> Yes the green LED does light up, although as you or someone mentioned its a little dimmer. Not as bright as the Red. No big deal.
>
> thanks again.
>
I'm glad it works for you, BUT...
It seems to me the transistors 25 Volt rating is a problem during the
90V ring.
I also thought the impedance is way to low and would cause the phone
company to start checking the line for problems.
Anyone disagree with me?
Mikek
Reply by steve●March 4, 20132013-03-04
Yes the green LED does light up, although as you or someone mentioned its a little dimmer. Not as bright as the Red. No big deal.
thanks again.
Reply by Peabody●March 4, 20132013-03-04
steve says...
> In my first post I put up a link to the diagram that I
> was using for this circuit. One of the comments under
> the diagram said that I should use 3.3k Resistor for R2.
> Not the 33k that the diagram indicates. This comment was
> WRONG. As soon as I put back the 33k into R2 things
> worked find.
That's great. And does the green LED still light up at all?
> In my weak defense I have found that diagrams are wrong
> sometimes and I have struggled for days trying to get
> something to work that in the end would never work
> because the diagram was wrong. I was standing on the
> shoulders of the comment of another user and they were
> wrong. How they got it to work with the wrong R value I
> dont know. Unless it was a deliberate mistake.
I don't think it was malicious. The logic was simply that
the right resistor to light up the green LED was 3.3k, just
like the resistor for the red LED. But that's not quite
right because the source voltage for the green LED is 48V,
not the 10V source for the red LED.
Anyway, congratulations on getting it to work.
Reply by steve●March 4, 20132013-03-04
I wanted to get back to the group as I was the original poster of this. It =
has certainly generated some discussion.
Anyway I solved my problem.
In my first post I put up a link to the diagram that I was using for this c=
ircuit. One of the comments under the diagram said that I should use 3.3k R=
esistor for R2. Not the 33k that the diagram indicates. This comment was WR=
ONG. As soon as I put back the 33k into R2 things worked find.
In my weak defense I have found that diagrams are wrong sometimes and I hav=
e struggled for days trying to get something to work that in the end would =
never work because the diagram was wrong. I was standing on the shoulders o=
f the comment of another user and they were wrong. How they got it to work =
with the wrong R value I dont know. Unless it was a deliberate mistake.
Thanks for all your comments they helped me acheive the goal of the finishe=
d project.
Reply by Ian Field●March 3, 20132013-03-03
"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in message
news:inh7j89b3v2e9889e2kgij9dq65o0tnkpd@4ax.com...
> On Sun, 3 Mar 2013 19:07:32 -0000, "Ian Field"
> <gangprobing.alien@ntlworld.com>
> wrote:
>
>>
>>
>>"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in
>>message
>>news:ISMYs.81579$KR.62297@newsfe27.iad...
>>> John Larkin wrote:
>>>
>>>> On Thu, 28 Feb 2013 18:42:53 -0500, Jamie
>>>> <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>>>>
>>>>
>>>>>steve wrote:
>>>>>
>>>>>>I tested and built the following circuit.
>>>>>>
>>>>>>http://www.circuitstoday.com/telephone-in-use-indicator
>>>>>>
>>>>>>It all worked fine untill I tried to test it by calling into my phone.
>>>>>>(the one test I didnt do before I soldered it all together)
>>>>>>
>>>>>>What happens is taht the phone rings for a about 1/2 a ring then stops
>>>>>>ringing.
>>>>>>To my surprise when I life the phone up the line is alive eg. Its like
>>>>>>the device has answered the phone.
>>>>>>
>>>>>>I think that the circuit must be drawing too much power and then
>>>>>>telling
>>>>>>the phone that it has been answered, because the voltage has gone
>>>>>>down.
>>>>>>I have had to replace the Transistors with NTE199, which according to
>>>>>>the book are the same. I have also used a rectifier that is a 2 amp
>>>>>>400v
>>>>>>SIP 2KBP04M-1.
>>>>>>Im wondering if I used a different rectifier if that would change the
>>>>>>results?
>>>>>>
>>>>>>I recognize that your not suppse to take power from the phone co. but
>>>>>>I
>>>>>>would like to get this circuit working. Can anyone tell me why its not
>>>>>>working.
>>>>>>thanks.
>>>>>
>>>>>
>>>>> I think some one gave you some bad transistor numbers..
