how entering sleep mode

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

Okay folks,
thanks for your attention en info.

Yes indeed, a flipflop for each relais will do the job, i think.
Bistable relais will be simpler, but i do not know if there are bistable relais for high power.
Because this tuner setup is just a test to get used to the problems .
When this test is okay, i will build a tuner for about 4 KWatt.
My licence has a max of 400 Watt, but with some antenna's the voltage or current will be
terribly high. My goal is to be able to use every kind of antenna without any problems.

In Ham radio, this kind of tuners are not available. Militairy ships does have them, but
they are above my budget.....

So first i will try to find a solution for the noise problem.

for general info: the receiver has its own power supply and stands 5 meter away of the AVR.
The AVR and the relais has one 24 Volt power supply. from which i made also the 5 Volt for
the AVR itself.

Well, today an other day of testing.

I am very greatfull for your help!!!

73
Wim PA0SLT

SZTRAD · Joined: 30 Dec 2019 Posts: 165

You need to draw by hand how to control those relays. Feel free to involve one output so that we are in the picture

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

SZTRAD,
My bascom program works very nice... the problem is only the noise when i go receiving

MWS · Joined: 22 Aug 2009 Posts: 2262

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

Hi MWA,
i do use 24 relais, but in de definitive version it will be some more.

I think your info will be too much, too complicated. It must be possible
to do this simple....

the flipflop methode will be reasonable simple.
than comes the next question: with which command can i completely
shut down the AVR.... So that i have to start it again with first
power off and than switch power on again.?
Point is , this tuning unit comes 150 m. from my house.
When it works nice, i will never touch it again..... hi hi

there is an other possible noice source.. the transisitors that go to the
relais... ( because the AVR can nog deliver anough current for the relais)
I will look for this to day.

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

oh oh i have a terrible problem:
If i disconnect the power for the AVR and the display.
and i give 24 volt to a relais.....i get noise....
Not with every relais.. but some relais.

So the noise does not come from the AVR but from something else.....

this is unbelievable.

so first i have to find what is happening...

i will keep you informed here...

Wim

SZTRAD · Joined: 30 Dec 2019 Posts: 165

That's why I wanted to see the performance part involved.
I did not ask about the program but about the method of connection. Relays with high coil resistance are quite often a source of large interference.

MWS · Joined: 22 Aug 2009 Posts: 2262

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

SZTRAD,
what do you mean by a "performance chart"?

Paulvk · Joined: 28 Jul 2006 Posts: 1257 Location: SYDNEY

Noisy relays !
Have you put diodes across the coils ?
Have you also put 100nF capacitors across the coils.
Relay contacts can be a source of noise.

Can you publish your project for others there is is project section in the forum.

Regards Paul vk2pl

MWS · Joined: 22 Aug 2009 Posts: 2262

SZTRAD · Joined: 30 Dec 2019 Posts: 165

If I understood correctly you will switch great powers. They redraw the connection of the relay and imagine it as a transformer. The contacts have their internal resistance so you will have one winding the relay coil is the other winding. You have to compensate for what is induced in your winding. If you transmit power to the antenna, a relatively oscillating current through the contact will return to you. Well, you have such a small switching power supply.
These effects must be blocked. It is necessary to put a blocking diode for the coil, as MWS writes (it is there due to the opening and the peak of the opposite voltage arising when the coil is disconnected from the power supply). It is necessary to strictly block the power supply and switching transistors for each coil.
It is bad advice when one does not see the wiring diagram and that is what needs to be seen. In the case of switching large powers for HF technology, you also need to see the PCB, etc. Sorry if I touch you now, but here you need to forget about universal diagrams from Arduino and other simple projects.
RS

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

Hi, MWS, Paulvk, O-Family, SZTRAD,

i found the noise problem. It did not come from the avr and the tuner.
Now i do know it, it looks very stupid.
Between the small wire antenna and the line to the receiver is large coil. The relais switch some points of this coil short-circuited. So it grows larger or smaller.
When no relais is on, the coil is maximal. That blocks the noise from the antenna to the receiver.
When i activate a relais, this coil is much smaller, so the noise from the antenna can go to the receiver.
So when the automatic tuning process stops, there is always one relais activated, so the coil is smaller .
So i do receive noise.
When i put the avr in programming mode, all relais switch off... so the coil is maximum.
So there come no noise to the receiver....
I found this by switching all electronics off and took a wire to do the the same what a relais does...
and without wire connection there was no noise, and with the wire there comes the noise.
So the noise did not come from the electronics,,, but from the antenna.
This small antenna is in my radio-room. In this room are led-TL-lamps.... this lamps gives a lot of noise....

I hope i explained it right... sorry my English is very bad.

Anyhow, i do know now how to switch the AVR off and what are the consequences of that.

Now i will go on with all other problems of this antenna tuner, like ( as you mentioned) large current,
largs voltages, big relais, switching times and an effecient bascom program.
Hopefully there will not come smoke out of this tuner in the future.
Because you know: electronics is made of smoke.. When the smoke is out of the apparatus, the apparatus
is dead.

Thank you all for your help and suggestions.
i am very greatfull.
(if you like to see what kind of experiments i like to do... see my site: www.ebl21.nl )

Wim PA0SLT

SZTRAD · Joined: 30 Dec 2019 Posts: 165

Hmm, only locals will probably read this. Google translator broke his teeth Smile

Don't make any of it Czech language is the same.

wimapon · Joined: 26 Oct 2008 Posts: 24 Location: Meedhuizen

i am sorry,... the radio astronomy item is in english