Simple Phone Tap

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Derek Tombrello 385,012 2 98
This circuit is extremely simple, therefore there is less chance of any problems. It can be placed anywhere on the phone line and it will record any conversation on any phone on that line.

Please note: I have received several emails saying that this circuit will not work and that it may hold your line off hook and to me it looks like it will (it would put quite a load on the phone line). For some, it has worked fine. Build at your own risk.


This the Schematic of the Simple Phone Tap


Total Qty.
R11470 Ohm 1/4 Watt Resistor
R211K 1/4 Watt Resistor
R31100K 1/4 Watt Resistor
R416K 1/4 Watt Resistor
C1, C220.01 uF 100V Ceramic Capacitor
K1124VDC Reed Relay
MISC1Wire, Headphone Plugs, Phone Plug Or Alligator Clips


  1. Email Derek Tombrello with comments, questions, etc.
  2. To use the circuit, simply connect it in series to the phone. Then plug in the recorder. It will start recording when the phone is picked up.
  3. The values of R1 and R2 may have to be adjusted, depending on the characteristics of the phone line it is connected to (they vary). If the R1+R2 combination is increased sufficiently (try 2.47K) then the circuit can be connected in parallel with the line, thus covering all attached devices. (Thanks to Mark Wright for the suggestion).
  4. T.A. Betts offers this suggestion for getting this problematic circuit working: "If you drop the resistors and add a 2.2uF capacitor the line will not stay off hook. It blocks the DC from the moniter position."

Related Circuits

Ringing Phone Light Flasher, Phone Busy Indicator, FM Telephone Bug, Cut Phone Line Detector, Simple Phone Tap, Telephone Hold Button, Telephone Recorder, Remote Telephone Ringer


Add A Comment

Simple Phone Tap
Tuesday, February 28, 2012 2:13:13 PM
First of all it is illegal to tap,listen or record someones phone conversation. if you are going to do it anyway go to another site and find out how because the editor is a jerk on this page. All you women really need to leave those men you are with because it only gets worst.
Simple Phone Tap
Tuesday, February 07, 2012 1:08:08 AM
I want to find just ONE clue that my boyfriend is cheating, but I dont want to pay LOTS Please can someone help?

(Editor's notes: Ask him? Maybe you're the one cheating. After all, statistics say that 50% of men cheat, while 60% of women cheat.)

Simple Phone Tap
Monday, March 21, 2011 4:14:35 AM
Could the relay be used open/close the line going directly to the audio jack thereby muting/opening the audio line to the recording device? My recorder has no remote input, but does record when sound is heard.
very upset
Simple Phone Tap
Saturday, December 18, 2010 4:31:17 AM
My boyfriend is very possesive and i noticed in his history that he is inquiring about you product. Please tell me what he will be doing to get into my personal cell phone and what i can do to prosecute him. This is a total invasion of privacy. TELL ME, how is he doing this and how do i stop it... Has he put a chip in his cell phone or mine? Is he tapping my home phone as well. This is unbelievable and i want to know how to put a stop to his snooping. Not all women are cheaters, but most men are paranoid cuz they're in fact the cheaters. Please tell me where to find this chip in his phone so i can stop this before it gets bad.

(Editor's notes: Dump him. Problem solved.)

Simple Phone Tap
Wednesday, December 08, 2010 4:41:57 PM
Before 1986, the cordless phones used two frequencies, 49.860 MHz and 1.6 MHz, just above the AM broadcast band. The handset transmitted on 49.86, and the base unit transmitted on 1.6 MHz. The walkie talkies then were also on 49.86 MHz, so you could hear the telephone handsets in the neighborhood with a walkie talkie. In 1986, the new federal law prohibited monitoring this, and the manufacturers stopped using those frequencies. The frequencies cordless telephone were moved to much higher bands. The walkie talkies were also moved, to the family radio service, I believe. In any case, the 49.86 MHz band was no longer used. Now, instead of your children monitoring you, you're probably being monitored by Big Brother. :-(
Simple Phone Tap
Monday, November 22, 2010 11:25:30 PM
Back when I was a little kid (5 or 6) I recall messing with a walkie talkie once when I was bored. I started TRYING to spell my name in morse code. The next thing I knew I could through the WT my mother, who was upstairs, talking on the phone to a friend. It was only 1-way, I tried talking to her through it. Then I ran upstairs and told her exactly what she said and had her talk into the phone and hear the WT. What was this code? Do any of you know what thats all about? It was just a kid's toy walkie talkie...

(Editor's notes: Many cordless phones and walkie talkies share the same frequency range. They interfered with each other.)

Simple Phone Tap
Saturday, September 19, 2009 10:50:49 AM
How can I detect a phone tap on my line from the outside pole? What should I look for and listen for?
Melissa Green
phone tap
Friday, September 18, 2009 11:17:40 AM
My house phone is tap. What do i do to untapped my phone

(Editor's notes: No, it's not.)

miss dumber
Simple Phone Tap
Wednesday, September 16, 2009 1:49:34 PM
Hi I think i'm pregnant and the father has been playing around, can a simple fone tap cure my pregnacy ?
Simple Phone Tap
Thursday, September 10, 2009 10:01:46 PM
If you honestly have that bad of trust issues you need to tap your significant other's phone, you should post on other forums like montel williams and jerry springer. They are profesionals in that technical area
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