>>>>>
>>>>> THe phone system in the US rings at around 100 Volts AC and on hook
>>>>> is
>>>>> around 50Volts. Off hook may give you around 10 volts and it depends
>>>>> on
>>>>> how many phones you have at one time off hook.
>>>>>
>>>>> The 2N3392 can only handle 25Volts and it may work if you can insure
>>>>> that the unit will switch on in time to load it down. Further more,
>>>>> the
>>>>> other transistor will be sitting there with this 50v (on hook),
>>>>> leaking
>>>>>through the collector.
>>>>>
>>>>> The NTE199 replacement isn't much better, it has a 70V limit at best
>>>>> and
>>>>> most likely will work find when on hook, but when it rings, you can
>>>>>expect some leaking to be taking place.
>>>>>
>>>>> You first need to get HV transistors.
>>>>>
>>>>> Try getting some 2N5550 transistors, or the 2N5551 which is a little
>>>>>higher..
>>>>> Mouser.com has 2N5551 for 0.78 ech and they have over 3k in stock.
>>>>>
>>>>>
>>>>>Jamie
>>>>
>>>>
>>>> How about a pair of back-to-back paralleled LEDs in series with the
>>>> line?
>>>> Rings
>>>> would be bright, off-hook less bright. Might look cool, especially with
>>>> different color LEDs.
>>>>
>>>>
>>>
>>> Not sure how the audio would sound going through diodes.
>>
>>
>>Like about 1 3/4V of crossover distortion on a 48V signal.
>
> No. The DC line current dominates.
Oops - forgot about that, I was still in on-hook mode.
I put a hand traced schematic of all the discrete transistor circuitry from
a phone, on ABSE over a month ago.
Reply by John Larkin●March 3, 20132013-03-03
On Sun, 3 Mar 2013 19:07:32 -0000, "Ian Field" <gangprobing.alien@ntlworld.com>
wrote:
>
>
>"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in message
>news:ISMYs.81579$KR.62297@newsfe27.iad...
>> John Larkin wrote:
>>
>>> On Thu, 28 Feb 2013 18:42:53 -0500, Jamie
>>> <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>>>
>>>
>>>>steve wrote:
>>>>
>>>>>I tested and built the following circuit.
>>>>>
>>>>>http://www.circuitstoday.com/telephone-in-use-indicator
>>>>>
>>>>>It all worked fine untill I tried to test it by calling into my phone.
>>>>>(the one test I didnt do before I soldered it all together)
>>>>>
>>>>>What happens is taht the phone rings for a about 1/2 a ring then stops
>>>>>ringing.
>>>>>To my surprise when I life the phone up the line is alive eg. Its like
>>>>>the device has answered the phone.
>>>>>
>>>>>I think that the circuit must be drawing too much power and then telling
>>>>>the phone that it has been answered, because the voltage has gone down.
>>>>>I have had to replace the Transistors with NTE199, which according to
>>>>>the book are the same. I have also used a rectifier that is a 2 amp 400v
>>>>>SIP 2KBP04M-1.
>>>>>Im wondering if I used a different rectifier if that would change the
>>>>>results?
>>>>>
>>>>>I recognize that your not suppse to take power from the phone co. but I
>>>>>would like to get this circuit working. Can anyone tell me why its not
>>>>>working.
>>>>>thanks.
>>>>
>>>>
>>>> I think some one gave you some bad transistor numbers..
>>>>
>>>> THe phone system in the US rings at around 100 Volts AC and on hook is
>>>> around 50Volts. Off hook may give you around 10 volts and it depends on
>>>> how many phones you have at one time off hook.
>>>>
>>>> The 2N3392 can only handle 25Volts and it may work if you can insure
>>>> that the unit will switch on in time to load it down. Further more, the
>>>> other transistor will be sitting there with this 50v (on hook), leaking
>>>>through the collector.
>>>>
>>>> The NTE199 replacement isn't much better, it has a 70V limit at best and
>>>> most likely will work find when on hook, but when it rings, you can
>>>>expect some leaking to be taking place.
>>>>
>>>> You first need to get HV transistors.
>>>>
>>>> Try getting some 2N5550 transistors, or the 2N5551 which is a little
>>>>higher..
>>>> Mouser.com has 2N5551 for 0.78 ech and they have over 3k in stock.
