Small job on AU999, BIG job on AU-X1

That would be a loss not to have ya' brother!

Well, actually I have to do a bit of work to my C33 and 2205, I was thinking of starting a thread, so it might not be over just yet, we'll see how it goes once I get started...
 
Everything is holding well, stable, so I put the front on and the bottom on, I'll run it for a few days and then recheck everything.
Its on the test bench now running the turntable.....really nice clean and detailed sounding Phono pre, pity I don't have a MC cart to try out, but none the less, the VMS20 is great, we are getting a nice fat sound!!

I'm also waiting for the lamps to turn up, so this is as far as assembly goes right now, they should be here courtesy of Dave the resident lamp guy next week.

Really all in all, apart from a couple of "I know better than you" and "gottcha" moments and wild goose chases with a couple of rather odd issues, this amp has seen little work, I think its very low miles....
But I suspect there were a few issues that came up which had it destined for storage and then forgotten about....
I also think its a late model, lots of grounding amendments by the looks...

It is a JDM model so 100V, I will have to see what the owner wants to do, plenty of 2:1 transformers around that give us 115V down here in NZ, but really, that is too high, I'm running it through my Variac into a 115V step down, I have it set to 100V exactly.....nothing gets warm, even when I had it really cranking for about a half an hour...
Really impressive, but I would say it would be a different story running it all the time on 115V 15% overvoltage...

Few pics....
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Nice work there. Mine runs almost every day and it beats all other stuff I have. But I still have to compare it to my Yamaha B1 when that finally returns. Just like Hyperion I have to find time to finish it completely. I still have to put the restored phono boards in, but that means I have to unplug it .
However it should get warm especially the phono boards which run in Class A. Did you already test the stability of the amp?
 
Nice work there. Mine runs almost every day and it beats all other stuff I have. But I still have to compare it to my Yamaha B1 when that finally returns. Just like Hyperion I have to find time to finish it completely. I still have to put the restored phono boards in, but that means I have to unplug it .
However it should get warm especially the phono boards which run in Class A. Did you already test the stability of the amp?

Well, after reading your restoration thread, mine is fairly lightweight compared to what you did......However, the unit it functioning well and I am very happy with the way it turned out.
I was about to do some stability testing when I discovered the square wave function has stopped working on my generator.
As soon as I have this resolved I will do some testing.
 
I noticed a Hitachi epoxy covered reed relay back several posts. I presume it's a headphone relay in this unit.

IME, they are proving to be unreliable little buggers as time marches on. The green epoxy coating stuff eats into the copper windings around the two encased glass reeds. Much mid to late 80s Japanese gear had them inside. Just a heads up. :)
 
I noticed a Hitachi epoxy covered reed relay back several posts. I presume it's a headphone relay in this unit.

IME, they are proving to be unreliable little buggers as time marches on. The green epoxy coating stuff eats into the copper windings around the two encased glass reeds. Much mid to late 80s Japanese gear had them inside. Just a heads up. :)
What would be a good replacement for those green reed relays?
 
What would be a good replacement for those green reed relays?

I've wound my own a few times (taped two reeds together and spun the pair in a drill chuck while winding copper wire from a 'donor' relay). You need a working one to measure first for resistance before you start however.

You can get SPST 12v reed relays for cheap and run two in series to give you a 24v DPST relay. Often, those green blob relays are used where extremely low level signals are (in MC/MM switching etc) being switched and normal relays either have to much contact resistance, deteriorate, or add crosstalk.

If the little buggers are just headphone relays, you can use pretty much anything and get away with it.

IIRC, the L24 means it is a 24v relay- I'm not sure how many other voltages Hitachi made in those nasty little things. Lots of Hitachi cassette decks used them as tape monitor relays and Akai used them inside preamps/cassette decks etc. Marantz used them as headphone relays in the better gear in the 80s.
 
What would be a good replacement for those green reed relays?

Personally I would use one of the Omron G5V replacement types already used on the Phono mother board, you'd have to wire them up the same, and they wouldn't look great, but it would work. I have never seen replacement relays with the same package as the original green ones, but that doesn't mean they don't exist. :) (NB: also used in the AU-919 and probably others).
 
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It is the headphone relay, just looked it up, yeah might not be a bad idea to replace that.
You could pretty much use anything that will fit.
I have a couple of little issues to attend to on the mother board that the Phono board plug into, I have to remove it, I think there is a cold solder joint or a crack in a track somewhere as we are having a few intermittent issues that relate to that board....
Might as well see what I can do for a relay for the headphones while I am at it....
 
...I have never seen replacement relays with the same package as the original green ones, but that doesn't mean they don't exist. :) (NB: also used in the AU-919 and probably others).
Check US Relay manufacturer Struthers-Dunn: RR2A-24VDC, MRR, RR Series - Axial Lead, Shielded Reed Relays
Providing the spec's are able to emulate some of the Hitachi L24's quality's - this could be a possible(?) replacement - providing you are able to source them!

Edit:
Link to datasheet: RR/MRR Series
 
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So in the middle of finishing up this job, I moved my Lab, so then once that was set up I could carry on with the X1.
So I fired it up, and one channel had dropped out, and the protection circuit was playing up and acting the fool.
It turned out to be just a couple of dry solder joints, but they evaded me for a while, and not before I had taken the back off to check speaker relay operation....took the front off again to access the board with the speaker selection switch on, then discovered the power switch had a faulty element.....
I was chasing this nonsense around for a good 6 hours.....
Anyway. I started the amp up this morning and ran it all day streaming a good radio station and it ran faultlessly, at times I had it cranked right up....
So a couple of hours ago, I decided to put its pants on.....Its scrubbed up quite well...I am very pleased with it...

Damn thing sounds insane!! I love it!!
A few pics of the X1 tidy up in the new Lab.....I have some more test gear on the way, I am starting Tuner alignments, so I have a multiplex generator, sweep generator with markers arriving any time now, already got the RF generator...yes I am entering the voodoo world of tuners, I've always had an interest in tuners and I have extended my knowledge and I am going to put it to good use....
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There you go ;) a piece of cake for someone with your experience. It looks beautiful, nice and clean Kev, "scrubbed up well" :thumbsup:

I am pleased you think so well of how it sounds, your opinion means a lot, mine adds a depth to the music like nothing else I have.

And tuner alignment! - now you have yourself a tiger by the tail :D - but I am sure you will master it. :king:
 
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