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DIY Recapping/Restoration

82smithtown

82smithtown

270 db = Perfect
Good morning and Happy New Year!

I have two main stereo systems in my house. The large one in the living room consists of EV S15-3’s that are mint with rebuilt x-overs, and the smaller bedroom system has JBL 4406’s.

I just recently purchased a never-used-in-box Hitachi HA-2 amplifier to push the JBL’s for $63 on eBay. Very excited as that model goes way back in my life and brings nostalgia. Haven’t gotten it yet ....

That buy comes while I’ve also been searching around to restore the living room source equipment. I want to do a recap and service, but am unsure if I should try this for the first time on gear I love and want perfect infinitely. I’m a well credentialed Stationary Engineer, but rarely in that trade do you get practice working on small, delicate boards.

The best local shop wants a $140/unit deposit before even telling me what else is needed, which is hard to rationalize. I’m wanting to service all of my equipment.

Thoughts?? Should I try DIY or bite the cash bullet?

Equipment in question:

CD Player - Kyocera DA-410CX
Receiver - JVC R-S33
New Amplifier - Hitachi HA-2

Cheers!
 
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If I were you, I would first practice on something that I did not care about. It is easy to ruin solder traces or short them. It takes some experience and skill to properly recap and troubleshoot any electronics.
 
+1 to the above. Soldering / recapping is not terribly difficult but there is a right and wrong way to do it. I learned by practicing on some old dead NES games that I had. Watch online videos showing the correct way to do it too, that will be a big help. As for the actual troubleshooting part, that's definitely more complicated. Depending on how deep you want to dive, the equipment could get fairly expensive too. At the very least, you'll want want a decent multilmeter and a dim bulb tester is recommended as well. From there, you could be looking at signal generators, oscilloscopes, etc. The members here are very helpful too so depending on what is actually wrong, they can very likely guide you through the process with minimal equipment.
 
+1 on the above......Practice, practice, practice.

There is plenty of cheap stuff at Goodwill or similar thrift's that you can use to get comfortable with.

If you are like me you will find unsoldering is more challenging than soldering. Getting the old solder off without damaging the traces can be a trial in patience.

OTOH, unless your current equipment is not performing correctly there may be little benefit to recapping especially considering the risk of damaging the gear if something goes wrong. Your paid tech has just as much a chance to screw things up as you do, it may be better to leave well enough alone. If it ain't broke.......
 
Thanks for the replies!

As mentioned, I do Stationary Engineering in high rises, and do own a soldering iron, solder suckers, electrical tools and a few multimeters (one being Cat III, 1000v and over $400.... ;)

Having the tools for the job is not my worry, more just the fact that we work with large machinery, not tiny boards.

What would be the main part to worry about when recapping an amp? Solder floating to other contacts?
 
lowercasee said:
+1 to the above. Soldering / recapping is not terribly difficult but there is a right and wrong way to do it. I learned by practicing on some old dead NES games that I had. Watch online videos showing the correct way to do it too, that will be a big help. As for the actual troubleshooting part, that's definitely more complicated. Depending on how deep you want to dive, the equipment could get fairly expensive too. At the very least, you'll want want a decent multilmeter and a dim bulb tester is recommended as well. From there, you could be looking at signal generators, oscilloscopes, etc. The members here are very helpful too so depending on what is actually wrong, they can very likely guide you through the process with minimal equipment.
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Yup. I’m a beginner with soldering, and am yet to perform my first recap, however I have had to solder when replacing speaker drivers.
I practiced with my iron on an old plasticky portable cassette player... a cheapo one from when walkmans and such were dying out.
 
The main things are getting the polarity, voltage and value of the new capacitor correct. Also that there is good solder flow creating a good solder connection. I'm sure you could find some youtube videos on this. Also, for larger caps with higher voltages, you need to make sure the cap is discharged. You can use a volt meter to check and a 100 ohm resistor to discharge. This is assuming your working on solid state, tube equipment tends to work with much higher voltages and can seriously hurt or kill you. A dim bulb tester is a must to protect against shorts while working on the amp

The first amp I recapped, I replaced one cap and then tested the amp. I did this for every cap because I was unsure about the process and I didn't trust my skills. After I gain some confidence I was able to replace more at one time. If you make a mistake, you'll need to go back and check your work. This is easier when fewer caps are replaced at one time.
 
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Come to think of it, the Sony amp that the Hitachi I purchased will replace wouldn’t break my heart if it were to become a sacrificial unit......I may wait till the Hitachi is in place and break open that Sony to service. Best case, it comes out happy.

Now come more questions....

- Wouldn’t all this early-80’s equipment be in desperate need of servicing? (albeit they still sound great to me...)
- What caps etc. should be replaced when I do break them open? What on the CD player?
- If this Hitachi was truly unused/open box, would the caps be perfect having never been stressed or dried out internally from age?
- Should electrolytics be swapped for poly caps?
- Should I get higher voltage (NOT higher uF) caps to keep heat down and prolong cap life?
- What would be viewed as low cost or high cost when it comes to having a unit commercially serviced?

Thank you all -
 
I picked up a Marantz 2238B on the cheap with a bad relay and recapped that thing and cleaned up the relay to get it working. It was good experience for doing my 2252, which I actually care about. No issues, but it's not the most professional job. The 2252 looked a lot better.
 