>>>>
>>>>
>>>>Jamie
>>>
>>>
>>> How about a pair of back-to-back paralleled LEDs in series with the line?
>>> Rings
>>> would be bright, off-hook less bright. Might look cool, especially with
>>> different color LEDs.
>>>
>>>
>>
>> Not sure how the audio would sound going through diodes.
>
>
>Like about 1 3/4V of crossover distortion on a 48V signal.
No. The DC line current dominates.
--
John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators
Reply by John Larkin●March 3, 20132013-03-03
On Sun, 03 Mar 2013 13:55:47 -0500, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>John Larkin wrote:
>
>> On Thu, 28 Feb 2013 18:42:53 -0500, Jamie
>> <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>>
>>
>>>steve wrote:
>>>
>>>>I tested and built the following circuit.
>>>>
>>>>http://www.circuitstoday.com/telephone-in-use-indicator
>>>>
>>>>It all worked fine untill I tried to test it by calling into my phone.
>>>>(the one test I didnt do before I soldered it all together)
>>>>
>>>>What happens is taht the phone rings for a about 1/2 a ring then stops ringing.
>>>>To my surprise when I life the phone up the line is alive eg. Its like the device has answered the phone.
>>>>
>>>>I think that the circuit must be drawing too much power and then telling the phone that it has been answered, because the voltage has gone down.
>>>>
>>>>I have had to replace the Transistors with NTE199, which according to the book are the same. I have also used a rectifier that is a 2 amp 400v SIP 2KBP04M-1.
>>>>Im wondering if I used a different rectifier if that would change the results?
>>>>
>>>>I recognize that your not suppse to take power from the phone co. but I would like to get this circuit working. Can anyone tell me why its not working.
>>>>thanks.
>>>
>>>
>>> I think some one gave you some bad transistor numbers..
>>>
>>> THe phone system in the US rings at around 100 Volts AC and on hook
>>>is around 50Volts. Off hook may give you around 10 volts and it depends
>>>on how many phones you have at one time off hook.
>>>
>>> The 2N3392 can only handle 25Volts and it may work if you can insure
>>>that the unit will switch on in time to load it down. Further more, the
>>>other transistor will be sitting there with this 50v (on hook), leaking
>>>through the collector.
>>>
>>> The NTE199 replacement isn't much better, it has a 70V limit at best
>>>and most likely will work find when on hook, but when it rings, you can
>>>expect some leaking to be taking place.
>>>
>>> You first need to get HV transistors.
>>>
>>> Try getting some 2N5550 transistors, or the 2N5551 which is a little
>>>higher..
>>> Mouser.com has 2N5551 for 0.78 ech and they have over 3k in stock.
>>>
>>>
>>>Jamie
>>
>>
>> How about a pair of back-to-back paralleled LEDs in series with the line? Rings
>> would be bright, off-hook less bright. Might look cool, especially with
>> different color LEDs.
>>
>>
>
> Not sure how the audio would sound going through diodes.
>
>Jamie
No problem. One of the diodes would be forward biased by the DC line current, so
would have a dynamic impedance of a couple of ohms and no significant
distortion.
--
John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators
Reply by Ian Field●March 3, 20132013-03-03
"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in message
news:ISMYs.81579$KR.62297@newsfe27.iad...
> John Larkin wrote:
>
>> On Thu, 28 Feb 2013 18:42:53 -0500, Jamie
>> <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>>
>>
>>>steve wrote:
>>>
>>>>I tested and built the following circuit.
>>>>
>>>>http://www.circuitstoday.com/telephone-in-use-indicator
>>>>
>>>>It all worked fine untill I tried to test it by calling into my phone.
>>>>(the one test I didnt do before I soldered it all together)
>>>>
>>>>What happens is taht the phone rings for a about 1/2 a ring then stops
>>>>ringing.
>>>>To my surprise when I life the phone up the line is alive eg. Its like
>>>>the device has answered the phone.
>>>>
>>>>I think that the circuit must be drawing too much power and then telling
>>>>the phone that it has been answered, because the voltage has gone down.
>>>>I have had to replace the Transistors with NTE199, which according to
>>>>the book are the same. I have also used a rectifier that is a 2 amp 400v
>>>>SIP 2KBP04M-1.
>>>>Im wondering if I used a different rectifier if that would change the
>>>>results?
