Author Topic: Pulse to tone converter  (Read 2048 times)

Offline Telephone_Singer22

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Pulse to tone converter
« on: December 17, 2016, 03:06:10 PM »
Has anyone ever succeeded in making their own pulse to tone converter to use on VOIP services and CNET? If so, would you be able to provide me a simple schematic and list of supplies? I just don't want to shell out $75 for one, or pay $50 to wait for one to come from Japan.

Thank You

Offline bnaOldPhones

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Re: Pulse to tone converter
« Reply #1 on: April 13, 2017, 01:20:47 PM »
I think those typically have 8-bit microcontrollers on them; you would need source code and a way to program the part as well as a schematic.

Offline Jim S.

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Re: Pulse to tone converter
« Reply #2 on: April 13, 2017, 02:03:55 PM »
I advise any collector that needs to convert pulse to tone, to use a Panasonic 308/616 KSU for your converter. The cost is about the same as a single phone converter, and you can use it for testing and intercom as well as pulse conversion.
JMO,
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Offline dsk

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Re: Pulse to tone converter
« Reply #3 on: April 15, 2017, 03:12:26 AM »
I have not made this:  http://bygselvhifi.dk/projects/telephone-pulse-to-dtmf-converter/   but it is interesting.  So far I prefer to by a working solution.  :)
dsk

I have even got a regular New York number :-) 646 570 1796

Offline Phonesrfun

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Re: Pulse to tone converter
« Reply #4 on: April 16, 2017, 02:00:29 AM »
I don't know why so many people have had such bad results with pulse to tone converters, but on the other hand I have never used one so maybe I should shut up.  (But I won't)


The basic act of converting pulses to tones should not be rocket science.  Maybe some have just gone too far out trying to incorporate speed dial and certain conditions to create star and pound (* and #) symbols.  Bad move in my opinion.  I think some have tried to sense the use of the dial with the non 500 way of shunting the line.  That means that type of converter automatically will have trouble working on a 500.


I also think they assume anyone with no wiring experience can just know where and how to connect them based on real crappy instructions.  Also a bad assumption.  I think someone trying to connect one internally to a phone needs to understand the way the phone really works and not just "connect red and green to L1 an L2". 


Bottom line is that I am very unimpressed by what I have heard.  Too bad that rotary systems are fast going by the wayside.


I happen to have a cable company that provides an ATA that does sense pulse dialing.  I also have a Panasonic 616 which also converts pulse to tone.  I have a C*Net line with a Motorola VT 1005 (?) ATA that also recognizes pulse.  Finally, I have a Google Voice line that I am using a Grandstream ATA that I have also set to recognize pulse dialing.  So, I have no need for one of those converters, but my heart goes out to those who need one and can't seem to get one of the ones that are available to work.


-Bill G

Offline dsk

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Re: Pulse to tone converter
« Reply #5 on: April 16, 2017, 04:06:06 AM »
I have never got my fingers into an ATA understanding pulses, but the Dialgizmo works on most of my phones if I can live with single digits only. 

As I remember the only unit it never would allow dialing is an Ericsson exchange, but this was never a problem for me, I have other ways too, Panasonic  KXT616 etc.

I have even got a regular New York number :-) 646 570 1796

Offline KaiserFrazer67

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Re: Pulse to tone converter
« Reply #6 on: April 16, 2017, 05:52:20 AM »
I have a Rotatone in my Kellogg Redbar and it works fine.  I bought a Dialgizmo for a friend of mine and it works just fine on his cable VoIP line.

A Panasonic 308/616/1232, or an ATA or C*Net (whatever those last two are) are fine for the hardcore phone collector, but a good section of the population just wants a single-phone solution "so that we can use Grandma's old dial phone again" on their cable line/Magic Jack/what-have-you.  Getting a Rotatone installed is for them.  The Dialgizmo is even simpler, since it's literally plug-and-play. 

