Tesla BS-20 and Cell2Jack

[prokoph]

Hello all

I recently (after 3 months of shipping!) received my Czechoslovak Tesla BS20 rotary phone. I do not have access to a phone line so I use a Cell2Jack to test out all of my phones. It is an adapter that converts a cell phones cellular signal into an analog signal using Bluetooth (it makes the phone calls through the cell phone, basically as if the analog phone was a headset, but you can use the analog phone to dial and hang up, there is a dial tone, etc).

Anyways, when I plugged this phone using my adapter into the Cell2Jack, I got a dial tone, but when I tried dialling, the dial tone got interrupted and started up again, and it also did not ring when I called my cell phone. Also, when I picked up the reciever after hanging up the first time, there was no longer a dial tone. I tested the Cell2Jack with another one of my rotary phones (American) and it worked fine (the Cell2Jack can read pulse dialling as well).

Is something wrong with the phone, or does the Cell2Jack simply not register signals from European phones? Should I contact the manufacturer and see if they know something about this?

Any help would be appreciated, thanks!

[countryman]

Euro rotary phones do not work fundamentally different from American ones. If you can neither dial out nor get a ringtone when called my guess is that the phone is not wired correctly. Do you have pictures of the terminals?

Did you get the phone shipped directly from Europe?

Edit to add:
https://www.telefonium.cz/telefonn%C3%AD-p%C5%99%C3%ADstroje-aut-%C3%BAb.php

Google (Chrome) will translate:
"The Bs20 device is equipped with the possibility of connecting up to 5 devices to the telephone line without the possibility of mutual interception (priority is given to the device that is connected closest to the line to the control panel)."
The set might have some special circuitry for the described function. I couldn't find a diagram yet... will keep looking.

[prokoph]

I'll send a photo of the interior soon. Yes, it was shipped from Europe, but not from the Czech Republic/Slovakia; it was shipped from Ukraine (I've been finding lots of Czechoslovak phones in Ukraine for some reason).

[LarryInMichigan]

You could do a quick experiment and disconnect the ringer.  If the ringer is incorrectly connected, or the ringer capacitor is shorted, you may experience the problems you described.

I have bought at least a few phones from Ukraine and Bulgaria.  Both countries used to have cheap postage rate to the USA.  Ukraine us a poor country, so people are selling what they can.  There are quite a few phones from western Europe and Australia for sale by sellers in the former socialist countries.  At the end of the socialist paradise perios, large quantities of goods, such as used telephones, from the capitalist imperialist west were imported to make up for shortages.

Larry

[prokoph]

I can't seem to find how to remove the cover for the phone. I can't seem to find any holes for a screw driver... Do you know how to get inside the mechanism?

[LarryInMichigan]

It looks like there are two screws from the bottom which screw into the top of the shell:


The screws might be hidden by labels on the bottom of the phone.

Larry

[countryman]

On German phones of that era the screws used to be covered to prevent customers from opening the set.
I pushed a darning needle into these plugs and pulled them out ;-)

On the other hand, when the phone is unopened, it's likely wired the proper way.

[prokoph]

Unfortunately, I don't have a screwdriver that fits so deep into that hole so I cannot unscrew it. Oh well.