Kenwood KR 4200 Relay issue

Its easy to identify them. Just make a not of the colours for these:

1/ The wire that goes to the plus speaker terminal of the left channel sockets.

2/ The wire that goes to the right plus speaker socket.

3/ The wire that goes to the left channel amp.

4/ The wire that goes to the right channel amp.

The coil you know but make sure you keep the diode polarity correct across the existing wires.

For the new relay you connect either middle pin on on one side of the group of three to the the left amp output. You connect the right amp output to the other middle pin of the other sides group of three.

You measure on ohms on your meter from the middle pin to the end pins on one side of the group of three. One of those pins will read with continuity to the middle pin. That is the pin NOT to use. You connect the speaker feeds to the other set of pins.
 
Its easy to identify them.
Thanks!!!
Were getting there!
foto013.jpg
 
I replaced a relay in this model recently. I used a LY2F-DC24. I drilled new holes and mounted it to the back of the chassis where the old one was.
I was doing a full overhaul and I always replace the relay when doing this, if at all possible.
 

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Hello, the relay has arrived...

Finder 40.52.7.024.0000 Relais 24V DC 2xUM 8A 1150R 250V AC Relay Print 069239​

I measured the pins and found the upper two without reading... continuity...
But the problem is now, that after the click and 1/2 sec. it goes back to the beginning state position......
Please, what does that mean?
Christoph
 
But the problem is now, that after the click and 1/2 sec. it goes back to the beginning state position......
Not quite sure what you mean by that tbh 🙂

Do you mean the relay drops out?

Changing the relay has changed your problem and so either the relay isn't configured correctly or is unsuitable in some way. First thing to do is measure the voltage across the coil (that diode) and see what the voltage is (does it match the relay coil voltage) and whether the voltage is constant or whether it cycles on and off.
 
22 volts sounds good as does the click.

My best guess is that you have wired the switch contacts incorrectly and that they are either shorting the outputs to ground when the relay fires or they are shorting one channel to the other. Either scenario would likely trip the over current protection and trip the relay.
 
Okay... This on my side isnt going anywhere... I guess alot of people are fiering , and saying somebody stop him before he wont be able to write anymore... Im done...
I think the KR4200 has some kind of problem I dont undestand... I can solder, but my understanding electronic stuff is very very basic...
Thanks Mooly for your confidence in me... 🙂
I will wait for the day when I meet somebody in town who knows rocket science... 🙂
All the best to all the people reading the thread and their ideas!
There is a german saying that brings this to a point: Schuster, bleib bei Deinen Leisten...
A few days ago I got a KA 601... in better shape 🙂
Christoph
 
Well 🙂

Try putting the old relay back and see if you get back to where it was before. If it does work again then it must be the new relay that is incorrectly configured.

Or... if you can unsolder neatly then just remove solder from the all the switch contact pins. Leave the coil connections connected and see if the relay clicks and stays correctly pulled in. Again, if it does pull in correctly then its just a simple case of incorrect configuration.

No rush... put it away for a few days and then come back to it.

🙂
 
What a great guy... doesnt want to give up... 🙂 Thanks!
So, with only the new relay coil connected it pulls in but 1/2 sec later snaps back...
So, I did check the diode direction... the white ring goes towards left side and to tag 8 of the power supply...
The other side to 17 of the main amp board...
Is it maybe our 236V from the socket? The receiver really wants 215V from the 70es and 80es...
Next week I will have a variac to arrange 215V...
 
And I have 25VDC across the old relay coil... and also after the click...
The new one now has 24VDC after the click but goes back and forth... click.. clock..........click..clock..........click... clock... it doesnt stay...
 
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What a great guy... doesnt want to give up... 🙂 Thanks!

Oh we haven't even started yet 😉

The old one and coil connection only stays pulled in... strange...

Maybe not so strange...

It really does sound like the contacts of the new relay might be in a different configuration to the old and that when the relay closes it is either shorting the amplifier channels to ground or shorting them one to the other.
 
It should look something like this. Identify the two wires that go to the left and right amplifier circuits. Those wires go to the centre pins of the relay.

The two wires that go to the speaker switches connect to the outer pins. If you happen to mix up the connections red/blue or green/brown then all that happens is you would get the left and right channels the wrong way around... easily fixed, just swap one pair of either group around.

Screenshot 2023-03-30 182230.png
 
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