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Build your own Ring Generator for Testing!

Started by DavePEI, April 27, 2011, 08:06:28 AM

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DavePEI

Hi All:

I have several ways of testing the ringers for phones, but one of the simplest I built several years back using a Black Magic LSN 12 - 86 module. There is also a 5 volt version, and a 24 volt version made.

These modules, available from http://www.camblab.com/ are great devices, in a potted case, .5" high x1.5" wide x1.5" long.

You will occasionally see these on eBay for a very good price. If I remember correctly, I bought two for $7 ea.

All that is needed to make a great portable ring generator, is the module, a small Radio Shack 3 .25" long x 2 " x 1.5" case, a momentary contact push-button, a 23A Cell Battery Holder, 23A 12 v battery, 330 ohm 1/8-1/4 watt resistor, a modular socket out of a cheap scrap phone, and a pair of terminal posts.

No need for a PCB - simply mount the module with double sided foam tape upside down in the case, and solder directly to the 4 pins.

Wiring is very simple. Neg. from the battery goes  to the - terminal on the generator. Pos. from the battery goes via the momentary contact push-button to the positive terminal of the module.

One ~ output from the generator goes directly to the red lead of the modular socket (mounted below the posts), and to the red terminal post. The other goes from the other ~ terminal via the  330 ohm resistor (for short circuit protection - I forgot to mention this in my original post) to the green lead of the modular socket, then on to the remaining terminal post.

Plug in a modular phone, or use clip leads to the red and green wires from a non modular phone, press the button, and if the phone is wired for non-party lines, it will ring away!

Each 23A battery will last several months under average use.

This makes a great portable ring generator to test phone ringers and as an aid to wiring them correctly without connecting them to a phone line (no-one would test them out directly on a phone line, would they? :) ).

Most of the time, I use my much larger Radio Shack tester to set up phones, or test it on my 555 or switching demo, but this unit comes in very handy at times due to its small size and portability. It will produce up to 5 REN with 86 volts AC 30 cycle.

Just thought I would post this today, as I had it out changing the battery. It is a great adjunct to your toolbox, and indispensable if you don't have another ring generator!

Photo below...

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

LarryInMichigan

I sometimes use a magneto for testing ringers.

Larry

GG


Is there any way to adjust the ringing frequency output?

Reason why is: all those pesky party line ringers (harmonic/decimonic ringers) that turn up in AE, SC, and Kellogg phones, that otherwise have to be de-tuned and still don't work quite right. 

The way to use it would be:  Across tip & ring, wire an AC relay in series with a capacitor, that will close during ringing.  Then connect the external ringing generator across the spare pair (yellow & black), and wire the frequency ringer across yellow & black in the phone.  (It may also be possible to use tip to ground or ring to ground for the ringer, if both AC signals can share one wire in common without trouble.)

With an adjustable frequency version, you might have a little trimmer potentiometer in the unit, and you'd hook up the phone and adjust the trimmer until the phone was ringing nicely. 

Kevin Lane

Question:  Can one of these Black Magic modules be used to create an AC ringer current on a PBX (Rauland Telecenter 21) that only has a 12 volt DC ringer circuit?  I ask because I would like to use a WE2500 in place of the standard issue Rauland phone.

Why do I want to do this?  Because I want my phone to ring - not chirp!

DavePEI

Quote from: GG on April 27, 2011, 09:01:10 AM

Is there any way to adjust the ringing frequency output?

Reason why is: all those pesky party line ringers (harmonic/decimonic ringers) that turn up in AE, SC, and Kellogg phones, that otherwise have to be de-tuned and still don't work quite right. 

The way to use it would be:  Across tip & ring, wire an AC relay in series with a capacitor, that will close during ringing.  Then connect the external ringing generator across the spare pair (yellow & black), and wire the frequency ringer across yellow & black in the phone.  (It may also be possible to use tip to ground or ring to ground for the ringer, if both AC signals can share one wire in common without trouble.)

With an adjustable frequency version, you might have a little trimmer potentiometer in the unit, and you'd hook up the phone and adjust the trimmer until the phone was ringing nicely. 

Not as far as I know - you can order versions in different frequencies, but I don't think you can make one adjustable...

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

Owain

Quote from: Kevin Lane on April 27, 2011, 09:03:03 AM
Question:  Can one of these Black Magic modules be used to create an AC ringer current on a PBX (Rauland Telecenter 21) that only has a 12 volt DC ringer circuit?  I ask because I would like to use a WE2500 in place of the standard issue Rauland phone.

Why do I want to do this?  Because I want my phone to ring - not chirp!

The LS works off 12 Volts. Not sure if it would be compatible. Have you ascertained the Rauland uses 12Vdc ringing and on what pins?

http://www.camblab.com/datashts/lsnspec.pdf

gpo706

Or get a linesmans ringing set, or a PBX   :)
"now this should take five minutes, where's me screwdriver went now..?"