>>>>
>>>>I recognize that your not suppse to take power from the phone co. but I
>>>>would like to get this circuit working. Can anyone tell me why its not
>>>>working.
>>>>thanks.
>>>
>>>
>>> I think some one gave you some bad transistor numbers..
>>>
>>> THe phone system in the US rings at around 100 Volts AC and on hook is
>>> around 50Volts. Off hook may give you around 10 volts and it depends on
>>> how many phones you have at one time off hook.
>>>
>>> The 2N3392 can only handle 25Volts and it may work if you can insure
>>> that the unit will switch on in time to load it down. Further more, the
>>> other transistor will be sitting there with this 50v (on hook), leaking
>>>through the collector.
>>>
>>> The NTE199 replacement isn't much better, it has a 70V limit at best and
>>> most likely will work find when on hook, but when it rings, you can
>>>expect some leaking to be taking place.
>>>
>>> You first need to get HV transistors.
>>>
>>> Try getting some 2N5550 transistors, or the 2N5551 which is a little
>>>higher..
>>> Mouser.com has 2N5551 for 0.78 ech and they have over 3k in stock.
>>>
>>>
>>>Jamie
>>
>>
>> How about a pair of back-to-back paralleled LEDs in series with the line?
>> Rings
>> would be bright, off-hook less bright. Might look cool, especially with
>> different color LEDs.
>>
>>
>
> Not sure how the audio would sound going through diodes.
Like about 1 3/4V of crossover distortion on a 48V signal.
Reply by Jamie●March 3, 20132013-03-03
John Larkin wrote:
> On Thu, 28 Feb 2013 18:42:53 -0500, Jamie
> <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>
>
>>steve wrote:
>>
>>>I tested and built the following circuit.
>>>
>>>http://www.circuitstoday.com/telephone-in-use-indicator
>>>
>>>It all worked fine untill I tried to test it by calling into my phone.
>>>(the one test I didnt do before I soldered it all together)
>>>
>>>What happens is taht the phone rings for a about 1/2 a ring then stops ringing.
>>>To my surprise when I life the phone up the line is alive eg. Its like the device has answered the phone.
>>>
>>>I think that the circuit must be drawing too much power and then telling the phone that it has been answered, because the voltage has gone down.
>>>
>>>I have had to replace the Transistors with NTE199, which according to the book are the same. I have also used a rectifier that is a 2 amp 400v SIP 2KBP04M-1.
>>>Im wondering if I used a different rectifier if that would change the results?
>>>
>>>I recognize that your not suppse to take power from the phone co. but I would like to get this circuit working. Can anyone tell me why its not working.
>>>thanks.
>>
>>
>> I think some one gave you some bad transistor numbers..
>>
>> THe phone system in the US rings at around 100 Volts AC and on hook
>>is around 50Volts. Off hook may give you around 10 volts and it depends
>>on how many phones you have at one time off hook.
>>
>> The 2N3392 can only handle 25Volts and it may work if you can insure
>>that the unit will switch on in time to load it down. Further more, the
>>other transistor will be sitting there with this 50v (on hook), leaking
>>through the collector.
>>
>> The NTE199 replacement isn't much better, it has a 70V limit at best
>>and most likely will work find when on hook, but when it rings, you can
>>expect some leaking to be taking place.
>>
>> You first need to get HV transistors.
>>
>> Try getting some 2N5550 transistors, or the 2N5551 which is a little
>>higher..
>> Mouser.com has 2N5551 for 0.78 ech and they have over 3k in stock.
>>
>>
>>Jamie
>
>
> How about a pair of back-to-back paralleled LEDs in series with the line? Rings
> would be bright, off-hook less bright. Might look cool, especially with
> different color LEDs.
>
>
Not sure how the audio would sound going through diodes.
Jamie
Reply by Ian Field●March 3, 20132013-03-03
"Jon Kirwan" <jonk@infinitefactors.org> wrote in message
news:7l37j89pon3c6c35lbhgds841uta9eb4fs@4ax.com...
> On Sun, 3 Mar 2013 16:30:33 -0000, "Ian Field"
> <gangprobing.alien@ntlworld.com> wrote:
>
>>
>>
>>"Jon Kirwan" <jonk@infinitefactors.org> wrote in message
>>news:3g65j8p5fcrfcn03jtqf57rr1ain4e04tn@4ax.com...