Most people, myself included, can't wrap their heads around how a Panasonic 616 even works, much less how to hook it up and use it.  Those people I described in the above paragraph don't have the technophiliac giga-geekery needed for that.  As for me, my own very limited tech-school training in electronics dealt with basic computer circuitry from the early 1990's, and never delved into telephony.  Most of it went into "/dev/null" since I eventually went into regular factory work.  I remember some things, and I can read a schematic (for the most part), but I am just now really starting to wrap my head around how a telephone actually works electronically.  A PABX is beyond my expertise at this point, even one which is supposedly more-or-less "plug and play" like the 616--I'm lucky I even know what one is, to tell the truth.  I've looked them up on eBay and even those selling them don't have much to say other than "I plugged it in and it lights up, didn't test, don't know how it works, yadda yadda yadda."  I even downloaded an instruction manual I found online and couldn't figure out how to apply it to a phone collection.  Since I do intend to expand my collection, I will probably eventually have to invest in one; but I'm going to have to be taught how to install and use it, whether through a thread on this forum explaining it, or whatever.

As for building a pulse-to-tone converter, I don't believe there is a cheap DIY solution, at least for a single unit.  Dusting the cobwebs off of memories almost 30 years old here:  I (vaguely) remember programming chips in tech school, making basic logic circuits to make a rudimentary calculator, and other things to that effect.  It seems to me that you'd have to program a chip to read the pulses, convert them to a DTMF tone, generate the corresponding tone, and then burn that info onto a chip.  Not to mention making a circuit board on which to mount the chip and the other electronic components necessary to make it work effectively like diodes and such, and the connections to hook it into the phone.  I'm sure there is software and kits available to make your own; but if you only want one, as far as I can tell it might be much cheaper to buy one already made.  If you wanted to make your own, you wouldn't be able to stop at one if you wanted to get your money's worth out of doing so.

EDIT:  To give you some idea of the complexity involved, I've attached a photo of the guts of a Dialgizmo.
« Last Edit: April 16, 2017, 06:13:38 AM by KaiserFrazer67 »
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Offline Jim S.

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Re: Pulse to tone converter
« Reply #7 on: April 16, 2017, 09:49:17 AM »
A 616 is plug and play.
 Install the unit upright.
Plug a couple of phones in one of the 16 ext.and turn on the unit.
 Dial from 1 ext. to another and that phone will ring.
If you want an outside line , plug your telephone line  in to 1 of 6 CO jacks and  now you can dial 9 for an outside line.

JMO,
Jim S.
You live, You learn,
You die, you forget it all.

unbeldi

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Re: Pulse to tone converter
« Reply #8 on: April 16, 2017, 09:51:39 AM »
The entire difficulty in the pulse-to-tone converters is the power requirements of the converter circuit, the semiconductors involved.   For good reason, the idea is usually to not require additional power than what the telephone local loop provides in the 48VDC line level.   You don't really want another cord coming out of a telephone for power.   Unfortunately, the available power on a pair can vary greatly today, despite the standards that do exist.  Line noise, e.g. high-frequency components from electric appliances and other gadgets close by, is another aspect that is impossible to predict, and these little converters don't have much protection against any of that.

I have built several converters and dial pulse timers on breadboards with Arduino processor boards, and it was easy to make them work with stable power, from a separate supply.  If I were to sell any, I would also design them with a separate power supply, so that they should be installed at the wall jack or network interface.

I have to disagree, that a Panasonic is too difficult to install for many people.  That would be true only if those people also cannot install an answering machine. I agree, some can't hack that, indeed. Line in, telephone out.  It is that simple to install a Panasonic system.  Just a little bigger, and more jacks to select from.  With today's phone trees to navigate for most service requests almost everywhere, it is hard to conceive that somewhat can't dial 9, or 81, to make an outgoing call.

Quote
As for building a pulse-to-tone converter, I don't believe there is a cheap DIY solution, at least for a single unit.
The parts really only cost a few dollars.  A complete Arduino processor board can be as cheap as a dollar or two.  I think I paid less than $10 for a lot of five some time ago, and these don't get more expensive with time.  The cost is in the programming expertise of course.   But frankly, counting pulses is easy !  Generating tones can be done with existing libraries, it is rather plug and play. IIRC, there are DIY projects available online.