DavePEI

#7
Quote from: gpo706 on April 27, 2011, 06:27:20 PM
Or get a linesmans ringing set, or a PBX   :)
But, I'd like to see you fit a PBX into a tool kit! This makes a very portable light weight generator that takes up very little room in a kit - far less room and far lighter than any of the above options. It will literally fit in a pocket.

I also have a BK tester, as well as various PBXs I could use, but this is ideal for quick tests in and out of the workshop.

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

Jim Stettler

#8
I have the black magic chip somewhere. I was planning on installing it in a toner housing for ease.
Magnetos work well for ringer teting.

Another good tester is a "Radio station test phone" (553?) these are a metal can with a magneto and batteries. They were designed for use with radio station lines, locally the Bell guys at fort Carson, CO and the Air Force Academy used them for testing purposes. The Ft Carson guy showed me how to use them as a tester and I used to have 4 from the estate of the Air Force Academy guy.


I may still have some packed somewhere.
Jim
You live, You learn,
You die, you forget it all.

camblab

#9
Cambridge Electronics Labs here: we manufacture the Black Magic
Ringing Generator.

A detailed technical description of the use of the device and
how to engineer it into equipment may be found at

http://www.camblab.com/lit/trix_v_2.pdf

If you want to save yourself some assembly effort, you
may use our ATRA-1 which contains both a ringing generator
and ring-trip circuit; feed it with 12 Vdc and ring your
phone.   As these were custom built as an accessory for
a now discontinued US Robotics product, we have a few left
and the price is the same as the ringing generator: $29.00.

http://www.camblab.com/datashts/atraspec.pdf

If you require a hotline device (bi-directional ringing
between two phones as soon as one goes off hook) use our
Quiklink, either Economy model (cadence 2 seconds on, 2
seconds off) or Standard model (selectable ringing
cadences).

http://www.camblab.com/consumer/ql_1_2.pdf
http://www.camblab.com/consumer/of_ql_us.pdf

E-mail us any questions: camblab@attglobal.net.   We also
repair antique phones.   

DavePEI

#10
Hi All:

I have a number of new PowerDSine ring generators available:

P/N PCR-SON03V12F20-C
Vin: 12 VDC
Vout 70V RMS
P Out 3 W RMS
Frequency 20 hz/cycles

The module has 5 wires:

V+ (12V) red
V- (GND) black
RNG1     blue
RNG2     white
INHIBIT  yellow

INHIBIT can be left floating. If pulled to +5V from GND, the output ring
signal is inhibited.

These are the same size as the Black Magic inverters and will work in their place in the above device. As with the Black Magic generators, these can be secured in a device using double sided tape on the back. As with Black Magic generators, a 330 ohm resistor should be run from one AC lead to act as short circuit protection to protect the device.

Price? $5 ea plus postage.

I also have one spare Black Magic 5 volt inverter which I will sell for $10.

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

DavePEI

#11
Eight of these devices have been sold at $5.00 ea. See specs above. Postage Approx $3.80/3, $2.20/1. I have two left. I do have some more coming, but their price will be a bit higher. Meanwhile the price on this lot stays the same. I can usually get these to the post office within 24 hours or less.

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

DavePEI

#12
Quick Diagram of a Simple Battery Powered Generator:

It is a quick and dandy circuit - perfect for carrying in your toolbox for quick tests, or for taking to shows to check out that prospective purchase. Your large ring generator/phone analyzer/Panasonic KSU can stay home.
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

DavePEI

By the way, If you plan to build one as I did in a small case, you can find 23A battery holders on eBay from $1 to $3, 23A (Also known as: A23 / LRV08 / L1028 / RVO8 / 23A / MS21 / MN21 / E23A / K23A / V23GA / GP23A / 8LR932 / 8LR23 / VR22 / 8F10R / EL12) batteries in your local dollar store. Switch can be any momentary spst pushbutton, and case from RS or eBay or your junk box.

Mine cost me about $10 total (even with inflation, shouldn't be over $20 including generator today even with everything bought new as long as you get your generator at the amount I charging).

Dave
The Telephone Museum of Prince Edward Island:
http://www.islandregister.com/phones/museum.html
Free Admission - Call (902) 651-2762 to arrange a visit!
C*NET 1-651-0001

TelePlay

#14
All I have to say is "why the heck did it take me 10 years to find a simple ring generator that just rings a telephone on stage!"

The batteries arrived today so I hooked everything up with alligator jumper leads according to Dave's schematic as shown in the picture below and it worked! (no switch for now other than attaching the ground wires together with the alligator clip to complete the circuit and no resistor because I knew the ringers I would try worked)

Rang a 127 extension ringer, a 500 and a 302 at 20Hz just fine.

Now all I have to do is build the box. All parts in total to make a Box like Dave had in his photo will cost me about $18. Quite simple and elegant and cheaper when compared to a Teletone 4, Panasonic 616 or a Tellabs generator when all one wants to do is ring a phone or test a ringer. I'm 10 years in the waiting impressed.  :D

Thanks, Dave . . .