Here is a look at C5
Cleaning up the Akai GX-630D-SS QR2R - Oh My!
- Thread starter JonUrban
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It might be easier to 'construct' a new capacitor from 4 suitable ones, but there might be a modern equivalent of the 4 cap package. I'll have a look tomorrow its midnight on this side of the pond!
Thanks Duncan. There is no rush of course, so anything you find would be helpful. I will work on documenting the wire colors and see if there are other things that need attention. Fortunately, my dining room table is in lockdown so no visitors are scheduled for quite some time, so leaving it littered with reel to reel guts is not an issue!
Let me jump in and check whether what I've been doing makes sense or if there's a real reason not to do it. Since the 1980s, I have been using a Q-Tip sprayed with Formula 409 to clean pinch rollers, followed by a dry Q-Tip to remove any residue. And for cleaning heads, capstans and metal parts of the tape path, I use denatured alcohol from the hardware store. Both seem to work well.
I did manage to get the capstan on my own original machine fairly clean, a lot cleaner than it was before, without sandpaper or any abrasives, just Q-Tips and capstan cleaner. I am not sure it's possible to get it much cleaner without an abrasive, as the Q-Tips are now showing any more brown when applied.
Before mucking with the capacitors I would spray or Deox the pitch control pot and maybe the speed change switch as well.Thanks Duncan. I actually did sign up today and download the maintenance manual from HiFi Engine! (Great minds?)
I also found that the second cap for the motors was not the black 470 micro farad cap I put in the photo, it's a larger '4 in one' cap you can see in the diagram below (C5):
View attachment 53092
It appears that the different sizes of capacitance are to compensate for either 50 or 60 Hz electrical power. I suppose I will have to get something like fan motor caps of the proper size to replace these.
Today I started tracing out the wires by color as the schematics do not indicate wire color, and they go all over the place!
So, again, thanks for the effort. I really appreciate that. I will give it a shot and see if it helps. Apparently these motors are very reliable, and from what I've gathered from Google searching the issues, the caps are generally the issue with these Akai's, along with a transistor and some diodes as a second step.
Will do. Thanks
I made a wiring diagram for the cap 'C5'. Now I will attempt to get individual caps to use in place of this 4-cap-in-a-can device!
I have found no dual 3uF+1uF, so 4 capacitors in a package. So the best bet is to make it from 3uF & 1uF 250V (minimum) rating capacitors, get some heatshrink sleeving which is handy for insulating the soldered wire to the capacitor joint.
It appears that the 1 microfarad caps are put in series with the 3's if the source voltage is 50Hz. For 60Hz only the 3's are used.
Even better as only single capacitors needed. 3uF @ 250V AC
Well, it's been a while. Thankfully, the dining room table was not needed for the summer, and today I finally got around to installing the new capacitors! Hey, I'm old, I'm slow!
Anyway, I used what they call ceiling fan capacitors and here's what they look like sitting in there. I have to figure out how to permanently mount them, but I wanted to make sure they did not explode before I screwed or glued (!) them in there.
Anyway, I used what they call ceiling fan capacitors and here's what they look like sitting in there. I have to figure out how to permanently mount them, but I wanted to make sure they did not explode before I screwed or glued (!) them in there.
And for the good news: It actually worked! The thing now does not struggle FF or Rewinding big tapes. It stops fairly quickly now and when you press PLAY it starts to play instantly. Before it would sort of ramp up to speed, like if you have the stylus on an LP and then started the platter motor.
So, I have one more big cap to replace. For some reason it got lost in the mail (can you imagine that?)
But so far, no need to call the Fire Department
So, I have one more big cap to replace. For some reason it got lost in the mail (can you imagine that?)
But so far, no need to call the Fire Department
Double sided sticky foam tape works great for items like that.Well, it's been a while. Thankfully, the dining room table was not needed for the summer, and today I finally got around to installing the new capacitors! Hey, I'm old, I'm slow!
Anyway, I used what they call ceiling fan capacitors and here's what they look like sitting in there. I have to figure out how to permanently mount them, but I wanted to make sure they did not explode before I screwed or glued (!) them in there.
View attachment 55953
That's what I was leaning toward. I really don't want to drill into the machine, and although some of them have mounting holes, the four that are together don't. But I don't want them rattling around either. So thanks for the recommendation.
Its Beautiful Jon....Great work! Its amazing how new caps make everything work so much better! I see your going through a mess of Q-tips...Did you get your capstan cleaned good?
Gotta love those big ole 10.5 inch reels!
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Its Beautiful Jon....Great work! Its amazing how new caps make everything work so much better! I see your going through a mess of Q-tips...Did you get your capstan cleaned good?
Gotta love those big ole 10.5 inch reels!
Thanks Mike,
It's pretty amazing that a little device that blocks DC and passes the effects of AC can cause a big motor to stop working well. It really made a difference!
As for the Q-Tips, I really went though a bunch of them, so I wanted to make sure I did not run out. That capstan is pretty clean now, well, at least for a 45 year old beast!
Jon,
Since your capstan is now clean.....How is your pinch roller looking? Is it hard or soft feeling and does it have any crusty marks on it?
The reason why I ask, is a machine of that vintage will surely have a hard pinch roller which increases wow and flutter even with a clean capstan. I have over the years have had my pinch rollers rebuilt from 1/4" machines to my 2" machine twice. I use this guy named Terry:
http://www.terrysrubberrollers.com/
He is very reasonable price wise...may take a few weeks to get it done...but you have done so much to refurbish that beautiful machine you may want to go ahead and redo the roller as well...It will pay big audio dividends in the long run and make your tapes sound better because the tape is tracking the heads better.
Just a thought
Since your capstan is now clean.....How is your pinch roller looking? Is it hard or soft feeling and does it have any crusty marks on it?
The reason why I ask, is a machine of that vintage will surely have a hard pinch roller which increases wow and flutter even with a clean capstan. I have over the years have had my pinch rollers rebuilt from 1/4" machines to my 2" machine twice. I use this guy named Terry:
http://www.terrysrubberrollers.com/
He is very reasonable price wise...may take a few weeks to get it done...but you have done so much to refurbish that beautiful machine you may want to go ahead and redo the roller as well...It will pay big audio dividends in the long run and make your tapes sound better because the tape is tracking the heads better.
Just a thought
Jon,
Since your capstan is now clean.....How is your pinch roller looking? Is it hard or soft feeling and does it have any crusty marks on it?
The reason why I ask, is a machine of that vintage will surely have a hard pinch roller which increases wow and flutter even with a clean capstan. I have over the years have had my pinch rollers rebuilt from 1/4" machines to my 2" machine twice. I use this guy named Terry:
http://www.terrysrubberrollers.com/
He is very reasonable price wise...may take a few weeks to get it done...but you have done so much to refurbish that beautiful machine you may want to go ahead and redo the roller as well...It will pay big audio dividends in the long run and make your tapes sound better because the tape is tracking the heads better.
Just a thought
Mike,
I don't think it's too bad, but I would not be adverse to getting it redone. I wonder how difficult it is to take off? I'll look into it and if I can get it off I might just send it off, if Terry is accepting new wheels these days.
The silver cap unscrews lefty loosey and the roller should lift off.
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