Offline KaiserFrazer67

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Re: Pulse to tone converter
« Reply #9 on: April 16, 2017, 08:23:07 PM »
The entire difficulty in the pulse-to-tone converters is the power requirements of the converter circuit, the semiconductors involved.   For good reason, the idea is usually to not require additional power than what the telephone local loop provides in the 48VDC line level.   You don't really want another cord coming out of a telephone for power.   Unfortunately, the available power on a pair can vary greatly today, despite the standards that do exist.  Line noise, e.g. high-frequency components from electric appliances and other gadgets close by, is another aspect that is impossible to predict, and these little converters don't have much protection against any of that.

I have built several converters and dial pulse timers on breadboards with Arduino processor boards, and it was easy to make them work with stable power, from a separate supply.  If I were to sell any, I would also design them with a separate power supply, so that they should be installed at the wall jack or network interface.

I have to disagree, that a Panasonic is too difficult to install for many people.  That would be true only if those people also cannot install an answering machine. I agree, some can't hack that, indeed. Line in, telephone out.  It is that simple to install a Panasonic system.  Just a little bigger, and more jacks to select from.  With today's phone trees to navigate for most service requests almost everywhere, it is hard to conceive that somewhat can't dial 9, or 81, to make an outgoing call.

The parts really only cost a few dollars.  A complete Arduino processor board can be as cheap as a dollar or two.  I think I paid less than $10 for a lot of five some time ago, and these don't get more expensive with time.  The cost is in the programming expertise of course.   But frankly, counting pulses is easy !  Generating tones can be done with existing libraries, it is rather plug and play. IIRC, there are DIY projects available online.
Well, that's still a lot more than I knew before.  What little I've seen online (so far) regarding the 616 has been confusing to me.  Remember that I'm still very much in the learning phase regarding this hobby.  I'm sure I'll look back on this several months from now and laugh and shake my head at how stupid I seemed...  ::)

As for building a pulse-to-tone converter, also remember I've been out of the electronics scene for a good number of years.  I'm sure parts have gotten much, much cheaper than they were before; plus so much has improved since then, it's mind-boggling.  I'm glad to know that a DIY converter isn't the tough, expensive project I thought it would be.
-Tom from Oakfield, Wisconsin --  My CO CLLI & switch: OKFDWIXADS0--GTD-5 EAX

"Problems are merely opportunities in workclothes." -Henry J. Kaiser

Offline ThePillenwerfer

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Re: Pulse to tone converter
« Reply #10 on: April 18, 2017, 06:07:37 AM »
I've recently made one. 

I came across details of this device, which uses an ATTiny85 micro-controller, some months ago but it was skimpily documented, and what there was was American, and gave no details of how to get the code onto a micro-controller.

I finally managed it and it works very well. It does have limitations though.

Firstly it needs fitting inside the telephone, which involves some (reversible) mutilation and secondly the PCB is rather large. What it does have going for it is being dirt cheap: the first one cost about £5 and subsequent ones about £1.50.  Neither does it have any problems with telephones fitted with electronic transmitters.

I've only used it on my ATA as I'm far too upright a citizen to connect it to a PSTN line.  In fact I've no need to as my supplier still supports LD.

Details (code, diagrams, links to orginal sources and instructions) are  here.


EDIT 8 July 2017

Following recent discussions about problems with broken links in the future I've attached the information below.

The PDF file contains background and instructions and the ZIP diagrams, micro-controller code &c.
« Last Edit: July 18, 2017, 08:41:29 AM by ThePillenwerfer »

Offline poplar1

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Re: Pulse to tone converter
« Reply #11 on: April 18, 2017, 07:27:48 AM »
"C'est pas une restauration, c'est une rénovation."--François Martin.

