Hello, this is my first post on diyAudio, but very likely not my last.
Does this look like a solid kit for a McIntosh MA-5100? Overpriced?
McIntosh MA5100 FULL restoration recap repair service rebuild kit capacitor | eBay
Also, I have some experience recapping crossovers and doing some other through-hole soldering. I feel confident doing both, but I'm wondering if this might be over my head. What's the skill level involved for something like this?
Thanks so much, I'm excited to get started in this community/hobby
--JBaeckel
Does this look like a solid kit for a McIntosh MA-5100? Overpriced?
McIntosh MA5100 FULL restoration recap repair service rebuild kit capacitor | eBay
Also, I have some experience recapping crossovers and doing some other through-hole soldering. I feel confident doing both, but I'm wondering if this might be over my head. What's the skill level involved for something like this?
Thanks so much, I'm excited to get started in this community/hobby
--JBaeckel
Overpriced, yes!
But you do get to bug him for advice -- like here!
Here's an excellent photo of underside of MA-5100:
McIntosh MA 5100 | McIntosh MA 5100 | Willi Vintage | Flickr
But you do get to bug him for advice -- like here!
Here's an excellent photo of underside of MA-5100:
McIntosh MA 5100 | McIntosh MA 5100 | Willi Vintage | Flickr
Thanks, that seems like it might be invaluable for a newb like myself!! I ordered the Amp Camp Amp to get myself on a little more solid footing. Perhaps after that I will fee more confident attacking the MA-5100.
There are a bunch of film caps in that kit.
Unless he has supplied .47 to 10 uf film caps to replace .47-10 uf electrolytics, that is unnecessary IMHO. Film caps rarely go bad. I've got cheap consumer radios & tape decks full of .47-10 uf electrolytic caps but I would not find that likely in a MacIntosh. Electrolytics have a plus near one lead or a minus in balls near the other.
The kit does show nichicon logos on the electrolytics, which is a good idea. I would hope those are the long life grades, with better sealant, but you can't tell without the full part number on the bag the cap came from the distributor in.
Be sure to mark the board with + near the plus lead before you pull the old caps. Backwards electrolytic caps explode on power up. Wear safety glasses desoldering, solder splashes. I like a sucker bulb to remove solder myself, got mine at parts-express.com
Unless he has supplied .47 to 10 uf film caps to replace .47-10 uf electrolytics, that is unnecessary IMHO. Film caps rarely go bad. I've got cheap consumer radios & tape decks full of .47-10 uf electrolytic caps but I would not find that likely in a MacIntosh. Electrolytics have a plus near one lead or a minus in balls near the other.
The kit does show nichicon logos on the electrolytics, which is a good idea. I would hope those are the long life grades, with better sealant, but you can't tell without the full part number on the bag the cap came from the distributor in.
Be sure to mark the board with + near the plus lead before you pull the old caps. Backwards electrolytic caps explode on power up. Wear safety glasses desoldering, solder splashes. I like a sucker bulb to remove solder myself, got mine at parts-express.com
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Thanks indianajo! Very helpful information.
There are definitely more film caps than electrolytics. I count 19 electrolytic in the service manual including the power supply cans and some labeled "Ta. Elect." (any idea what that means?) and 26 Mylar. What can I look for in the part numbers to know if the electrolytics are the long life grade? I would hope they are at this price point!
I'm probably going to regret it, but I'm replacing all the film caps while I have it apart (replacing caps is the easy part, getting access to the boards is the real pain). Some of the film caps are polypropylene and some are polyester, there doesn't seem to be a rhyme or reason to where each are used (the seller sent polypropylene caps to replace some of the polyester he forgot to send in the first shipment and said they're all the same). The biggest disappointment was the large reservoir caps would not fit without cutting my amp cabinet.
So far so good on the recap though, It's way easier than I thought it would be. One of the caps had a positive lead that was different on the physical board than shown in the schematic, I went with what was on the board. The biggest pain is soldering the wires that connect the board to the other amplifier components. They have these little pins on the ends of the wire that are difficult to get back into the original holes.
The seller also sent a bunch of bridge rectifier diodes for replacement, are those actually worth replacing?
Hopefully nothing explodes when I power this sucker back up! I'm planning to test the amp after recapping each component.
There are definitely more film caps than electrolytics. I count 19 electrolytic in the service manual including the power supply cans and some labeled "Ta. Elect." (any idea what that means?) and 26 Mylar. What can I look for in the part numbers to know if the electrolytics are the long life grade? I would hope they are at this price point!
I'm probably going to regret it, but I'm replacing all the film caps while I have it apart (replacing caps is the easy part, getting access to the boards is the real pain). Some of the film caps are polypropylene and some are polyester, there doesn't seem to be a rhyme or reason to where each are used (the seller sent polypropylene caps to replace some of the polyester he forgot to send in the first shipment and said they're all the same). The biggest disappointment was the large reservoir caps would not fit without cutting my amp cabinet.
So far so good on the recap though, It's way easier than I thought it would be. One of the caps had a positive lead that was different on the physical board than shown in the schematic, I went with what was on the board. The biggest pain is soldering the wires that connect the board to the other amplifier components. They have these little pins on the ends of the wire that are difficult to get back into the original holes.
The seller also sent a bunch of bridge rectifier diodes for replacement, are those actually worth replacing?
Hopefully nothing explodes when I power this sucker back up! I'm planning to test the amp after recapping each component.
Tantalum Electrolytic.
Tants were very fashionable many decades back. At the time they were smaller and less leaky than Aluminum (ordinary) electrolytics. Some said they sounded different (but they shouldn't). Passion has cooled since old Tants tend to blow-up violently, and Al electros have improved SO much since those days. Today I would choose a "LL" (low leakage) Al rather than a Tant.
Thanks PRR! I still don't understand how those are shown in the parts list. It seems like they are repeats of already named capacitors. I'll attach some screenshots as an example.
In order to make rewiring the board to all the other components less of a pain, is there anywhere to buy single pin through-hole screw termination blocks? I searched on mouser/digi-key/adafruit and the smallest I can find is 2-pin.
In order to make rewiring the board to all the other components less of a pain, is there anywhere to buy single pin through-hole screw termination blocks? I searched on mouser/digi-key/adafruit and the smallest I can find is 2-pin.
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It looks like the typesetter has trouble with spacing within numbers.
A single-pin screw block would tear itself off the PCB pad when screwed.
A single-pin screw block would tear itself off the PCB pad when screwed.
Hello,
Does anyone know the specifications of the thermal cut out S302 and S303 (part number 153-007)?
I ask because I recently bought a unit to restore that is 117V and in Europe we have 230V so to test it I had to use a step down transfomer but it comes out of the speakers a sound very similar to a transformer and I don't know if this can be because of the step down transformer or the amplifier transformer. I have seen the schematic and I see that I could connect the primaries of the transformer in series but I don't know the specifications of the thermal cut out. The only information on them is the following and I can't find anything on the internet: Elmwood Sensors L180 87-5
Thanks in advance,
Greetings
Does anyone know the specifications of the thermal cut out S302 and S303 (part number 153-007)?
I ask because I recently bought a unit to restore that is 117V and in Europe we have 230V so to test it I had to use a step down transfomer but it comes out of the speakers a sound very similar to a transformer and I don't know if this can be because of the step down transformer or the amplifier transformer. I have seen the schematic and I see that I could connect the primaries of the transformer in series but I don't know the specifications of the thermal cut out. The only information on them is the following and I can't find anything on the internet: Elmwood Sensors L180 87-5
Thanks in advance,
Greetings
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