Mod to an old radio

[Petman]

Hi!

Well, this is what's up: i have at home an old relic radio/LP player, from 1956 that was my grandfather's. It uses an EL84 in SE mode for output, together with a lot more tubes. It's a Siemens, but don't know the model right now.
I would like to know if it is possible to add a line in jack or something that would do the trick, without harming this little wonder, so that i can play my cd's on it thru a cd/md player.

Any sugestions?

Many thanks!

 

[dhaen]

Petman,

First of all, make sure the chassis is not live. It should not be (by design), as it uses the "E" series valves.
The problem is that safety standards were not good at the time of manufacture. If not already fitted, you may have to change to a 3 wire mains lead, and earth the chassis.
If that can be done, then just intercept the lead to the top of the volume control with your jack, take the shield connection of your jack to the bottom of the volume control.
Please be careful to keep your signal wiring away from live or hot components.

Cheers,

 

[EC8010]

Quaint CD

Of course it's possible. I assume that you are more concerned with the quaintness of the idea than the sound quality. The hardened old radio fanatics fit a modulator onto their CD player so that they can actually tune in to the CD player! (No, I don't have a diagram.) The alternative is to get at the selector switch and find the screened lead that goes to the pick-up arm, chop it, and connect it to a pair of phono sockets. Job done!

OK you will lose the record player, but, believe me you wouldn't want to let it loose on your records...

 

[Petman]

Ok, let see if i got it right: I'll use the vol control line out to the power tube as the input for the player, like a regular tube amp, right? Now, if i make it to just have no selection from radio and LP inputs...

I don't want to screw up this radio, as i have a few (ok one) LP of mine from Jean Michel Jarre that sounds great, and my mom has a lot of old records that bring her back to the youth days. And the sound is absolutely fabulous! The bass is clear and strong, the treble good and with a low volume, if i just get my hand close to the speaker the air vibes! It's something i never felt in any other type of amp (all SS).
BTW, any hints on how to get the hum out of it? is anoying at low volume....

Many thanks guys!

 

[Petman]

Guys!

The model is the K65, it has a tape recorder input at the back, the plug looks like a kind of PS/2. Any thoughts on the connections?

Thanks once again!

 

[EC8010]

Tape in

I expect your tape recorder plug is a DIN socket. It's probably a 3 pin plug though, so you will need to make up a phono to DIN lead. Screen is on pin 2, signal on pin 3. Check safety issues, but since it has a DIN socket, the chassis is probably safe.

 

[dhaen]

Petman,

Yes, the tape input socket is the best way.
You may need to attenuate the signal a little if the volume control is too vicious. But try without first.
The 3 pin DIN plug is the only DIN with logical pin numbering. Pin 2 is in the middle.

Cheers,

 

[planet10]

Tape DIN input... i often plug a CD player into the tape in and it works fine (with the exception that few of the old german radios i've collected are actually in full functioning order).

dave

 

[Petman]

I looked a bit more to the plug and it seems to be a 5 pin DIN, 4 holes around it and one in the middle. only 2 pins have contacts.. Maybe it's better to open it up a bit to see where the wires go.
BTW any thoughts on it's value? Not that i want to sell it.... just to have an idea as a collector's item.

Thanks!

 

[dhaen]

Petman,

If only 2 pins are wired, then you only need to determine which is ground. This can be done with a meter.

The value will depend on condition and rarity.

I don't know this model, but generally speaking:
If it is's cabinet is made of bakelite, an ealy plastic, often brown, then it will probably be worth more than wood. If it a bright colour, then more still.

You may be able to find out more by searching by model number. I'm sure someone will have resored another, and published details.

If you open and clean it, take great care with the dial glass. Only clean with a soft cloth, and clean water if you must. The markings often just wipe off.

Cheers,

 

[Petman]

Here's a pic:

http://users.skynet.be/albert.aerts/radio/pages/siemk65.htm

Not exactly the same as pictured, but very similar.

Thanks!

 

[EC8010]

Old radios

Petman, a good book for this sort of thing is "Electronic Classics" by Andrew Emmerson. Even if it is a 5 pin DIN, the audio connections will be as I've previously described.

 

[Petman]

Thanks for the book indication.
I was hoping that the connections where about the same, by the displacement they have...

Well, once more, many thanks guys! You're all OK!
Tubes really bring up the best in people