Offline ThePillenwerfer

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Re: Pulse to tone converter
« Reply #12 on: April 18, 2017, 09:03:19 AM »
Thanks for that.  I was trying to shorten the link in accordance with the Rules and obviously made a mess of it; I've now done it correctly.
« Last Edit: April 18, 2017, 09:21:44 AM by ThePillenwerfer »

Victor Laszlo

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Re: Pulse to tone converter
« Reply #13 on: April 18, 2017, 03:48:39 PM »
"A Panasonic 308/616/1232, or an ATA or C*Net (whatever those last two are)" 

Google will help, if you need answers...

https://en.wikipedia.org/wiki/Analog_telephone_adapter

There is no such thing as "a" C*NET.  "The" C*NET is a system of telephones and switching equipment, tied together by the internet, for the pleasure of telephone enthusiasts the world over.  It's "ham radio without the radio, for telephone hams."

https://www.ckts.info/

"... but a good section of the population just wants a single-phone solution "so that we can use Grandma's old dial phone again" on their cable line/Magic Jack/what-have-you."

Exactly why we here recommend the Panasonic KSU's, because they, by default, (or inadvertently/providentially, one might say) provide the conversion needed at a very reasonable price. They also allow the user to provide his own Panasonic multi-line telephones for advanced programming and functionality.  An "added bonus" as they say on TV, is that you can use ALL your telephones in a personal system, and demonstrate to friends and family how they dial, ring and talk, without tying up your outside line. 

"Most people, myself included, can't wrap their heads around how a Panasonic 616 even works, much less how to hook it up and use it.  Those people I described in the above paragraph don't have the technophiliac giga-geekery needed for that. 

"Most people" ???  I disagree.  There are jacks labeled "TEL" and there are jacks labeled "CO"  TEL means telephone and CO means Central Office (as in, the source of your outside dial tone.)  Plug in your collection, either one phone per jack, or many phones per jack, and connect a cord from the CO jack to your dial tone, and it will work in its default mode. No programming or giga-geekery required.

"A PABX is beyond my expertise at this point, even one which is supposedly more-or-less "plug and play" like the 616--"

A Panasonic key system is not a PABX, in the strictest terms.  They are plug & play, as described above.

"I'm lucky I even know what one is, to tell the truth."

I can't help you with a personal lack of optimism.  You need to be more self-assured.

"I've looked them up on eBay and even those selling them don't have much to say other than "I plugged it in and it lights up, didn't test, don't know how it works, yadda yadda yadda." 

That's all you need to know. Ebay sellers say those sorts of things to avoid liability should an item not work properly. However, they are simple and cheap. Join a club, go to a meet, ask the seller to demonstrate its viability, and buy one. Or buy one from a trusted source such as the folks on this or other forums.

"I even downloaded an instruction manual I found online and couldn't figure out how to apply it to a phone collection."

See above.  Plug in the phones. Plug in the dial tone. Voila.

"Since I do intend to expand my collection, I will probably eventually have to invest in one; but I'm going to have to be taught how to install and use it, whether through a thread on this forum explaining it, or whatever."

See above.
« Last Edit: April 18, 2017, 04:06:39 PM by Victor Laszlo »

Offline andy1702

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Re: Pulse to tone converter
« Reply #14 on: April 18, 2017, 03:52:20 PM »
I agree with Jim, a Panassonic 616 is definitely the way to go. If you use one of these PBXs then you can connect both an incoming POTS line and also a C*Net line from an ATA. The Panassonic will convert pulses to tones so you can use a dirt cheap PAP2T ATA for C*Net and don't have to invest in the more expensive Grandstream 502 ATA, which is just about the only one that can handle pulse dialling.

I have a couple of Panassonic 616s here that I use for taking working phone systems to local shows. However at home I use a BT Relevation, which basically does the same as the Panassonics.

The problem with Dial Gizmos / Rotatones etc is that you often have to modify how you dial a number. One of them (I can't remember which one) waits for the dial to get back to the 'normal' position then counts up the pulses and only then gives out the relevant tone. The problem is you have to wait for the tone before dialling the next digit, so it's possible to dial too quickly for the unit to understand and out-pace the tones.

Andy.
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.