Entrotec ED4 handset

[SKhlane]

I have this Entrotec ED4 handset unit and i don't hear ring here. What could be the problem? Theres nothing wrong with wiring. Is this common, did anyone had

this problem?

It has 12C508A CMOS microcontroller, ZSR300 semiconductor, ZM331643 supply voltage monitor chips. Any of the chips or capacitors fail give this problem? Or is there a way to test ring in its speakers with short curcuiting some wires there.

 

[sparkymarka]

Things to check , does the privacy switch turn the led ? If not possible blown fuse in controller ,
As its tone generated is the speaker ok in the handset ? Check with multimeter
Is the button on the panel faulty ? Again check with multimeter

 

[SKhlane]

Privacy button which has red, led turns on when i press it and there green led works too for when someone opens the main door. So i guess voltage does come to the unit, we can eliminate blown fuse. There are 4 cables going to speaker & mic inside the handle. There is nothing else inside the handle.

You mentioned the button for the handle is it supposed to give a tone or something when i pick the handle up? I hear absolutley nothing out of the handset. When i short circuit privacy button red led lights on. Nothing when i short circuit handle push button or door open push button. I guess voltage only comes these buttons when someone dials my door number from the main intercome unit or opens the door for the green led. I can hear my neighbours handset ringing but not mine.

This is back of the unit, it shows location of push buttons.

 

[Handymanjo]

Does your neighbours ours handset work correctly speech both ways?
If so you could try and swap handset via RJ11 connector ,that will prove if microphone and speaker in handset?

 

[sparkymarka]

Sorry forgot do you get a ring sound from the downstairs panel when you press the button ? ( the handset must be back in its cradle for this to work )

 

[SKhlane]

Yes, I can hear the ring from the main intercom unit. When short circuiting 0V and DS green LED turns on, just wanted to identify pins.

DS – Door Status
DR – Door Release
VT – DC in 12V
BZ – Buzz input
S2 - Mic
S1 - Speaker
0V – Ground

The cables for the handle; black and yellow are ground as you can see, pink goes to speaker and white for mic. No resistance across speaker but there is for mic, it’s 1.282kΩ So I’m guessing speaker is faulty. Voltage across VT to 0V is 11.12V. There are also various voltages across VT and other pins. And pink cable has a voltage on it too about 0.25V. It says 32Ω 0.25W on the speaker

 

[sparkymarka]

may have a spare speaker if you are stuck ...pm me