- Wouldn’t all this early-80’s equipment be in desperate need of servicing? (albeit they still sound great to me...)
Not necessarily. This is an area of varied opinions and great debate even here. There are many compelling arguments on both sides of the debate. There are issues with some components, namely Tantalum capacitors and some transistor types which are known failure points but not every piece of gear has them. Researching individual units here on AK will usually lead to a thread discussing known issues with a particular piece of gear.

- What caps etc. should be replaced when I do break them open? What on the CD player?
Typically the power supply is the first area to get attention. The belief being these are some of the most "stressed" components due to the heat and voltages they encounter. Next would usually be the amplifier section. There are two "sections" in the amplifier; the power side and the signal side, usually different capacitors are used in each side. After that the Phono pre amp and tone control sections would complete the re-capping. Very rarely are the tuner sections restored/serviced as specialized equipment required to align the tuner after any parts are changed. In the CD player the power supply and output stage could potentially benefit from some attention.

- If this Hitachi was truly unused/open box, would the caps be perfect having never been stressed or dried out internally from age?
See answer to question 1. Electrolytic capacitors are similar to a swiss roll, a sheet of foil is covered with a sheet of paper and rolled up. The thickness of the foil and paper along with the length and number of rolls determine the capacitance. A 1uf capacitor has more paper/foil than a .1uf capacitor.
You will probably notice a change in the sonic signature after several hours of use due to the internal components like capacitors "charge/discharge" and transistors and resistors heat cycle a few times.

- Should electrolytics be swapped for poly caps?
Not typically inside of electronics but very commonly in speakers.

- Should I get higher voltage (NOT higher uF) caps to keep heat down and prolong cap life?
Higher voltage caps wont reduce heat. They will possibly live longer as the engineers spec the minimally acceptable components for production. You could also potentially improve the lifespan of the unit by using caps with a higher temperature rating. Replacing a 50v 85c capacitor with a 63v 100c capacitor is common as long as the capacitance remains the same.

- What would be viewed as low cost or high cost when it comes to having a unit commercially serviced?
That really depends on the level of "service" and area you live in. Understand that restoring and servicing are very ambiguous terms. There are many other components that can deteriorate with time and usage. there are transistors that are known to become noisy and failure prone, resistors can also drift with age and exposure to heat. How many of these components will get tested and/or replaced during your servicing/restoration will have an impact on the cost.

Keep in mind that very few components available today are EXACT replacements for originals. While most are very close, small variations can make a difference. When you add a bunch of small variations together(tolerance stacking) you could end up with a unit that no longer performs as the designer/engineer originally intended. It may be better.......then again it may not.
 
The Kyocera would probably be the easiest to work on once you feel comfortable soldering. Just focus on replacing electrolytics with like capacitance using the same or higher voltage than the originals; a schematic or dim bulb tester are not necessary to recap electrolytics. While not a necessity, I found using Cardas Quad eutectic solder makes soldering easier (in general) because it flows/ hardens instantly and reduces dwell time and potential damage in addition to using a higher wattage soldering iron on high heat allows you to get in and out quicker, causing less (potential) heat damage to components.

I would replace any electrolytics 1uf (or less) with better cap materials, such as the polyester you mentioned, or better yet, polycarbonate or polypropylene. Polystyrene is a top choice, but not recommended unless you have lots of hours with the soldering iron as they are easily heat damaged unless you heatsink the leads with a metal alligator clip while soldering each leg in. I have performed several dozen recaps, and as long as you replace part for part carefully observing correct polarity it's hard to mess up unless you are using too much dwell time or have difficulty de-soldering old caps.

I would recommend purchasing both de-soldering wick as well as a solder vacuum sucker so that you have the option of using both if one isn't working to remove that last, stubborn bit of solder. You can almost always avoid tearing pcb traces if you melt some fresh solder to problem joints before de-soldering them. Also, never force a cap out with physical force if you have already removed the solder and it still isn't moving. It will tear the trace.

Not too worry, if you do tear a trace it can be easily repaired by scraping off the green pcb coating to expose some surrounding fresh copper and soldering directly to it (preferred) or by using a Circuit Writer silver pen to restore the original torn trace. I have used this pen on several occassions and it always works. I recommend using the Elna Silmic audio caps in all locations, except for the larger power caps because they aren't available in high capacitance.
 
wmgwizard said:
Very rarely are the tuner sections restored/serviced as specialized equipment required to align the tuner after any parts are changed.
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Replacing electrolytic capacitors in a tuner should not affect alignment. No engineer / designer would use an electrolytic cap in a circuit that is critical for alignment. Now start replacing any other caps and all bets are off.
 
redk9258 said:
Replacing electrolytic capacitors in a tuner should not affect alignment. No engineer / designer would use an electrolytic cap in a circuit that is critical for alignment. Now start replacing any other caps and all bets are off.
Click to expand...

As the OP is a novice I would not recommend he try and determine which caps in the tuner section are critical for alignment and which ones are not.
 
Good advise from all above. Also know that you can't always trust polarity markings on the boards. I always put the new caps in in exactly the same orientation as the original.
 
wmgwizard said:
As the OP is a novice I would not recommend he try and determine which caps in the tuner section are critical for alignment and which ones are not.
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Electrolytics won't affect alignment. They're too variable by nature and normally aren't used in that curcuit. However they can affect overall tuner performance and sound. But if any of the low value light blue SANYO caps are found, they should come out immediately and be replaced by film (or electrolytic). However there probably won't be any in late 1980's equipment.
 
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