>>> On Sat, 2 Mar 2013 21:22:37 -0000, "Ian Field"
>>> <gangprobing.alien@ntlworld.com> wrote:
>>>
>>>>
>>>>
>>>>"Jon Kirwan" <jonk@infinitefactors.org> wrote in message
>>>>news:7sm4j81hs4ep7gti49mukuolcvv68unerc@4ax.com...
>>>>> On Thu, 28 Feb 2013 11:22:00 -0800 (PST), steve
>>>>> <stevesemple@lycos.com> wrote:
>>>>>
>>>>>>I tested and built the following circuit.
>>>>>>
>>>>>>http://www.circuitstoday.com/telephone-in-use-indicator
>>>>>>
>>>>>> It all worked fine untill I tried to test it by calling into
>>>>>> my phone. (the one test I didnt do before I soldered it all
>>>>>> together)
>>>>>>
>>>>>> What happens is taht the phone rings for a about 1/2 a ring
>>>>>> then stops ringing. To my surprise when I life the phone up
>>>>>> the line is alive eg. Its like the device has answered the
>>>>>> phone.
>>>>>>
>>>>>> I think that the circuit must be drawing too much power and
>>>>>> then telling the phone that it has been answered, because
>>>>>> the voltage has gone down.
>>>>>>
>>>>>> I have had to replace the Transistors with NTE199, which
>>>>>> according to the book are the same. I have also used a
>>>>>> rectifier that is a 2 amp 400v SIP 2KBP04M-1.
>>>>>>
>>>>>> Im wondering if I used a different rectifier if that would
>>>>>> change the results?
>>>>>>
>>>>>> I recognize that your not suppse to take power from the
>>>>>> phone co. but I would like to get this circuit working. Can
>>>>>> anyone tell me why its not working.
>>>>>>
>>>>>>thanks.
>>>>>
>>>>> There is quite a long specification for telephone lines in
>>>>> the US. I have a copy, thanks to Don Bowey, when he dropped a
>>>>> copy over at my home back around 2003 or so. It represents an
>>>>> industry composite of various systems and includes envelopes
>>>>> of operation. The gist of it is, as Don wrote before coming
>>>>> over back then,
>>>>>
>>>>> "The FCC R&R require a minimum of 5M of customer premises
>>>>> equipment loop resistance in the on-hook state. Also.
>>>>> at 220uA some Central Offices will declare a line fault
>>>>> and remove the line from service."
>>>>>
>>>>> The basic idea of presenting 5MOhm total customer premises
>>>>> load (that is the TOTAL of all phones and connected
>>>>> equipment) when on-hook is incredibly hard to meet with an
>>>>> unpowered attachment that shows "in use" and "not in use" led
>>>>> lights.
>>>>>
>>>>> I've also read that, "if you are in USA or canada Bellcore
>>>>> specs allow a max of 5micro amps at 48VDC in an on-hook
>>>>> state." That's 10MOhm, in effect, though I believe the 5MOhm
>>>>> for the entire premises still fits the spec.
>>>>>
>>>>> The upshot here is that you aren't going to be seeing an LED
>>>>> lit continuously and still meet on-hook specifications. You
>>>>> can design a system to blink periodically,
>>>>
>>>>If you can use that 48V to charge a capacitor above 32V without
>>>>violating
>>>>the on hook current spec; you can make an LED flash very brightly
>>>>periodically by dumping the cap into it with a DB3 diac.
>>>>
>>>>You'd have to trial & error for how many uF to make the flash bright
>>>>enough
>>>>without blowing the LED.
>>>
>>> Yeah, that is true enough I suppose. So examine:
>>>
>>> http://www.infinitefactors.org/misc/spice/Pulser%202.png
>>
>>Seems rather elaborate when 1 resistor, 1 capacitor, 1 diac & 1 LED would
>>do
>>the same job just as well.
>
> It's a reliable design, as I've built a couple, at least.
>
> I've not used diacs, yet. Just a hobbyist. But yes, I can see
> how that should work. Breakover voltage is higher, which has
> its advantages in this application.
>
> Any particular diac you'd consider trying?
I already suggested the DB3 in the post I sent yesterday.
They're fairly common in UK CFLs, although Philips don't use them in types
less than 18W.