has been removed and is now direct wired I have continuity whereas I didn't before. Cooked- probably not, I guess i'm just not used to tearing apart transformers, it seemed crispy but I tihnk that's just how they are made. There is no evindence of burning or smell for that matter. I'm going to build the dim bulb tester, replace some ailing caps on the power side and reassemble the transformer with a new fuse, wish me luck!


PS- the fuse inside is a time lag ADL 4a 250v fuse, it calls for a MGC 4a 250V fuse if that has anything to do with anything. This is going to be my garage amp, it's not a candidate for a true blue restore. I can tell you all the lights are good in it and most of the dust is now gone lol.

Oh ya and one more thing to add on this turd that will hopefully work one day, the powerswitch doesn't work, off or on it always supplied 120.
 
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petehall347 said:
i have done a few now i just wire without it i know its wrong and a fire risk but only on my own equipment if i do it for anyone else i will change the thermal fuse or let them be aware .i always test the current draw to see if there might be a fault that caused it .i think they wear out i have come across lots that have gone in car battery chargers and a few in amps
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You're in the EU, right? Doing that is illegal here, even for personal use. If there's an accident and an insurance company finds out (they send out investigators), there will be trouble.
 
Wish me luck gents, new thermal fuse installed in the tranny, all new caps in the power board, 4A MGC fuse replaced the slow blow. Dim bulb tester will be built tomorrow morning and the unit will be plugged in.

newcaps.jpg
 
bktheking said:
Wish me luck gents, new thermal fuse installed in the tranny, all new caps in the power board, 4A MGC fuse replaced the slow blow. Dim bulb tester will be built tomorrow morning and the unit will be plugged in.

newcaps.jpg
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Good Luck! Looks quite a bit better, nice clean up job.

Before you power up, did you check the big Main power caps and rectifiers to be sure they're not shorted?
 
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mech986 said:
Good Luck! Looks quite a bit better, nice clean up job.

Before you power up, did you check the big Main power caps and rectifiers to be sure they're not shorted?
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I tested the recitifier, it checked out. Will test the main caps prior to launch..
 
Back to the drawing board, the fuse went again in the transformer, I suspect there is a short inside of it.
 
Did you try it with only the primary side hooked up? That would tell you if the problem was in the transformer or the receiver.

The guy I mentioned on E-bay thinks he has a transformer.

Rob
 
bktheking said:
Back to the drawing board, the fuse went again in the transformer, I suspect there is a short inside of it.
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Sorry to hear about the failure again. Time to check the transformer isolated from the rest of the power supply as mentioned. Ohm it out, primaries and secondaries and then across the two to see if there is proper values of resistance, and isolation between the windings.

Or call it a day and contact the seller who may have the replacement tranny. Discretion sometimes is the better part of valor. Besides, the copper in the tranny may be worth something to a local metals recycler. May not be a total loss. And since its only the copper that has value, you might save the endbells and laminations if you can get them out.
 
OK so here's another thought. The previous owner replaced the power cord, rather spliced the old one with a 2 prong polarized cord, could that have anything to do with it? Maybe has to do with why I have power all the time and the switch doesn't work LOL. I'm not sure who the guy on ebay is. I emailed a gent or lady off of ebay in toronto and he /she is looking for one, think so.

I'm looking on the web but can't make heads or tails of it. I never tried it isolated, I read that you aren't supposed to run them without the secondaries connected to a load. I
 
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petehall347 said:
one breaking in canada on ebay ..http://www.ebay.co.uk/itm/Marantz-2...pt=Vintage_Electronics_R2&hash=item1e60fcb06e
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That's the seller, since Sunday i've been asking, I've had time to refuse and recap the thing while waiting for a simple yes or no lol.


Thinking out loud- if this thing is wired backward and there is a short somewhere is there a possibility that it is taking out the wrong fuse? Instead of taking out the glass one it's taking out the transformer fuse? Transformer fuses are THERMAL, this thing popped the second is was plugged in. I can replace a glass fuse WAY easier then that damn thermal fuse.
 
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I have never heard that you can't run a transformer without a load.
You can.
Unless you are talking the output of a tube amp, but that's a different story.

The plug can be plugged in either way.

Rob
 
Yes I made one, tested my yamaha amp which lit the bulb up (60W) then dimmed. I hooked up the 2235, not even a flicker! Maybe it's a tube amp i'm thinking about. I checked the plug wiring, it looked good from a schematic standpoint. Ebay is littered with meggers, i'll have to think about that one.
 
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