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ashveen
New Member
1 Posts |
 Posted - Mar 17 2009 : 06:48:27 AM
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hi, im trying to assemble the cct Ringing Phone Light Flasher
(http://www.aaroncake.net/circuits/pflash.asp) , but i need to modify the cct so as to activate a magnetic door latch,
if there any configuration i need to know to be able to do this?
also, im unable to get the 2N27 opto isolator, instead the 2N26 is available. will that cause a problem in the cct.
for the C1 0.47uF 250V, 0.47uF 50V is available.
will the cct work if i use the components available to me?
looking forward for some help
thanks!!
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audioguru
Nobel Prize Winner
Canada
4218 Posts |
Posted - Mar 17 2009 : 11:48:50 AM
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quote:
Originally posted by ashveen
hi, im trying to assemble the cct Ringing Phone Light Flasher
(http://www.aaroncake.net/circuits/pflash.asp) , but i need to modify the cct so as to activate a magnetic door latch,
if there any configuration i need to know to be able to do this?
The circuit is missing an important diode across the relay's coil that stops the transistor from being destroyed by the very high flyback voltage.
Select a relay that the transistor can drive and with contacts rated for the current of the door latch.
quote:
im unable to get the 2N27 opto isolator, instead the 2N26 is available. will that cause a problem in the cct.
The 4N26 is twice as sensitive as the 4N27 so it will work fine.
quote:
for the C1 0.47uF 250V, 0.47uF 50V is available.
The ringing in my country is 90VAC with 48VDC. Its peak voltage is 175V. Your 50V capacitor will be destroyed. |
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telephone ringer with relay
