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Old TO-R s15u, Should i fix it?

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This is one old beast, i cannot find much about it and my experinces with tubes are kind of limited. might this be any good? exterior is really good but the inside is worse, this will take some time to recondition. so my question is: do you guys think it is worth the effort?

TO-R s15u with tubes: ECC85, EF89, EF80, EM87, ECC83, ECLL800

Note, the black caps point soldered to the vol. pot are cracked... i have no idea why, as said... this one will eat time.
 

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Final stage using ECLL800 looks interesting, a triode as PI and two pentodes in one bottle.

If the outside looks nice, and the transformers are ok, I would probably try to refurbish it. Check availability of the tubes, though.

Regards,
Andreas

EDIT: Had those black caps in a lot of old tube radios, they're potted in some kind of tar and get leaky (in an electrical sense) with time, usually leading to their destruction, sometimes amongst other, innocent components. Change them all.
 
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Thanks for your answer, this brings a little hope to it. I will tear out the transformers, test them out and take it from there then. caps are prone to fail with time (we all know) but it sounds good that this ones are extra "bad", after a closer look at it every black cap looks cracked.

//J
 
If it is the first restoration project, keep in mind some safety issues:

* the unit seems to be connected to the mains without earthing, if there are any metal parts on the outside, there should be a safety ground connection

* there is a cap in the power supply part (C805?) which is directly connected between the mains and the power supply ground. Given the age of the unit, I wouldn't trust that cap - if it's leaky/shorted, it defeats the mains isolation provided by the power transformer.

Andreas
 
.... but the guys from the Netherlands seem to have used them as well...

Andreas

This time the guys from the Netherlands are Danish, built in 1961 :D

In any case those black cap's need to go. 25 years ago I replaced them on sight and I don't think they've improved since :)

Other than that I remember the tuner being fair to good but of course stereo only comes from the attached AF-sources like a tape-recorder (R-to-R) or a CD-player.

ECLL800 is pretty expensive so watch-out for that detail before digging in too deep.

rgds,

/tri-comp
 

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Yes this will be my first ever tube amp, so there is a bit of basics around tubes that i need to "refresh" before i start. There is not much in this one i trust to function as it is supposed to, so safety first, allways. all lytics are given subjects to be changed. i will keep this thread updated when i get going with this one :D ECLL800 is kind of expensive but there is no way around that, hopefully it will give something back :)

thanks!
 
.... not sure of their condition, probably bad.

Just measure the voltage at the common cathodes (Across the cathode bypass electrolytic). You should measure around 7 ~ 7,5V= with volume turned down if the ECLL's are OK.
Defective grid-1 cap's (C111/47nF & C108/22nF) may raise this voltage considerably and even destroy the ECLL's. Don't bother checking before replacing these cap's.

rgds,

/tri-comp
 
So far so good, tested out the transformer and at 230v in the output is 255v and 7v. So now i will sort out this, and order some components. This big alu elytic 100uf+50uf+50uf (C801, C802, C803) does those caps have a special funky name :p? actually never seen one before, what i can remember anyhow. except caps n pots after this amount of time, is there any other components that should really be checked before taking it further?
 
This big alu elytic 100uf+50uf+50uf (C801, C802, C803) does those caps have a special funky name :p? actually never seen one before, what i can remember anyhow.

Most of these multi-section caps I found in any shop or electronics distributor were roughly the same age as the ones I wanted to replace. Check date code!

I would replace them by separate caps of appropriate capacity and voltage rating, preferably 105°C types for longevity. But please, no duct tape constructions, find a mounting solution that looks satisfying from an engineering point of view. Isn't that difficult. :)

Greetings,
Andreas
 
Update:
changed all elyts and black cracked caps, checked rectifier and basic wiring. Brought it up to line voltage yesterday and the glow....all except the ECC85 in fm circuit, so something is not right there (either) one step forward hopefully, the problem is that i do not have any output (sound) so this is where all the fun begins, lots of possible faults i suppose. as this is my first ever tube amp, help is more than welcome :)
 
Okay, i did find the issue... faulty fuse (not tripped), shame on me :eek:. Grid caps where not changed but checked for shortout before testing the amp, this only becourse i had no idea if it would be a good investment, and i know now that it will be. never heard a tube amp before, 15mins and i am lost forever....totally. I listen mostly to psychedelic trance, and the clarity this brings to the music is incredible since all "channels" or sounds in a track tends to melt togehter and loose intensity badly. it is kinda sloppy done with the caps here, as i said before i had no idea what tubes where about so now i will give this some real love and some very good components since it busts all my other amps :rolleyes:. Cheers! :)

O yeah, the fm tuner.... it has a bad tube ECC85, i feel that it would be pointless to change it since i never going to use it so..... thats it, if anybody wounder.
 

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