Telefunken Americana 5436 MX

[uglysteve]

Thank you Philipp.
That's the radio that I have the schematic posted above. I guess I should get a Radio museum membership. I will work on that.
Steve
Danke Philipp.
Das ist das Radio, das ich die schematische oben geschrieben haben. Ich glaube, ich sollte eine Radio-Museum Mitgliedschaft. Ich werde daran arbeiten.
Steve

[tcfkat]

Steve,

since a few weeks you don't need to be a member of radiomuseum.org anymore to get those schematics, the mandatory registration has been given up. Download is free, but limited to some schematics per day and so and so many schematics per month. Schematics are send to you by email and also you have to fill in a captcha. But if you use different email addresses, delete your local cookies and change your IP address you can virginize yourself and overcome this limit... don't tell anybody...

Greetz,
Eric

[uglysteve]

Eric,
I don't seem to be able to request a schematic, button is gray and won't work. I have not become a member because they publish your home address to other members. I don't like that.
Steve
Eric,
Ich scheine nicht in der Lage zu sein, eine schematische anzufordern , Button grau ist und wird nicht funktionieren. Ich habe nicht ein Mitglied zu werden, weil sie Ihre Adresse an andere Mitglieder veröffentlichen. Ich mag das nicht.
Steve

[Uli]

I have not become a member because they publish your home address to other members. I don't like that.

Don't agree with you!
See screenshot below: I'm logged in and this is what i see from a randomly choosen member:
- realname (made 2nd name unreadable)
- email (didn't take it on the screenshot)
- ZIP/hometown
- country

+ whatever information the member gives on voluntary basis.


  RM_Profil.jpg (Größe: 130,84 KB / Downloads: 176)


@Admins: Wenn dieser Screenshot schon zuviel Info ist (oder ich persönliches übersehen habe zu löschen), dann bitte weg damit!

[tcfkat]

Steve,

don't use the button, it won't work. Select on the right hand the schematic you want, possibly using the little scroll bar. Once selected appears on the left a strong magnified tiny portion of the selected scheme. Click into this scheme on the left side! Then a window will pop up asking your email address and so forth. Unfortunately you have to repeat this for every single page, you can't get a whole service manual at once. Keep in mind your quota, as said above.

Nite,
Eric

[uglysteve]

I have not become a member because they publish your home address to other members. I don't like that.

Don't agree with you!
See screenshot below: I'm logged in and this is what i see from a randomly choosen member:
- realname (made 2nd name unreadable)
- email (didn't take it on the screenshot)
- ZIP/hometown
- country

+ whatever information the member gives on voluntary basis.




@Admins: Wenn dieser Screenshot schon zuviel Info ist (oder ich persönliches übersehen habe zu löschen), dann bitte weg damit!



Thank you Uli, I was using the new member sign up page for my information. I guess I misunderstood.
Danke Uli, ich war das neue Mitglied Anmeldeseite für meine Daten erstellen. Ich glaube, ich missverstanden .



  A Capture Radio M.JPG (Größe: 34,24 KB / Downloads: 255)

[uglysteve]

Danke, es hat funktioniert.

Steve,

don't use the button, it won't work. Select on the right hand the schematic you want, possibly using the little scroll bar. Once selected appears on the left a strong magnified tiny portion of the selected scheme. Click into this scheme on the left side! Then a window will pop up asking your email address and so forth. Unfortunately you have to repeat this for every single page, you can't get a whole service manual at once. Keep in mind your quota, as said above.

Nite,
Eric

Thank you, it worked.
Danke, es hat funktioniert.

[uglysteve]

Der Bass Potentiometer hatte eine schlechte Reparatur in der Vergangenheit. Die Kohlebürsten wurden mit Messingnieten ersetzt. Es ist 16 meg Ohm Doppel Potentiometer, die nicht verfügbar zu sein scheint. So repariert ich das Potentiometer.

The bass potentiometer had a bad repair in the past. The carbon brushes were replaced with brass rivets. It is 16 meg ohm dual potentiometer, that seems to be unavailable. So I repaired the potentiometer.

  pot1.JPG (Größe: 39,61 KB / Downloads: 206)

Ich bestellte 2mm Bleistift Graphit aus der Tschechischen Republik. Sie nahmen mehrere Wochen ankommen. Ich bestellte auch einige Graphitbasis leitfähigem Kleber. Ich benutzte ein Dremel Werkzeug als Dreher und ein Juwelierschraubenzieher als Schneidwerkzeug . Ich habe neue Bürsten und kleben sie auf den Halter in.

