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REN booster DIY

Started by dsk, August 10, 2019, 10:31:01 AM

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dsk

As usual I like to make my prototypes, this time I made a ring detector connected to a ringing generator to increase the REN load.  Inspired by older systems with grounded ringing I use a third wire (instead of ground). All my phones has ringer capacitors, so I do not need a main capacitor as used in the British system.


I have used a DC-DC solid state relay: SSR HHG1D 1d-0/032F-20  And for ringing a Power Dsine PCR-SIN03V12F20-C making 20Hz 70V from 12VDC.

And yes it works, I have made one earlier, but used an old relay, but that has a higher REN load.
I measured the REN load to 0.26REN

dsk

markosjal

#1
WOW! Very Cool Thank you!

Now I can have so many mechanical bells that I vibrate the floor!
Phat Phantom's phreaking phone phettish

RB

DSK, you keep coming up with cool ideas. 8)
Thank you!
Keep it up. this sight needs you!!! :)

dsk

I love that good feedback ;D
And today the Norwegian museum sent me a question for help, even when I just could give them a little help I'm pretty proud ;D 8)  to be asked.


dsk

HarrySmith

Wow! That is impressive, if a telphone museum calls YOU for help! I don't blame you for being proud. We are proud you are a member here and sharing all this great stuff and knowledge with us. Thanks.
Harry Smith
ATCA 4434
TCI

"There is no try,
there is only
do or do not"

dsk

I have been working further on this idea. 
I have tested it as described over, and it works great, but I need the third wire.

Now have put in another relay and a diode, the diode stops the ringinging signal, and the relay puts out the new signal on the lin, but if you lift off the receiver in the start of a ring, the line will not sence that you have gone off hook before the ring ends. In the meantime the ringer generator will send out the signal to the off hook phone.

Any ideas about if this is OK?
dsk

countryman

I remember I tinkered with phones in the eighties and built an experimental exchange for them. I used transformed 50 Hz AC for ringing, because that was what I had  ;) and the phones took no damage from it. A ring cycle would continue also when the handset was lifted up. That would give a loud buzz in the receiver. I used a 470 ohm series resistor for ~ 40V AC and - as mentioned - the phones survived. If that practice was safe and recommendable is a totally different question!
On a "real" exchange, the ringer AC adds to the DC voltage, which is always present and triggers a relay immediately when the handset is lifted.

dsk

I guess that will be OK too, the inverter will probably just stop of the wrong load, a transformer with ringing current would probably be tougher because it keeps on delivering ...

dsk

Dan/Panther

dsk;
Always enjoyable to read your posts. Keep em coming.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

dsk

Thank you D/P   :)

I have tested it out further, and the relay was to sensitive so it could trig on dialing, solved by putting in another zener back to back with the one I already had there. 

dsk

dsk

This circuit is sensitive to line polarity!
dsk

markosjal

DSK,

What was the outcome of this final version posed here?
Phat Phantom's phreaking phone phettish

dsk

Works fine on Linksys ATA's, but it does not sense that you go off hook before the ring is ended. On my old electro-mechanical switch I got problems due to polarity reversal, but it is actually not needed on that one.

dsk

markosjal

#13
Probably best to stick to th 3 wire version thern.

I am installing it into a wooden phone with Rorary dial, DialGizmo and Obi200, making it a Google Voice Phone (or other direct VoIP. Since this WE ringer is from early 1900s it takes a lot of power to ring it the way it should ring.

I do not mind the third wire in the phone, as in  this case it is INSIDE the phone. The phone will actually become a POE ethernet device. . That third ringing wire will never see the outside of the phone. 

I suppose in other circumstances, like where other phones may have this internally installed,  one could power it with 24V over yellow/black pair then use a 12V buck converter inside the phone.

Phat Phantom's phreaking phone phettish

dsk

Quote from: markosjal on January 01, 2021, 03:36:27 PM
Probably best to stick to th 3 wire version thern.

I am installing it into a wooden phone with Rorary dial, DialGizmo and Obi200, making it a Google Voice Phone (or other direct VoIP SInce thhas WE ringely 1900s it takes a lot of power to ring it the way it should ring.

I do not mind the third wire in the phone. The phoe will actually become a POE ethernet device. . That third ringing wire will never see the outside of the phone. 

I suppose in other circumstances, like where other phones may have thic internally intalled,  one could power it with 24V over yellow/black pair then use a 12V buck converter inside the phone.


The best is to stick to the 3 wire version, but you have to make your phones use 3 wires in the jack.  Most old phones has that possibility.  Norwegian phones usually has the Marking EB or EK for the third wire.  It is even possible to do on the first Norwegain push button phone, (tastafon) but you have to study the diagrams.  Later phones does not need more ring current.  :)