Sometimes it happens that the home radiotelephone becomes obsolete and ceases to please: there are new models with which you want to āchangeā to please yourself and your loved ones.
Sometimes it also happens that it befalls local failure: for example, my phone Texet TX-D5300 after falling on the floor has ceased to display on the screen some characters, and reading information has turned to my torture.Disassembled the tool and improved the contact between the display and the circuit board and got nothing.
Author: Andrew Kashkarov, Saint-Petersburg
Tank author Andrei Kashkarov: and youāre doing redesigns?
Then weāre coming to you!
Donāt part with your loved ones or a new life for old things
There are, unfortunately, hundreds and thousands of cases like this. Small up to 1000 Dollars the cost of such devices suggests that the owner without regret will replace such a phone, as cost-effectiveness of the repair outweighs the cost of the product itself.
Nevertheless, such ālame ducksā ā radiotelephones with minor defects, are quite suitable for the hands of a radio amateur to breathe new life into them.For example, itās not hard to turn a ātoyā into a remote door opener.
You can go even further and teach the ālame duckā to alert by sound about any other change of controlled space within the apartment or office. The important thing is that the transmit and receive paths are working, and that the āhandset searchā function works. Next, I will tell you how to make a useful thing out of such a half-defective wireless kit.
Result of rework: looking for a tube, found an open door
In Fig. 1 shown is the appearance of the Texet TX-D5300 wireless kit: base and one handset.
To improve the original set base + handset you will need to make a few simple steps. Here they are:
- Disassemble the base of the radiotelephone remove the case to access the circuit board
- Connect a two-wire loop with a maximum length of 1.5 m in parallel to the contacts of the āhandset searchā button to avoid false responses from AC voltage crosstalk from the mains wires
- Connect the other end of the line to the limit switch normally closed or the reed switch with normally closed contacts on the front door frame see Pic. details below
- Set fix the base of the radiotelephone here, not far from the āremote switch
- with the help of standard adapter connect the base to 220 V
- to connect the remote handset to another additional power adapter with 3-5V output voltage, so as not to depend on discharged batteries or accumulators in the handset
- place the handset with the adapter in the right place, for example, not far from the desk.
Letās take a closer look at these steps.
In Fig. 2 shown is the base view with the housing cover removed.
In the center of the circuit board fig. 2 There is a button with contacts to close it has 4 leads, two of which are connected duplicate each other . Use ohmmeter to check the connection in the contact group of the button ā when you click on it we identify the closing contacts.
We solder them in parallel with a soldering iron with a thin sting and power up to 25 W not to damage radio elements on the printed-circuit board solder a double-core flat strip, thereās no need to screen it Fig. 3 .
The connection scheme is simple enough, and in my opinion, does not even need to publish a separate figure. This is a reed switch connected in parallel with the button on the base āhandset search.
Next, it is necessary to explain the principle of the Texet TX-D5300 radiotelephone in the handset search mode.
The base has nothing to do with it: a trill will sound for 3 seconds
when pressing the button āhandset searchā in the central part of the base ā if the base is connected to 220 V and the batteries are charged directly in the handset ā the latter emits a short trill of 2.5 ā¦ 3 sec. Moreover, this occurs regardless of whether the base is connected to a telephone line, which made it possible to use the old radiotelephone not for its intended purpose.
If you press the āhandset searchā button for a long time or repeatedly with a frequency of more than 1 time in 5 seconds the sound signal will still be only a single, lasting a few seconds. The same will happen when you open the door, which has a ācontact closure. This is a feature of the industrial design phone Texet TX-D5300.
In Fig. Figure 4 shows the reed switch, aligned with the magnet on the moving part of the door.
With the door firmly closed Fig. 4 the magnet acts with its field on the reed switch and the contacts of the latter are opened. When you open the door, the reed switch is in normal mode with the contacts closed. This condition is transmitted to the base and the phone makes a hysterical beep. As a reed switch I use KEM-3-1 with three contacts.
To power the handset radiotelephone located within 30 meters of the base, I use an adapter for powering Nokia cell phone with an output constant voltage of 3.7 ā¦ 4.2 v. In this case, any unnecessary charger with an output voltage in the specified range will do.
Fig. 5. Radio handset and new power adapter
Technical characteristics of the base unit TX-D5300 firm Texet
- DECT GAP standard possibility of registering additional handsets from other manufacturers
- menu in American
- Phone book of 50 names and numbers redial the last 10 dialed numbers
- Caller ID AON/Caller ID with memory of 40 numbers
- Possibility to connect up to 5 handsets wireless PBX : internal connection between handsets
- Operating frequency: 1880-1900 MHz
- Texet TX-D5300 wireless indoor outdoor range up to: 50m/300m
- number identifier only in the model Texet TX-D5300 Black
- Interfaces: Texet TX-D5300 Black RJ-11 input.
Security and service features in the Texet TX-D5300 Black:
- turn off the microphone
- keypad lock
- time indication
- battery discharge indication
- indication of the exit beyond the communication zone of the base unit
- handset search.
The base is powered by a 6.5V DC adapter 150mA current consumption .
The phone is powered by two AA-size AA batteries, 1.2 V and a power capacity of 550 mA/h each.
Breaking news: the toilet is already freeā¦
As I noted, the options for using the revised device can be many: if only there was something to signal.
For example, in addition to the proposed alarm about the opening of the front door, in a different location sensor can joyfully inform you if the toilet or bathroom is not occupied, if there is not a leak somewhere, if the fan or air conditioner is not on in another room. And then there are the loggias, which sometimes open, too ā and thereās not much else weād like to get the latest news?
To implement any of these ideas, you just need to take care of placing the contact sensor directly in the area of its triggering and place a radiotelephone base nearby.
Instead of the contacts of the reed switch button or a switch to close you can even use an electronic circuit with control based on electronic switches chips K190KT1 ā K190KT2, multiplexers or relays . But this is another story, more complicated.
An interesting idea: our development can also be used for the protection of real estate. It will require one handset and one neighbor. If you install the tube at a neighbor in the stairwell subject to prior consensus with her , then during your long absence, this same neighbor, not indifferent to other peopleās secrets, will always know that you have āsomeone opened the doorā, and will be able, hopefully, in time to call āthe rightā.
So, take advantage and prosper!
What is the reason behind tankers not leaving their exes behind and giving a new life to the radio phone? Is there any particular significance or advantage for them in doing so?