Reel to reel recorders have their own innate charm. Therefore, when I saw an Aristona EW5504 reel tape recorder on a classifieds site, I immediately contacted the seller.

Aristona (as well as Radiola was), was a brand of Philips, active from 1950 to 1990, which marketed some products of the parent company, but with a cheaper price. The Aristona EW5504 reel recorder is in fact equivalent to the Philips N4504.
I was already repairing a Sanyo reel tape recorder, which I mentioned in this article. But I needed a working device, so I decided to buy this too.

Il venditore lo proponeva come funzionante, ma, quando l'ho portato a casa, questa affermazione era tutt'altro che vera!
Il registratore a bobine Aristona EW5504 aveva infatti parecchi problemi, forse a causa del prolungato inutilizzo. Ho contattato il venditore che, molto onestamente, mi ha restituito parte dell'importo che gli avevo pagato.

So I started repairing this recorder too!
Aristona EW5504 reel recorder problems
Unfortunately, the recorder presented not only one problem, but a whole series of independent defects.
In primo luogo la riproduzione audio si sentiva solo su un canale, mentre l'altro era quasi muto.
Then the counter didn't turn.

The power button lasted for a few cycles, then broke.
Finally, as if the other defects were not enough, the recorder did not record one of the two audio channels.
So I decided to open the recorder and start working on it.

Replacing the playback head
Ho innanzitutto verificato che il problema di riproduzione audio (un canale era molto più attenuato dell'altro) fosse attribuibile alla testina. Sulla testina di playback, ho invertito i cavi dei segnali sinistro e destro, ed il problema si spostava sull'altro canale. Ho quindi dedotto che la testina fosse difettosa. Fortunatamente, ho trovato un lotto di testine "new old stock" su eBay, così ho potuto sostituire quella difettosa.

La testina di playback (part number: 4822 249 20038 A1) è utilizzabile anche per altri registratori a bobine, oltre al Philips N4504 e Aristona EW 5504. E' possibile installarla anche sui Philips N4512 e N4515, nonché gli equivalenti Aristona EW 5512 e EW5515.
In the service manual, which I attach at the bottom of the page, the head is indicated as K2 / 102.

Counter belt replacement
Some belts have a bad habit: over time, they melt!
The problem with the counter not turning was, fortunately, solely attributable to the loose belt, but cleaning the entire recorder from the residues of the old belt was not at all easy.

The old belt had melted on several parts of the Aristona EW5504 reel recorder and also on the electronic board, which, moreover, was also very dusty.

Sostituzione dell'interruttore di accensione
Sfortunatamente, non sono riuscito a trovare l'interruttore di accensione originale. Ho acquistato un interruttore differente, ed ho dovuto adattare i supporti in modo da poterlo installare.

Replacing some capacitors to repair the recording section
To repair the recording section (one of the two audio channels was recording too low), I had to refer to the service manual (attached at the bottom of the page).
Dallo schema elettrico, ho notato che la tensione all'ingresso + dell'operazionale IC1 era quasi 0V, mentre avrebbe dovuto essere 8,2V. Ho trovato quindi che il condensatore C4 era in cortocircuito. Ho provveduto alla sostituzione di C4 e, per simmetria, anche di C104, l'omologo condensatore dell'altro canale.


The final test of the Aristona EW5504 reel recorder
After all these repairs, the recorder was back in great working order.
Ho provato a campione qualche condensatore elettrolitico e, purtroppo, ho notato che sono un po' fuori tolleranza.
This is, unfortunately, a clear signal: sooner or later a full recap will need to be done. In fact, electrolytic capacitors tend to degrade over time: losses increase, capacitance tends to go out of tolerance and some capacitors also short-circuit.
The amount of electrolytic capacitors on this device is quite large. Therefore, I will do this in the future, when and if it is really needed.

Documentation for Aristona EW5504 and Philips N4504 reel recorders
In support of this article, I am attaching the Philips reel recorder manual N4504 and the Philips N4504 reel-to-reel tape recorder Service Manual.

Bravo Amedeo, I am very envious of your great skills starting from the use of the c64.
Really many compliments
Thanks so much! Your comment makes me very happy!
Best regards .. really good ... you should dedicate yourself to the radio .. I speak to you as a radio amateur .. I hope your son .. follow you ... smart .. 73..da Gianni Samannà It9vxs ...
Hi Gianni. Thank you very much for the compliments, they make me very happy. I also like radios very much. I'm fascinated by old tube radios. Sooner or later I'll buy one. See you soon!
Caro Amedeo Valoroso.
Agradeço sua gentileza em postar ambos os manuais, dessa forma acredito será possível restaurar meu 5504.
Saudações desde São Paulo
João Elio
Dear João Elio. I am glad to have been helpful to you. Happy repairing!
oi amigo ... tenho um igual com problemas ... o sr conserta ??? e de sao paulo ???
Hello! Sorry, I am from Italy!