Want to put together a recapping guide

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JDMiller1988

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Ok, so you all really inspired me. I was able to recap my sony tc-777s thanks to the kind folks on the board. If I can do it anyone can, (really).

I would like to put together a how to recapping/basic refurb (nod to the recent slider restore thread) guide. I am not really the one to do it but I can say what helped me.

Some basic info on how to go about reading schematics and tracking down new caps. i.e. how to figure out what the marking on caps are, decent soldering techniques and basic tools.

Anyone think this is a good idea? I just want to consolidate some of the info on the forum into a more how to guide that can maybe be pinned here in the analog only section. I mean why not right, recapping 40-60 year old decks is definitely a must if you plan on using it right?
 
I have not posted in this forum in a long time. English skill set shy i guess.
I came out of the treanches to tell you this is a great idea!
Please help us. And thanks for taking the time to give back.
 
I agree it is a good idea. You might get it sticky'ed, or more, if it's really good.

I'd suggest you get another machine that you can get the schematic for, and take and post in-progress pics along with the narrative. Each machine will be different, but most can extrapolate to a different machine.
 
Slightly off topic, but on GroupDIY, they have a sticky meta. If you want, e.g. the help thread on the Green Preamp you can go to the sticky meta and look under "Project Specific" and drill down to Green Pre, that will take you to a page with links to threads on the green pre.. Also, and equally important (MODERATORS LISTEN UP!) you can edit a post indefinitely, so the meta basically becomes a link to other threads that can be updated, but remains itself a short post with a lot of updated links.

Additionally, that would be a good place to put e.g. the DX-4D mod, DrZee's R8 repair guide, and some of the various repair threads, (perhaps my ARP Quadra computer thread, Cory's Ampex threads etc.)
 
That would be great. I'm about to start diving in to the world of refurbishing electronics and is interested in anything that can push me over the threshold and get me started.
 
Excellent idea. We all will undoubtedly have to recap at some point.
 
No need to recap unless there are caps that show signs of discharge, expanding or are broken, electrolytic caps are usually the main culprits & resistors that have drifted our of spec. These often make crackling noises. You might find an improvement in sound, dynamics & clarity if you upgrade caps, easy to do one channel card at a time on a reel to reel recorder & compare to the stock channels.

Usually the power supply filter caps would need replacing after 15-20 years or so, you'll know when there is electrical hum, these are the biggest electrolytic caps inside & rated at the highest voltage so be careful of voltages around this area.

Pull out a channel card on your machine, look at the different types of caps, electrolytic caps have one lead longer than the over, one positive, one negative so any replacements have to go back in the right way around or they might explode & mess up time & space or similar!!!

Here's a picture of a Tascam TSR8 channel card attached.


Bottom right on it's side is a axial electrolytic cap, probably around 35V -63V (Voltage) with the value in uF also written on the side, replace with the same voltage value or higher, there's probably around 20 on this PCB board & some extra yellow types.. The back of the board will have a + sign for the positive pin beside the solder holes for that part. The cap will usually have a strip down the side for polarity. +/-

The red & blue caps are normal polyester, mylar or similar caps, it doesn't matter which way these are inserted just replace with same or higher voltage value. There will be cap codes on these to denote cap value ie 104 Just do a search for a cap code chart to find out the exact values. Also watch out for those mustard / yellow caps around the same size, they might well be Tantalum caps which like electrolytics would to be installed with the proper polarity !!!

The resistors, mostly cream coloured on this PCB have stripes across to denote ohms value & resistance, usually they are 1/4 or 1/2 watt with an odd 1 or 2 watts, check all these with a magnifing glass to see if they are breaking apart or expanding, these look like carbon films & a couple of these types were faulty on my TSRS causing crackling on one channel board. Look for a resistor value chart or there are java programs for your computer to download & install.

Most of the rest including opamps, relays, transistors, pots, connectors & inductors won't need replacing unless faulty.

Best way to start soldering if you haven't tried it before is to make / or mod a Guitar FX pedal, plenty of kits out there including BYOC!!!!
 

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Electrolytic caps degrade quickly and especially those from the 70's & 80's. Don't buy a statement no need to replace!

Caps have undergone great development change in past 5-10 years, and it is worth every effort to replace them all especially in the power supply if one intends to keep the equipment.

Making a guide is a tough job but somewhat doable. It's matter of experience and understanding what should be replaced and how best to dot hat to avoid an circuit board damage.

If one has little experience soldering then experiment on something other than a good circuit board until one has the "feel".

There are plenty here who can lend experience.
 
Are the E16 audio cards really made by TEAC...?

EDIT: That looks a heck of a lot like a TSR-8 card, actually.
 
Lol! It was late at night, anyway the Fostex has yellow cards as well, must have the photos mixed up!!!

I was making a point saying replace anything that is faulty first before just replacing caps for the sake of it. It can work out very expensive for very little perceived benefit. Many on the Prodigy DIY forum would say the same. I've used Panasonic & Nichicon electrolytic caps in Neve clone preamps & other compressor builds, but don't know if upgrading the electros or even Poly caps on a Tascam / Fostex channel card would make a difference.

Which exact caps are most important in the signal chain in this instance & also maybe the opamps could be upgraded to Burr Browns or anything better?

I've been looking out for a spare TSR8 channel card to experiment on as I have some electros & opamps including Burr Browns in my spares stash!!!!
 
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