I ordered some 2mm pencil graphite from Czech republic. They took several weeks to arrive. I also ordered some graphite based conductive glue. I used a Dremel tool as a lathe, and a jewelers screwdriver as a cutting tool. I made new brushes, and glue them in to the holder.

  pot2.JPG (Größe: 45,75 KB / Downloads: 207)
   

  pot5.JPG (Größe: 36,96 KB / Downloads: 204)

Es funktioniert großartig , kein Lärm, wenn sie einge.
It works great, no noise when turned.

[Vagabund]

Great repair.
Hopefully the pencil graphite won't be too soft, but the future will show.
But such solutions will work for years usually.
You did a great job.

[tcfkat]

Yes, nice work! The hardness of the pencil is 5B, which is rather soft. Maybe something from 2H to 5H would have been better. Anyway, this knob isn't as often used as the volume.
Didn't you had an old potentiometer to scrap just for the brush?

Regards,
Eric

[uglysteve]

Ich entschied mich für die weiche 5b Härte, weil ich nicht wusste, wie schwer es sein sollte, und ich würde lieber zu weich verwenden. Wenn es verschleißt, kann ich die Bürste ersetzen. Wenn zu hart ist, kann es Teile beschädigen ich nicht ersetzen kann. Ich habe nicht alle alten Potentiometer zu verschrotten.

I chose the soft 5b hardness, because I did not know how hard it should be, and I would rather use too soft. If it wears out, I can replace the brush. If too hard, it may damage parts I can't replace. I don't have any old potentiometer to scrap.

[uglysteve]

My next problem to solve is low output of the right amplifier. I put a 1 KHz signal into the tape input. This is my output at the external speaker output.

I have swapped the tubes between right and left, no change. I swapped left and right inputs to the amplifier, and the problem does not change. So it is in the amplifier.
Mein nächstes Problem zu lösen, ist geringer Leistung des rechten Verstärkers. Ich habe ein 1 kHz-Signal in das Bandeingang. Dies ist mein Ausgang an den externen Lautsprecher ausgegeben.

Ich habe die Rohre zwischen rechts und links, keine Änderung getauscht. I vertauscht linken und rechten Eingang in den Verstärker, und das Problem nicht ändert. So ist es in dem Verstärker.

   

[Vagabund]

Hi Steve,

I would check if there are Vitrohm resistors, or you can try the hum test (if it's so called). Radio plugged into the separating transformator then with fingercontact on the control grids. Then there should be noise of hum hearable in the speakers. Start on the EL95. Be careful and stay away from the plate voltage. I think the problem is anywhere in the pre stage. Between hum and silence should be the failure.
It's my opinion, maybe one of the professionals have other better solutions... but I would try this way.

Good luck.

[uglysteve]

Behoben. Gefunden eine gebrochene Spur auf dem Verstärkerleiterplatte .

Fixed it. Found a cracked trace on the amplifier printed circuit board.


  Cracked trace1.JPG (Größe: 51,28 KB / Downloads: 124)



  Fixed.JPG (Größe: 37,03 KB / Downloads: 121)

[uglysteve]

Hi Steve,

I would check if there are Vitrohm resistors, or you can try the hum test (if it's so called). Radio plugged into the separating transformator then with fingercontact on the control grids. Then there should be noise of hum hearable in the speakers. Start on the EL95. Be careful and stay away from the plate voltage. I think the problem is anywhere in the pre stage. Between hum and silence should be the failure.
It's my opinion, maybe one of the professionals have other better solutions... but I would try this way.

Good luck.

Thanks for the tip. I found the problem with an ohm meter, there was 39 Kohm in a trace connecting a preamplifier tube heater
to a board with some capacitors on it.

Danke für den Tipp. Ich fand das Problem mit einem Ohm-Meter, gab es 39 Kohm in einer Spur einen Vorverstärker Rohrerhitzer auf einem Brett mit einigen Kondensatoren auf sie zu verbinden.

[Vagabund]

Good job.

Had such a problem in a, let me remember, I think, it was either an Othello 60 or a Tannhäuser 60. One of the plate voltage traces was broken, so that one of the ECC83 of the preamp had no voltage on their plate.

[uglysteve]

Good job.

Had such a problem in a, let me remember, I think, it was either an Othello 60 or a Tannhäuser 60. One of the plate voltage traces was broken, so that one of the ECC83 of the preamp had no voltage on their plate.

This is the trace.

  Crack trace.JPG (Größe: 89,38 KB / Downloads: 100)

[Vagabund]

Seems not to be the filament, it more seems to be the cathode.

[uglysteve]

Seems not to be the filament, it more seems to be the cathode.

Thanks for the correction.

[tcfkat]

A crack nearby a connector pin is the result of mechanical stress due to transport or handling. You should not only resolder it, but also place a small copper wire over the track to reinforce it. Also check the other connector pins for damaged or nearly damaged tracks.

Btw., nice generator, HP 3325A?