Roksan xerxes

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Ant
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#31 Re: Roksan xerxes

Post by Ant »

More work required on the psu
Switched on this morning and was greeted by an awful vibratory noise and little rotary motion. Taking the platter off, the obnoxious noise was actually the belt flapping around like dtbs trousers anticipating a hadouk trio gig. The motor appears to have being undecided wether to go forward or backward

Switching it on and off a couple of times miraculously cleared the fault. Its running as its supposed to right this minute.

Could be related to the caps i didnt replace, that will be the first port of call. They were small value electrolytics i didnt have in the spares box. The ones i took out were rated at 85 degrees, i wouldnt hazard a guess as to how close to that the temps inside the box were before hacking holes in it but it was hotter than a hot thing

It wont beat me

Onwards! (To the internet with bank card in hand)
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Daniel Quinn
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#32 Re: Roksan xerxes

Post by Daniel Quinn »

Ant I completely forgot about the tone arm bits I was sending you . I’ve had a major brain bleed don’t you know 😉

Remind me in future. I was looking for something I there were in my tool box remind me . Do you still want them if so it will be on its way today?
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Nick
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#33 Re: Roksan xerxes

Post by Nick »

I may have misread but have you completely removed the suspension from the deck?
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Ant
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#34 Re: Roksan xerxes

Post by Ant »

Yes please DQ, I'd like to give them a go and see wether there is any difference between them

Nick, no I haven't removed the suspension from the deck, I've just pinned the cutout with 2 rods to remove the top plate sag
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Nick
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#35 Re: Roksan xerxes

Post by Nick »

Ok, it just looked to me that you had connected the bit that moves to the bit that doesn't move, but I don't know the deck so my mistake.
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Ant
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#36 Re: Roksan xerxes

Post by Ant »

the top sits on 3 mounts to decouple it from the base which the motor is attached to, the top plate has the notorious sagging cutout which is there to alter the resonance of the top plate. the bearing and arm sit on the bit that sags down so the alignment between the arm and bearing goes cockeyed when it does inevitably sag down, and the belt will slip off as the bearing goes out of alignment with the motor
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Daniel Quinn
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#37 Re: Roksan xerxes

Post by Daniel Quinn »

Ant there on the way .
Ant
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#38 Re: Roksan xerxes

Post by Ant »

Cool. Thanks dq
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#39 Re: Roksan xerxes

Post by Ant »

Curiouser and curiouser.
Ive been given a supposed 110v version of the roksan xps7 power supply for the deck, and taking the top cover off to see wether the expected toroid primary can be reconfigured to run on 240v, i find a pair of drop in transformers that are marked as 230v primaries..... one is 15-0+15-0 sec and the other 12-0+12-0 sec.
The serial numbers also conform to the 230v primary version of said transformers.
The pcb is also marked as 230v, and was manufactured by heed audio and dated 08/03/05.
I find it very hard to believe that it is a 110v model.

Is there a way to test the transformers to see what the primary is?

I suppose i could remove one and put the stated vac on one of the secondaries and see what comes out of the primary?
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Nick
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#40 Re: Roksan xerxes

Post by Nick »

I suppose i could remove one and put the stated vac on one of the secondaries and see what comes out of the primary?
That would be my way of testing them. Though I would start with maybe 50AC on the primary and work out the ratio from that.

What supply did the 230v one you have use? They may have just used them as 7.5+7.5v and 6+6v transformers.
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#41 Re: Roksan xerxes

Post by Ant »

The original psu that i have is the first gen class a job from 1985 so is a completely different design. Roksan binned that psu off pretty sharpish because it was unreliable.
If i had a variac i could have stuck a lower voltage on the primary, i dont have anything that i can use to put a reasonably large voltage on the primary but have got a couple of wall wart ac transformers that are 9 and 12v which is why i though about testing off the secondary instead.

Ill have to test both txs, it wouldnt do to blow it up by pluggi g it straight in despite what the serial numbers and primaries say
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Nick
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#42 Re: Roksan xerxes

Post by Nick »

Just try the 12v on the primary. The ratio will be the same.
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Ant
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#43 Re: Roksan xerxes

Post by Ant »

Got hold of john who sent me the psu, turns out he has sent the wrong one!
Thats cleared that up
I now know the serial numbers for the uk spec transformers though so if i can get some for the correct 110v one it can be converted. Depends wether its cheaper to get a step down and a us iec lead for it
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Ant
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#44 Re: Roksan xerxes

Post by Ant »

Got the 110v psu off john today, i put the xerxes back together (put it away and took the arm and cart off it to make space for the jvc y3) on wednesday morning as pete from another forum came round and wanted to hear it. The original psu was still playing up. But some swearing got it running.

Ill have to get hold of a 110v transformer and an american plug iec lead rather than swapping the transformers out as the correct ones are unobtanium at the moment and im abit leery of trying to bodge some different ones in

I do like how this deck sounds. Might fetch it to owston
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Bill-e-boy
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#45 Re: Roksan xerxes

Post by Bill-e-boy »

Hi Ant
The old psu you have pictured is indeed a first gen power supply. XPS1
The main issue as I see it is that the heat from the current dumping resistors just heated every thing up too much and I think a lot of the skinny PCB tracked suffered as well = I am sure that a lot of problems were caused by heat induced cracking on the PCB tracks and this also caused component failure
I swapped my XPS1 for an XPS2 to early on so that my XPS1 became a spare - went us it last week - oh dear here we go again
I have had my original Xerxes since 1988 and now have three of these in various configurations
Main deck - Xerxes, XPS8 (this is good), Artemis and Benz Micro Wood
Second Deck - Xerxes, XPS2, Tabriz (with fixed weight), Benz Micro
Third Deck - being worked on - Xerxes, no psu, RB300 (original with small weight), cart tbc
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